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Sample records for high rate discharge

  1. High-repetition rate UV lasers with inductive-capacitive discharge stabilization

    Science.gov (United States)

    Andramanov, A. V.; Kabaev, S. A.; Lazhintsev, B. V.; Nor-Arevyan, V. A.; Pisetskaya, A. V.; Selemir, V. D.

    2007-04-01

    The high repetition rate UV lasers (XeF [1], KrF [2] and N II) with a new electrode unit are investigated. A multisectional discharge gap 25 cm length and 1.2 cm height is formed by 25 pairs of anode-cathode plates. The discharge width is ~ 1 mm. The average specific pump power is ~ 9 MW cm -3. The main aim of the work is the achievement of a maximum pulse repetition rate (f m) with high output energy stability. At a rather low gas flow velociity <= 19 m s -1 the frequencies f as high as 4 kHz in the excimer lasers and 4.5 kHz in a nitrogen laser are realized. The relative rms deviations of the output energy (σ) for XeF and KrF lasers is in the range 1-2% for f <= 3 kHz and 3-4% for f = 4 kHz. For the nitrogen laser σ <= 1.3% is at f <= 4.5 κΓ\\tscy.The average output power 10 (12) W for the XeF (KrF) laser and 1.1 W for the nitrogen laser are reached.

  2. High Discharge Rate Electrodeposited Zinc Electrode for Use in Alkaline Microbattery

    Directory of Open Access Journals (Sweden)

    A. L. Nor Hairin

    2012-01-01

    Full Text Available High discharge rate zinc electrode is prepared from electrodeposition process. The electrolytic bath consists of zinc chloride as the metal source and ammonium chloride as the supporting electrolyte. The concentration of the supporting electrolyte is varied from zero until 4 M, while the concentration of zinc chloride is fixed at 2 M. The aim is to produce a porous zinc coating with an enhanced and intimate interfacial area per unit volume. These characteristics shall contribute towards reduced ohmic losses, improved active material utilization, and subsequently producing high rate capacity electrochemical cell. Nitrogen physisorption at 77 K is used to measure the BET surface area and pore volume density of the zinc electrodeposits. The electrodeposited zinc electrodes are then fabricated into alkaline zinc-air microbattery measuring 1 cm2 area x ca. 305 µm thick. The use of inorganic MCM-41 membrane separator enables the fabrication of a compact cell design. The quality of the electrodeposited zinc electrodes is gauged directly from the electrochemical performance of zinc-air cell. Zinc electrodeposits prepared from electrolytic bath of 2 M NH4Cl produces the highest discharge capacity.ABSTRAK: Elektrod zink dengan kadar discas tinggi telah dihasilkan dengan proses saduran elektrokimia. Takungan elektrolit terdiri daripada zink klorida sebagai sumber logam dan ammonium klorida sebagai elektrolit sokongan. Kepekatan elektrolit sokongan diubah daripada sifar hingga 4 M, sementara kepekatan zink klorida ditetapkan pada 2 M. Ini bertujuan untuk mendapatkan saduran zink yang poros dengan luas permukaan per unit isipadu dan sentuhan antaramuka yang dipertingkatkan. Ciri-ciri ini akan menyumbang terhadap pengurangan kehilangan disebabkan kerintangan, pertambahan dalam gunapakai bahan aktif dan akhirnya menghasilkan sel elektrokimia berprestasi tinggi. Physisorpsi nitrogen pada 77 K telah digunakan untuk mengukur luas permukaan BET dan isipadu liang

  3. High rate behavior and discharge limits in micro-pattern detectors

    CERN Document Server

    Bressan, A; Pagano, P; Ropelewski, Leszek; Sauli, Fabio; Biagi, S F; Buzulutskov, A F; Gruwé, M; De Lentdecker, G; Mörmann, D; Sharma, A

    1999-01-01

    We present and discuss a set of systematic measurements, carried out with gaseous proportional micro-pattern detectors, in order to assess their maximum gain when irradiated with high-rate soft X-rays and heavily ionizing alpha particles. The inventory of detectors tested includes: micro-strip micromegas, micro-dot, gas electron multiplier, CAT (compteur à trous), trench (or groove), micro-CAT (or WELL) detectors, as well as systems with two elements of gaseous amplification in cascade. We confirm the general trend of all single-stage detectors to follow Raether's criterion, i.e. a spontaneous transition from avalanche to streamer, followed by a discharge, when the avalanche size reaches a value of a few 10 7 ; a noticeable exception is the micro-dot counter holding more than 10 8. In multiple structures, where the gain under irradiation is increased by at least one order of magnitude; we speculate this to be a consequence of a voltage dependence of Raether's limit, larger for low operating potentials. Our c...

  4. Characterization and Electrochemical Performance at High Discharge Rates of Tin Dioxide Thin Films Synthesized by Atomic Layer Deposition

    Science.gov (United States)

    Maximov, M. Yu.; Novikov, P. A.; Nazarov, D. V.; Rymyantsev, A. M.; Silin, A. O.; Zhang, Y.; Popovich, A. A.

    2017-11-01

    In this study, thin films of tin dioxide have been synthesized on substrates of silicon and stainless steel by atomic layer deposition (ALD) with tetraethyl tin and by inductively coupled remote oxygen plasma as precursors. Studies of the surface morphology by scanning electron microscopy show a strong dependence on synthesis temperature. According to the x-ray photoelectron spectroscopy measurements, the samples contain tin in the oxidation state +4. The thickness of the thin films for electrochemical performance was approximately 80 nm. Electrochemical cycling in the voltage range of 0.01-0.8 V have shown that tin oxide has a stable discharge capacity of approximately 650 mAh/g during 400 charge/discharge cycles with an efficiency of approximately 99.5%. The decrease in capacity after 400 charge/discharge cycles was around 5-7%. Synthesized SnO2 thin films have fast kinetics of lithium ions intercalation and excellent discharge efficiency at high C-rates, up to 40C, with a small decrease in capacity of less than 20%. Specific capacity and cyclic stability of thin films of SnO2 synthesized by ALD exceed the values mentioned in the literature for pure tin dioxide thin films.

  5. Loading effect of a barium titanate artificial interface on high voltage capabilities at high charge and discharge rates

    Science.gov (United States)

    Yoshikawa, Yumi; Teranishi, Takashi; Hayashi, Hidetaka; Kishimoto, Akira

    2017-10-01

    Cyclic characteristics of BaTiO3 (BT)-decorated LiCoO2 (LC), for use as an artificial solid electrolyte interface (SEI) were evaluated at high voltages. Within the standard voltage window (i.e., 3.3-4.2 V), the BT-decorated LC exhibited greater capacities for up to 80 cycles compared with both the Al2O3 (paraelectric)-decorated and bare LC SEIs. The discharge capacity retention after 80 cycles (compared with the initial value) was 86.0% for the BT-LC cathode. This is a significant improvement over both the bare LC that showed 19.9% retention and the Al2O3-LC that displayed 71.5% retention. Thereafter, the cyclic stabilities of the BT-LC and bare LC were compared within potential windows at cutoff voltages as high as 4.9 V. In this region, BT decoration yielded marked improvements in capacity retention after 50 cycles, up to a potential of 4.7 V. The post-situ XRD analysis of the cathode sheets showed that BT decoration effectively stabilized the hexagonal crystal structure of the LC, H1, resulting in the said cyclic stability increase. These observations demonstrate that the use of BT in SEI allows a significant increase in working voltage while maintaining the chemical stability of the underlying LC matrix, a key advancement in the perpetual pursuit of ever higher cell energy densities.

  6. Properties of water surface discharge at different pulse repetition rates

    Science.gov (United States)

    Ruma, Hosseini, S. H. R.; Yoshihara, K.; Akiyama, M.; Sakugawa, T.; Lukeš, P.; Akiyama, H.

    2014-09-01

    The properties of water surface discharge plasma for variety of pulse repetition rates are investigated. A magnetic pulse compression (MPC) pulsed power modulator able to deliver pulse repetition rates up to 1000 Hz, with 0.5 J per pulse energy output at 25 kV, was used as the pulsed power source. Positive pulse with a point-to-plane electrode configuration was used for the experiments. The concentration and production yield of hydrogen peroxide (H2O2) were quantitatively measured and orange II organic dye was treated, to evaluate the chemical properties of the discharge reactor. Experimental results show that the physical and chemical properties of water surface discharge are not influenced by pulse repetition rate, very different from those observed for under water discharge. The production yield of H2O2 and degradation rate per pulse of the dye did not significantly vary at different pulse repetition rates under a constant discharge mode on water surface. In addition, the solution temperature, pH, and conductivity for both water surface and underwater discharge reactors were measured to compare their plasma properties for different pulse repetition rates. The results confirm that surface discharge can be employed at high pulse repetition rates as a reliable and advantageous method for industrial and environmental decontamination applications.

  7. Identification of nano-sized holes by TEM in the graphene layer of graphite and the high rate discharge capability of Li-ion battery anodes

    Energy Technology Data Exchange (ETDEWEB)

    Takamura, Tsutomu [Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Endo, Koji [Department of Chemistry, Rikkyo University, Tokyo 171-8501 (Japan); Fu, Lijun; Wu, Yuping [Department of Chemistry, Fudan University, Shanghai 200433 (China); Lee, Kyeong Jik [SODIFF Advanced Material Co. Ltd., Yeongju, Geongbuk 750-080 (Korea); Matsumoto, Takatoshi [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai (Japan)

    2007-12-20

    SEM images of round-shaped natural graphite, currently widely used as the anode active material of Li-ion batteries, show that the surface mainly consists of the basal plane, which suggests that the Li insertion/extraction reaction rate is quite limited. In contrast to this suggestion, however, the anode of commercial Li-ion batteries is capable of high rate charging/discharging. In order to explain this inconsistency, we propose that there are nano-holes in the graphene layers of the graphite allowing Li to be very easily inserted and extracted via the holes. Prior to the measurements a quantum chemical investigation was performed on the energy required for Li to pass through the hole in a graphene layer (E{sub act}). The results showed that the E{sub act} value is too high when the size is smaller than pyrene, but is fairly low for holes of the size of coronene, implying that Li can pass through the basal plane layer if there is a hole larger than coronene. Characterization of the rounded graphite sample and flaky natural graphite was conducted by constant-current charge/discharge cycle tests, X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM). XRD revealed no appreciable difference between the rounded graphite and flaky natural graphite, in agreement with Raman data. A detailed analysis of the HRTEM results revealed the presence of a number of variously sized circular images. We believe that these are holes in the graphene layer through which Li can pass. The mechanism of formation of the holes is discussed. (author)

  8. Development of C14 laves phase alloy for battery with good high-rate dischargeability; Koritsu hoden tokusei no sugureta denchiyo C14gata laves sogokin no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, H.; Wakao, S. [Tokai Univ., Tokyo (Japan); Mori, K. [Daido Steel Co. Ltd., Aichi (Japan)

    1998-07-05

    Authors have studied to develop Zr-Ti-V-Ni-Mn-Co(Fe,Mo) laves phase alloys for Ni-MH secondary batteries. The object of this study was to develop C14 laves phase alloys with good high-rate dischargeability. Alloys with enthalpy -triangleH for hydride formation in the range of 35 to 37 kJ/molH2 were designed using relations among the enthalpy, cell volume, and average atomic radius. The agreement between designed values and experimental results, and the differences of the enthalpy, cell volume and electrochemical characteristics, alloys with and without heat treatment, were studied. This paper describes first the principle of designing the alloys. Then the method of the experiment was explained The results and considerations were stated under the headings, i.e. Percentage of phase and cell volume, Enthalpy for hydride formation, Electrochemical characteristics of heat treated alloys and the same of as-cast alloys. 12 refs., 5 figs., 3 tabs.

  9. Pulsed high voltage discharge induce hematologic changes

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... The aim of this work to examine the effect of the gas-liquid hybrid discharge treatment system on some hematological ... liquid phase. The high energy plasma arc produces a pressure shock wave, electromagnetic radiations, .... through a 50 kilo-ohm resistor by a negative dc high-voltage power supply and ...

  10. Proposed test method for determining discharge rates from water closets

    DEFF Research Database (Denmark)

    Nielsen, V.; Fjord Jensen, T.

    At present the rates at which discharge takes place from sanitary appliances are mostly known only in the form of estimated average values. SBI has developed a measuring method enabling determination of the exact rate of discharge from a sanitary appliance as function of time. The methods depends...... on the application of a calibrated measuring vessel, the volume of water in the vessel being measured at a given moment by means of a transducer and recorded by an UV recorder which is able to follow very rapid variations. In the article the apparatus is described in detail, and an example is given...

  11. Electing Full Code in Hospice: Patient Characteristics and Live Discharge Rates.

    Science.gov (United States)

    Ankuda, Claire K; Fonger, Evan; O'Neil, Thomas

    2017-09-05

    It is unknown how many hospice enrollees elect to be full code and if this is associated with higher hospice live discharge rates. To measure the rates of hospice enrollees electing full code, the characteristics predicting full code status, and the association of full code status with various hospice live discharge patterns. Retrospective cohort study of electronic medical record data. A total of 25,636 decedents enrolled in two Michigan hospices between 2009 and 2014. Code status was defined as full code versus do-not-resuscitate (DNR) orders. Covariates include demographics, location (home, hospice facility, nursing home, and hospital), primary diagnosis, and length of stay. Hospice live discharge was defined as short (0-14 days), medium (15-179 days), and long (>179 days). A total of 12.9% of hospice enrollees elected full code status. This was significantly (p live discharge compared with those with DNR orders (95% confidence interval [CI] 1.44-2.16) and 2.47 times the odds of short live discharge (95% CI 1.69-3.62) with no significant difference in long live discharge. The association of full code orders with hospice live discharge was stronger for nonwhite enrollees, with a live discharge rate of 23.8% versus 11.6% for African Americans with full code versus DNR orders. Those electing full code status on admission to hospice are at high risk of live hospice discharge after short enrollments, particularly nonwhite enrollees.

  12. Milk Flow Rates from bottle nipples used after hospital discharge.

    Science.gov (United States)

    Pados, Britt Frisk; Park, Jinhee; Thoyre, Suzanne M; Estrem, Hayley; Nix, W Brant

    To test the milk flow rates and variability in flow rates of bottle nipples used after hospital discharge. Twenty-six nipple types that represented 15 common brands as well as variety in price per nipple and store location sold (e.g., Babies R' Us, Walmart, Dollar Store) were chosen for testing. Ten of each nipple type (n = 260 total) were tested by measuring the amount of infant formula expressed in 1 minute using a breast pump. Mean milk flow rate (mL/min) and coefficient of variation (CV) were calculated. Flow rates of nipples within brand were compared statistically. Milk flow rates varied from 1.68 mL/min for the Avent Natural Newborn Flow to 85.34 mL/min for the Dr. Brown's Standard Y-cut. Variability between nipple types also varied widely, from .03 for the Dr. Brown's Standard Level 3 to .37 for MAM Nipple 1 Slow Flow. The extreme range of milk flow rates found may be significant for medically fragile infants being discharged home who are continuing to develop oral feeding skills. The name of the nipple does not provide clear information about the flow rate to guide parents in decision making. Variability in flow rates within nipples of the same type may complicate oral feeding for the medically fragile infant who may not be able to adapt easily to change in flow rates. Both flow rate and variability should be considered when guiding parents to a nipple choice.

  13. Post-discharge surveillance and infection rates in obstetric patients.

    Science.gov (United States)

    Couto, R C; Pedrosa, T M; Nogueira, J M; Gomes, D L; Neto, M F; Rezende, N A

    1998-06-01

    To study the impact of post-discharge surveillance on the detection of nosocomial surgical site infection (SSI) after cesarean section and vaginal delivery. During a 21-month period, all patients attending the obstetrics service in labor were recruited for a observational study on the incidence of SSI. Examinations to detect SSI were performed daily during the hospitalization period and up to 30 days after hospital discharge in an outpatient clinic supervised by the Infection Control Committee. The stratification of risk-factors and the criteria for the diagnosis of SSI were done in accordance with the methods described by the Centers for Disease Control and Prevention. The rates of surgical site infection detected during the hospitalization period were compared with those reported by the Centers for Disease Control and Prevention's National (United States) Nosocomial Infection Surveillance System (CDCNNIS) 'benchmarks'. The incidence of SSI detected by post-discharge outpatient surveillance was compared with that from in-hospital surveillance, for both cesarean section and vaginal delivery. A total of 4463 deliveries were performed during the study period, 2431 (54.5%) by the vaginal route and 2032 (45.5%) by cesarean section. In-hospital surveillance was done on all patients. Post-discharge examinations were done on 951 (46.8%) of the 2032 cesarean section patients. The incidence of SSI in cesarean section detected by in-hospital surveillance was 1.6% (32 cases) and lower than the 3.6% mean rate reported by the CDCNNIS. When SSIs detected by post-discharge surveillance were included, the total number of SSI was 196 cases (9.6%), a value much higher than that for the SSI detected by in-hospital surveillance alone. Only 5 cases (0.21%) of SSI were detected among the 2431 vaginal deliveries. The results of our study demonstrate that most of SSI following cesarean section were detected only after patient's discharge from the hospital and seems to indicate that

  14. Catalytically graphitized glass-like carbon examined as anode for lithium-ion cell performing at high charge/discharge rates

    Energy Technology Data Exchange (ETDEWEB)

    Skowronski, Jan M.; Knofczynski, Krzysztof [Poznan University of Technology, Institute of Chemistry and Technical Electrochemistry, ul. Piotrowo 3, 60-965 Poznan (Poland)

    2009-10-20

    The influence of a long-time heat treatment of hard carbon in the presence of iron catalyst on its structural properties and electrochemical performance is concerned in terms of potential application as anode material for lithium-ion cell. Glass-like carbon spheres obtained by carbonization of phenol resin were catalytically graphitized by heat treatment at temperature 1000 C in argon atmosphere for 20 h and 100 h. After this process iron was completely removed from the product of reaction. The original carbon was entirely useless as anode for Li-ion cell because of its extremely poor reversible capacity (54 mAh g{sup -1}). Due to heat treatment composite materials consisting of microcrystalline graphite admixed with turbostratic carbon were produced. Modified carbons were tested as anode materials using gradually increasing current density. Based on electrochemical measurements a mixed intercalation/insertion mechanism for storage of lithium ions was concluded. Discharge capacity of carbon heat treated for 100 h attained value of 276 mAh g{sup -1} and its reversible capacity appeared to be better than that of flaky graphite upon discharging at current density in the range 50-250 mA g{sup -1}. (author)

  15. 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.

  16. 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.

  17. Thermal analysis of high pressure micro plasma discharge

    Science.gov (United States)

    Mobli, Mostafa

    High pressure micro plasma discharge has been at the center of interest in recent years, because of their vast applications, ease of access and cost efficiency. This attributes to atmospheric discharges that are generated in ambient conditions and therefore can be readily applicable to everyday use. The absence of vacuum makes these high pressure discharges to be inexpensive to operate. Despite the ease of operation, the high pressure is a source of enhanced gas heating as the gas temperature cannot be controlled by diffusion alone. Gas heating is therefore an important factor when it comes to the simulation of high pressure micro plasma discharge, unlike their low pressure counterpart where the heat generation is almost negligible. Low pressure discharge due to their low degree of collisionality generates ionic species and electrons at small concentrations, whereas high pressure discharge due to their higher gas density produces ions and electrons at higher concentrations which is a direct consequence of increase collision. The higher gas density and consequential large concentration of ionic species and electron contributes directly to higher heat generation rates. . In this thesis the gas temperature transport of high pressure micro plasma discharge has been studied with a special focus on the heat source terms, temperature boundary conditions, temperature distribution in the solid phase electrodes and the gas phase and their overall influence on the plasma characteristics. For this purpose a multi-physics mathematical model has been developed that comprised of a plasma module, neutral gas temperature module, external circuit module and conjugate heat transfer module. The plasma module consisted of conservation of the different ionic, electronically excited species, radicals, neutrals and electrons, conservation of the electron temperature, and electric field. The external circuit module resolved the coupled driving circuit comprised of a voltage source, ballast

  18. Milk flow rates from bottle nipples used after hospital discharge

    Science.gov (United States)

    Pados, Britt Frisk; Park, Jinhee; Thoyre, Suzanne M.; Estrem, Hayley; Nix, W. Brant

    2016-01-01

    Purpose To test the milk flow rates and variability in flow rates of bottle nipples used after hospital discharge. Study Design and Methods Twenty-six nipple types that represented 15 common brands as well as variety in price per nipple and store location sold (e.g., Babies R’ Us, Walmart, Dollar Store) were chosen for testing. Ten of each nipple type (n=260 total) were tested by measuring the amount of infant formula expressed in one minute using a breast pump. Mean milk flow rate (mL/min) and coefficient of variation (CV) were calculated. Flow rates of nipples within brand were compared statistically. Results Milk flow rates varied from 1.68 mL/min for the Avent Natural Newborn Flow to 85.34 mL/min for the Dr. Brown’s Standard Y-cut. Variability between nipple types also varied widely, from .03 for the Dr. Brown’s Standard Level 3 to .37 for MAM Nipple 1 Slow Flow. Clinical Implications The extreme range of milk flow rates found may be significant for medically fragile infants being discharged home who are continuing to develop oral feeding skills. The name of the nipple does not provide clear information about the flow rate to guide parents in decision-making. Variability in flow rates within nipples of the same type may complicate oral feeding for the medically fragile infant who may not be able to adapt easily to change in flow rates. Both flow rate and variability should be considered when guiding parents to a nipple choice. PMID:27008466

  19. Characterization of highly transient EUV emitting discharges

    Energy Technology Data Exchange (ETDEWEB)

    Mullen, Joost van der; Kieft, Erik; Broks, Bart [Department of Applied Physics, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven (Netherlands)

    2006-07-15

    The method of disturbed Bilateral Relations (dBR) is used to characterize highly transient plasmas that are used for the generation of Extreme Ultra Violet (EUV), i.e. radiation with a wavelength around 13.5 nm. This dBR method relates equilibrium disturbing to equilibrium restoring processes and follows the degree of equilibrium departure from the global down to the elementary plasma-level. The study gives global values of the electron density and electron temperature. Moreover, it gives a method to construct the atomic state distribution function (ASDF). This ASDF, which is responsible for the spectrum generated by the discharge, is found to be far from equilibrium. There are two reasons for this: first, systems with high charge numbers radiate strongly, second the highly transient behaviour makes that the distribution over the various ionization stages lags behind the temperature evolution.

  20. Charging-discharging system with high power factor, high efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Soo; Joe, Kee Yeon; Byun, Young Bok; Koo, Heun Hoi [Korea Electrotechnology Research Institute (Korea, Republic of)

    1995-07-01

    This paper presents equipment for charging and discharging with high power factor and high efficiency. This equipment is consisted of 3{Phi} SPWM AC/DC converter for improving input current waveform and input power factor, and bidirectional DC/DC converter for electric isolation in the DC link Part. Therefore, Input power factor and the total efficiency in the proposed system can be increased more than in the conventional phase-controlled thyristor charging-discharging System. (author). 7 refs., 14 figs., 1 tab.

  1. Discharge current modes of high power impulse magnetron sputtering

    Directory of Open Access Journals (Sweden)

    Zhongzhen Wu

    2015-09-01

    Full Text Available Based on the production and disappearance of ions and electrons in the high power impulse magnetron sputtering plasma near the target, the expression of the discharge current is derived. Depending on the slope, six possible modes are deduced for the discharge current and the feasibility of each mode is discussed. The discharge parameters and target properties are simplified into the discharge voltage, sputtering yield, and ionization energy which mainly affect the discharge plasma. The relationship between these factors and the discharge current modes is also investigated.

  2. Pulse volume discharges in high pressure gases

    Science.gov (United States)

    Yamshchikov, V. A.

    2015-11-01

    New approach for suppression of plasma inhomogeneities and instabilities in the volume self-sustained discharge is offered. The physical model is offered and conditions of obtaining extremely homogeneous self-sustained discharge are defined (with full suppression of plasma inhomogeneity and instability). Results of calculations agree with experiments.

  3. Pulsed high voltage discharge induce hematologic changes | El ...

    African Journals Online (AJOL)

    The aim of this work to examine the effect of the gas-liquid hybrid discharge treatment system on some hematological parameters. The gas-liquid hybrid discharge (HD) reactor consists of high voltage point discharge electrode above blood surface and cylinderical ground copper electrode containing the blood (in the same ...

  4. High-discharge-rate lithium ion battery

    Science.gov (United States)

    Liu, Gao; Battaglia, Vincent S; Zheng, Honghe

    2014-04-22

    The present invention provides for a lithium ion battery and process for creating such, comprising higher binder to carbon conductor ratios than presently used in the industry. The battery is characterized by much lower interfacial resistances at the anode and cathode as a result of initially mixing a carbon conductor with a binder, then with the active material. Further improvements in cycleability can also be realized by first mixing the carbon conductor with the active material first and then adding the binder.

  5. Improvements in plant growth rate using underwater discharge

    Science.gov (United States)

    Takaki, K.; Takahata, J.; Watanabe, S.; Satta, N.; Yamada, O.; Fujio, T.; Sasaki, Y.

    2013-03-01

    The drainage water from plant pots was irradiated by plasma and then recycled to irrigate plants for improving the growth rate by supplying nutrients to plants and inactivating the bacteria in the bed-soil. Brassica rapa var. perviridis (Chinese cabbage; Brassica campestris) plants were cultivated in pots filled with artificial soil, which included the use of chicken droppings as a fertiliser. The water was recycled once per day from a drainage water pool and added to the bed-soil in the pots. A magnetic compression type pulsed power generator was used to produce underwater discharge with repetition rate of 250 pps. The plasma irradiation times were set as 10 and 20 minutes per day over 28 days of cultivation. The experimental results showed that the growth rate increased significantly with plasma irradiation into the drainage water. The growth rate increased with the plasma irradiation time. The nitrogen concentration of the leaves increased as a result of plasma irradiation based on chlorophyll content analysis. The bacteria in the drainage water were inactivated by the plasma irradiation.

  6. A microscopic investigation into the capacity drop : Impacts of longitudinal behavior on the queue discharge rate

    NARCIS (Netherlands)

    Yuan, K.; Knoop, V.L.; Hoogendoorn, S.P.

    2017-01-01

    The capacity drop indicates that the queue discharge rate is lower than the free-flow capacity. Studies show that the queue discharge rate varies under different traffic conditions. Empirical data show that the queue discharge rate increases as the speed in congestion increases. Insights into the

  7. Modeling Electric Discharges with Entropy Production Rate Principles

    Directory of Open Access Journals (Sweden)

    Thomas Christen

    2009-12-01

    Full Text Available Under which circumstances are variational principles based on entropy production rate useful tools for modeling steady states of electric (gas discharge systems far from equilibrium? It is first shown how various different approaches, as Steenbeck’s minimum voltage and Prigogine’s minimum entropy production rate principles are related to the maximum entropy production rate principle (MEPP. Secondly, three typical examples are discussed, which provide a certain insight in the structure of the models that are candidates for MEPP application. It is then thirdly argued that MEPP, although not being an exact physical law, may provide reasonable model parameter estimates, provided the constraints contain the relevant (nonlinear physical effects and the parameters to be determined are related to disregarded weak constraints that affect mainly global entropy production. Finally, it is additionally conjectured that a further reason for the success of MEPP in certain far from equilibrium systems might be based on a hidden linearity of the underlying kinetic equation(s.

  8. Discharge rates and discharge variability of muscle spindle afferents in human chronic spinal cord injury.

    Science.gov (United States)

    Macefield, Vaughan G

    2013-01-01

    To test the hypothesis that the firing rates and discharge variability of human muscle spindles are not affected by spinal cord injury. Tungsten microelectrodes were inserted into muscle fascicles of the peroneal nerve in six individuals with complete paralysis of the lower limbs following spinal cord injury: 12 afferents were spontaneously active at rest and 7 were recruited during passive muscle stretch. For comparison, recordings were made from 17 spontaneously active and 9 stretch-recruited afferents in 12 intact subjects. Firing rates for the spontaneously active muscle spindles were not significantly different between the spinal (9.8 ± 1.6 Hz) and intact (10.2 ± 1.3 Hz) subjects; the same was true for the stretch-recruited afferents - static firing rates, measured over the final 1s of a ramp-and-hold stretch, were not different between the spinal and intact groups (13.1 ± 3.1% vs 10.0 ± 2.5 Hz). There were also no differences in discharge variability between the spinal and intact subjects, either for the spontaneously active spindles (8.1 ± 2.0% vs 5.7 ± 0.9%) or for the stretch-activated spindles, calculated over the final 1s of static stretch (19.7 ± 5.6% vs 17.0 ± 1.9%). In addition, the responses to stretch imposed manually by the experimenter provided no evidence for an increase in the dynamic response to stretch in the patients. The static stretch sensitivity of human muscle spindles is not affected by chronic spinal cord injury, suggesting that there is no difference in static (and possibly dynamic) fusimotor drive to paralyzed muscles in chronic spinal cord injury. This study provides no evidence for an increase in fusimotor drive as a mechanism for the spasticity associated with chronic spinal injury, though further studies using controlled stretch would be required before it can be concluded that dynamic fusimotor drive is "normal" in these patients. Copyright © 2012 International Federation of Clinical Neurophysiology. Published by

  9. High Efficiency Hall Thruster Discharge Power Converter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Busek leveraged previous, internally sponsored, high power, Hall thruster discharge converter development which allowed it to design, build, and test new printed...

  10. DEM study of granular discharge rate through a vertical pipe with a bend outlet in small absorber sphere system

    Energy Technology Data Exchange (ETDEWEB)

    Li, Tianjin, E-mail: tjli@tsinghua.edu.cn; Zhang, He; Liu, Malin; Huang, Zhiyong; Bo, Hanliang; Dong, Yujie

    2017-04-01

    Highlights: • The work concerns granular flow in a vertical pipe with a bend. • Discharge rate fluctuation in vertical pipe are mainly from velocity fluctuation. • Steady discharge rate decreases rapidly and saturates with μ{sub s} increasing. • Steady discharge rate W{sub s} still obey the 5/2 power law of pipe internal diameter. • A correlation developed for steady discharge rate for this new geometry. - Abstract: Absorber sphere pneumatic conveying is a special application of pneumatic conveying technique in the pebble bed High Temperature Gas-Cooled Reactor (HTGR or HTR). Granular discharge through a vertical pipe with a bend outlet is one of the control modes to determine solid mass flowrate which is an important parameter for the design of absorber sphere pneumatic conveying. Granular discharge rate through the vertical pipe with a bend outlet in the small absorber sphere system are investigated by discrete element method simulation. The effect of geometry parameters on discharge rate, the discharge rate fluctuation in the vertical pipe, and the effect of friction on steady discharge rate (W{sub s}) are analyzed and discussed. The phenomena of discharge rate fluctuation in the vertical pipe are observed, which are mainly resulted from the evolution of the average downward granular velocity. The steady discharge rate decreases rapidly with sliding friction coefficient increasing from 0.125 to 0.5, and gradually saturates with the friction coefficient further increasing from 0.5 to 1. It is interesting that the linear relation between W{sub s}{sup 2/5} and pipe internal diameter D with zero intercept are found for the vertical pipe discharge with a bend outlet, which is different from the orifice discharge through a hopper or silo with none-zero intercept. A correlation similar to Beverloo’s correlation is developed to predict the steady discharge rate through the vertical pipe with a bend outlet. These results are helpful for the design of sphere

  11. High output stomas: ensuring safe discharge from hospital to home.

    Science.gov (United States)

    Smith, Lisa

    High-output stomas are a challenge for the patient and all health professionals involved. This article discusses safe discharge home for this patient group, encouraging collaborative working practices between acute care trust and the community services. The authors also discuss the management of a high-output stoma and preparation and education of the patient before discharge home.

  12. Association of Changing Hospital Readmission Rates With Mortality Rates After Hospital Discharge.

    Science.gov (United States)

    Dharmarajan, Kumar; Wang, Yongfei; Lin, Zhenqiu; Normand, Sharon-Lise T; Ross, Joseph S; Horwitz, Leora I; Desai, Nihar R; Suter, Lisa G; Drye, Elizabeth E; Bernheim, Susannah M; Krumholz, Harlan M

    2017-07-18

    The Affordable Care Act has led to US national reductions in hospital 30-day readmission rates for heart failure (HF), acute myocardial infarction (AMI), and pneumonia. Whether readmission reductions have had the unintended consequence of increasing mortality after hospitalization is unknown. To examine the correlation of paired trends in hospital 30-day readmission rates and hospital 30-day mortality rates after discharge. Retrospective study of Medicare fee-for-service beneficiaries aged 65 years or older hospitalized with HF, AMI, or pneumonia from January 1, 2008, through December 31, 2014. Thirty-day risk-adjusted readmission rate (RARR). Thirty-day RARRs and 30-day risk-adjusted mortality rates (RAMRs) after discharge were calculated for each condition in each month at each hospital in 2008 through 2014. Monthly trends in each hospital's 30-day RARRs and 30-day RAMRs after discharge were examined for each condition. The weighted Pearson correlation coefficient was calculated for hospitals' paired monthly trends in 30-day RARRs and 30-day RAMRs after discharge for each condition. In 2008 through 2014, 2 962 554 hospitalizations for HF, 1 229 939 for AMI, and 2 544 530 for pneumonia were identified at 5016, 4772, and 5057 hospitals, respectively. In January 2008, mean hospital 30-day RARRs and 30-day RAMRs after discharge were 24.6% and 8.4% for HF, 19.3% and 7.6% for AMI, and 18.3% and 8.5% for pneumonia. Hospital 30-day RARRs declined in the aggregate across hospitals from 2008 through 2014; monthly changes in RARRs were -0.053% (95% CI, -0.055% to -0.051%) for HF, -0.044% (95% CI, -0.047% to -0.041%) for AMI, and -0.033% (95% CI, -0.035% to -0.031%) for pneumonia. In contrast, monthly aggregate changes across hospitals in hospital 30-day RAMRs after discharge varied by condition: HF, 0.008% (95% CI, 0.007% to 0.010%); AMI, -0.003% (95% CI, -0.005% to -0.001%); and pneumonia, 0.001% (95% CI, -0.001% to 0.003%). However, correlation coefficients in

  13. Suicide Rates After Discharge From Psychiatric Facilities: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Chung, Daniel Thomas; Ryan, Christopher James; Hadzi-Pavlovic, Dusan; Singh, Swaran Preet; Stanton, Clive; Large, Matthew Michael

    2017-07-01

    High rates of suicide after psychiatric hospitalization are reported in many studies, yet the magnitude of the increases and the factors underlying them remain unclear. To quantify the rates of suicide after discharge from psychiatric facilities and examine what moderates those rates. English-language, peer-reviewed publications published from January 1, 1946, to May 1, 2016, were located using MEDLINE, PsychINFO, and EMBASE with the search terms ((suicid*).ti AND (hospital or discharg* OR inpatient or in-patient OR admit*).ab and ((mortality OR outcome* OR death*) AND (psych* OR mental*)).ti AND (admit* OR admis* or hospital* OR inpatient* OR in-patient* OR discharg*).ab. Hand searching was also done. Studies reporting the number of suicides among patients discharged from psychiatric facilities and the number of exposed person-years and studies from which these data could be calculated. The meta-analysis adhered to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines. A random-effects model was used to calculate a pooled estimate of postdischarge suicides per 100 000 person-years. The suicide rate after discharge from psychiatric facilities was the main outcome, and the association between the duration of follow-up and the year of the sampling were the main a priori moderators. A total of 100 studies reported 183 patient samples (50 samples of females, 49 of males, and 84 of mixed sex; 129 of adults or unspecified patients, 20 of adolescents, 19 of older patients, and 15 from long-term or forensic discharge facilities), including a total of 17 857 suicides during 4 725 445 person-years. The pooled estimate postdischarge suicide rate was 484 suicides per 100 000 person-years (95% CI, 422-555 suicides per 100 000 person-years; prediction interval, 89-2641), with high between-sample heterogeneity (I2 = 98%). The suicide rate was highest within 3 months

  14. Determining the Discharge Rate from a Submerged Oil Leaks using ROV Video and CFD study

    Science.gov (United States)

    Saha, Pankaj; Shaffer, Frank; Shahnam, Mehrdad; Savas, Omer; Devites, Dave; Steffeck, Timothy

    2016-11-01

    The current paper reports a technique to measure the discharge rate by analyzing the video from a Remotely Operated Vehicle (ROV). The technique uses instantaneous images from ROV video to measure the velocity of visible features (turbulent eddies) along the boundary of an oil leak jet and subsequently classical theory of turbulent jets is imposed to determine the discharge rate. The Flow Rate Technical Group (FRTG) Plume Team developed this technique that manually tracked the visible features and produced the first accurate government estimates of the oil discharge rate from the Deepwater Horizon (DWH). For practical application this approach needs automated control. Experiments were conducted at UC Berkeley and OHMSETT that recorded high speed, high resolution video of submerged dye-colored water or oil jets and subsequently, measured the velocity data employing LDA and PIV software. Numerical simulation have been carried out using experimental submerged turbulent oil jets flow conditions employing LES turbulence closure and VOF interface capturing technique in OpenFOAM solver. The CFD results captured jet spreading angle and jet structures in close agreement with the experimental observations. The work was funded by NETL and DOI Bureau of Safety and Environmental Enforcement (BSEE).

  15. Effect of pulsed corona discharge voltage and feed gas flow rate on dissolved ozone concentration

    Energy Technology Data Exchange (ETDEWEB)

    Prasetyaningrum, A., E-mail: ajiprasetyaningrum@gmail.com; Ratnawati,; Jos, B. [Department of Chemical Engineering, Faculty of Engineering, Diponegoro University Jl. Prof. H. Soedarto Tembalang, Semarang, Central Java, Indonesia, 50276 (Indonesia)

    2015-12-29

    Ozonization is one of the methods extensively used for water purification and degradation of organic materials. Ozone (O{sub 3}) is recognized as a powerful oxidizing agent. Due to its strong oxidability and better environmental friendless, ozone increasing being used in domestic and industrial applications. Current technology in ozone production utilizes several techniques (corona discharge, ultra violet radiation and electrolysis). This experiment aimed to evaluating effect of voltage and gas flow rate on ozone production with corona discharge. The system consists of two net-type stainless steel electrode placed in a dielectric barrier. Three pulsed voltage (20, 30, 40 KV) and flow rate (5, 10, 15 L/min) were prepare for operation variable at high frequency (3.7 kHz) with AC pulsed power supply. The dissolved ozone concentration depends on the applied high-voltage level, gas flow rate and the discharge exposure duration. The ozone concentration increases with decreasing gas flow rate. Dissolved ozone concentrations greater than 200 ppm can be obtained with a minimum voltage 40 kV.

  16. High Power laser power conditioning system new discharge circuit research

    CERN Document Server

    Li Yi; Peng Han Sheng; Zhou Pei Zhang; Zheng Wan Guo; Guo Lang Fu; Chen Li Hua; Chen De Hui; Lai Gui You; Luan Yong Ping

    2002-01-01

    The new discharge circuit of power conditioning system for high power laser is studied. The theoretical model of the main discharge circuit is established. The pre-ionization circuit is studied in experiment. In addition, the explosion energy of the new large xenon lamp is successfully measured. The conclusion has been applied to 4 x 2 amplifier system

  17. The suitability of using dissolved gases to determine groundwater discharge to high gradient streams

    Science.gov (United States)

    Gleeson, Tom; Manning, Andrew H.; Popp, Andrea; Zane, Matthew; Clark, Jordan F.

    2018-02-01

    Determining groundwater discharge to streams using dissolved gases is known to be useful over a wide range of streamflow rates but the suitability of dissolved gas methods to determine discharge rates in high gradient mountain streams has not been sufficiently tested, even though headwater streams are critical as ecological habitats and water resources. The aim of this study is to test the suitability of using dissolved gases to determine groundwater discharge rates to high gradient streams by field experiments in a well-characterized, high gradient mountain stream and a literature review. At a reach scale (550 m) we combined stream and groundwater radon activity measurements with an in-stream SF6 tracer test. By means of numerical modeling we determined gas exchange velocities and derived very low groundwater discharge rates (∼15% of streamflow). These groundwater discharge rates are below the uncertainty range of physical streamflow measurements and consistent with temperature, specific conductance and streamflow measured at multiple locations along the reach. At a watershed-scale (4 km), we measured CFC-12 and δ18O concentrations and determined gas exchange velocities and groundwater discharge rates with the same numerical model. The groundwater discharge rates along the 4 km stream reach were highly variable, but were consistent with the values derived in the detailed study reach. Additionally, we synthesized literature values of gas exchange velocities for different stream gradients which show an empirical relationship that will be valuable in planning future dissolved gas studies on streams with various gradients. In sum, we show that multiple dissolved gas tracers can be used to determine groundwater discharge to high gradient mountain streams from reach to watershed scales.

  18. The suitability of using dissolved gases to determine groundwater discharge to high gradient streams

    Science.gov (United States)

    Gleeson, Tom; Manning, Andrew H.; Popp, Andrea; Zane, Mathew; Clark, Jordan F.

    2018-01-01

    Determining groundwater discharge to streams using dissolved gases is known to be useful over a wide range of streamflow rates but the suitability of dissolved gas methods to determine discharge rates in high gradient mountain streams has not been sufficiently tested, even though headwater streams are critical as ecological habitats and water resources. The aim of this study is to test the suitability of using dissolved gases to determine groundwater discharge rates to high gradient streams by field experiments in a well-characterized, high gradient mountain stream and a literature review. At a reach scale (550 m) we combined stream and groundwater radon activity measurements with an in-stream SF6 tracer test. By means of numerical modeling we determined gas exchange velocities and derived very low groundwater discharge rates (∼15% of streamflow). These groundwater discharge rates are below the uncertainty range of physical streamflow measurements and consistent with temperature, specific conductance and streamflow measured at multiple locations along the reach. At a watershed-scale (4 km), we measured CFC-12 and δ18O concentrations and determined gas exchange velocities and groundwater discharge rates with the same numerical model. The groundwater discharge rates along the 4 km stream reach were highly variable, but were consistent with the values derived in the detailed study reach. Additionally, we synthesized literature values of gas exchange velocities for different stream gradients which show an empirical relationship that will be valuable in planning future dissolved gas studies on streams with various gradients. In sum, we show that multiple dissolved gas tracers can be used to determine groundwater discharge to high gradient mountain streams from reach to watershed scales.

  19. High Input Voltage Hall Thruster Discharge Converter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall scope of this Phase I/II effort is the development of a high efficiency 15kW (nominal) Hall thruster discharge converter. In Phase I, Busek Co. Inc. will...

  20. Insulator Degradation by High Current Discharges

    Science.gov (United States)

    Engel, Thomas Gregory

    1990-08-01

    The degenerative action produced by 300 kA, repetitive arc discharges on the surface of various insulator materials is investigated as a function of insulator and electrode material and the ambient atmosphere used. The insulator damage produced by the 20 mus wide oscillating pulse is characterized by a shot-to-shot decrease in surface breakdown voltage of the insulator and a loss of insulator mass. The insulators under investigation include a broad group of ceramic, polymeric, and elastomeric materials which have been tested with graphite, molybdenum, copper, and copper-tungsten electrodes. Typically, the ambient gas used in the tests was atmospheric air although some tests were conducted in pure nitrogen, pure oxygen, and admixtures thereof. Models have also been developed which predict holdoff voltage degradation, mass erosion, and holdoff voltage conditioning for the insulator. The conditioning of an insulator is characterized by an increase in its surface holdoff voltage in the initial stages of the test. In these models, insulator performance is predicted by its HDR (i.e., holdoff voltage degradation resistance), MVC (mass vaporization coefficient), and HVC (holdoff voltage conditioning) figures of merit which are calculated using the pertinent thermophysical properties of the material. The relationship between the figures of merit is also discussed.

  1. High-voltage discharge in supersonic jet of plumbum vapor

    Science.gov (United States)

    Amirov, R. Kh; Antonov, N. N.; Liziakin, G. D.; Polistchook, V. P.; Samoylov, I. S.; Usmanov, R. A.; Yartsev, I. M.

    2015-11-01

    During study of vacuum discharge in plumbum evaporating from molybdenum crucible in identical geometry of discharge gap and the same crucible temperature existence of two different discharge forms were observed. These two forms are vacuum arc with current above 10 A and voltage about 15 V and high-voltage discharge with current about 10 mA and voltage of 340 V. Plumbum was placed in heat-isolated crucible (cathode). Electron-beam heater was situated under the crucible. At the temperature of 1.25 kK that corresponds to plumbum saturated vapor pressure about 0.1 kPa voltage from power source (380 V, 200 A) was applied to anode and high-voltage discharge initiated with characteristics mentioned above. After a few seconds this discharge could turn into arc or could exist hundreds of seconds until total plumbum evaporation. Glow of discharge could take the form of a cone, harness or plasma bunch that hanged at the appreciable distance from the electrodes. The estimations of plasma parameters are presented.

  2. 46 CFR 108.441 - Piping and discharge rates for CO2 systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Piping and discharge rates for CO2 systems. 108.441... Systems § 108.441 Piping and discharge rates for CO2 systems. (a) The size of branch lines to spaces protected by a CO2 system must meet Table 108.441. (b) Distribution piping within a space must be...

  3. A Medical Resident-Pharmacist Collaboration Improves the Rate of Medication Reconciliation Verification at Discharge.

    Science.gov (United States)

    Caroff, Daniel A; Bittermann, Therese; Leonard, Charles E; Gibson, Gene A; Myers, Jennifer S

    2015-10-01

    At the Hospital of the University of Pennsylvania (Philadelphia), it is standard practice to perform medication reconciliation at patient discharge. Although pharmacists historically were available to assist resident physicians in the discharge medication reconciliation process, the process was never standardized. An internal review showed a 60%-70% rate of pharmacist review of discharge medication lists, potentially enabling medication errors to go unnoticed during transitions of care. In response, a medical resident- and pharmacist-led collaboration was designed, and a pre-post-intervention study was conducted to assess its effectiveness. A new work flow was established in which house staff notified pharmacists when a preliminary discharge medication list was ready for reconciliation and provided access for pharmacists to correct medication errors in the electronic discharge document with physician approval. Length of stay, average time of day of patient discharge, and readmission data were compared in the pre- and post-intervention periods. There were 981 discharges in the preintervention period and 1,207 in the postintervention period. The rate of pharmacist reconciliation increased from 64.0% to 82.4% after the intervention (pdischarge (ptime of discharge after the intervention. Redesigning the discharge medication reconciliation process in a teaching hospital to include a review of medical resident discharge medication lists by pharmacists provided more opportunities for discharge medication error identification and correction.

  4. Calculation of the inventory and near-field release rates of radioactivity from neutron-activated metal parts discharged from the high flux isotope reactor and emplaced in solid waste storage area 6 at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Kelmers, A.D.; Hightower, J.R.

    1987-05-01

    Emplacement of contaminated reactor components involves disposal in lined and unlined auger holes in soil above the water table. The radionuclide inventory of disposed components was calculated. Information on the composition and weight of the components, as well as reasonable assumptions for the neutron flux fueling use, the time of neutron exposure, and radioactive decay after discharge, were employed in the inventory calculation. Near-field release rates of /sup 152/Eu, /sup 154/Eu, and /sup 155/Eu from control plates and cylinders were calculated for 50 years after emplacement. Release rates of the europium isotopes were uncertain. Two release-rate-limiting models were considered and a range of reasonable values were assumed for the time-to-failure of the auger-hole linear and aluminum cladding and europium solubility in SWSA-6 groundwater. The bounding europium radionuclide near-field release rates peaked at about 1.3 Ci/year total for /sup 152,154,155/Eu in 1987 for the lower bound, and at about 420 Ci/year in 1992 for the upper bound. The near-field release rates of /sup 55/Fe, /sup 59/Ni, /sup 60/Co, and /sup 63/Ni from stainless steel and cobalt alloy components, as well as of /sup 10/Be, /sup 41/Ca, and /sup 55/Fe from beryllium reflectors, were calculated for the next 100 years, assuming bulk waste corrosion was the release-rate-limiting step. Under the most conservative assumptions for the reflectors, the current (1986) total radionuclide release rate was calculated to be about 1.2 x 10/sup -4/ Ci/year, decreasing by 1992 to a steady release of about 1.5 x 10/sup -5/ Ci/year due primarily to /sup 41/Ca. 50 refs., 13 figs., 8 tabs.

  5. Discharges during U.S. Army basic training: injury rates and risk factors.

    Science.gov (United States)

    Knapik, J J; Canham-Chervak, M; Hauret, K; Hoedebecke, E; Laurin, M J; Cuthie, J

    2001-07-01

    This study examined injury rates and risk factors for discharge in a cohort of 756 men and 474 women in U.S. Army basic combat training (BCT) at Fort Jackson, South Carolina. Investigators systematically screened trainee medical records for injuries and collected medical recommendations to temporarily remove a trainee from BCT to allow recovery from an injury. The BCT unit provided Army Physical Fitness Test (APFT) scores and trainee demographic data. Discharges were identified by reviewing discharge packets and were confirmed through rosters from the BCT units. There were 102 men and 108 women discharged. Person-time injury incidence rates (for time-loss injuries) among discharged and nondischarged men were 1.87 and 0.45 cases/100 person-days, respectively (p APFT events, and lower educational level. Women with more body mass or a higher body mass index also had a marginally higher risk of discharge.

  6. High Input Voltage Discharge Supply for High Power Hall Thrusters Using Silicon Carbide Devices

    Science.gov (United States)

    Pinero, Luis R.; Scheidegger, Robert J.; Aulsio, Michael V.; Birchenough, Arthur G.

    2014-01-01

    A power processing unit for a 15 kW Hall thruster is under development at NASA Glenn Research Center. The unit produces up to 400 VDC with two parallel 7.5 kW discharge modules that operate from a 300 VDC nominal input voltage. Silicon carbide MOSFETs and diodes were used in this design because they were the best choice to handle the high voltage stress while delivering high efficiency and low specific mass. Efficiencies in excess of 97 percent were demonstrated during integration testing with the NASA-300M 20 kW Hall thruster. Electromagnet, cathode keeper, and heater supplies were also developed and will be integrated with the discharge supply into a vacuum-rated brassboard power processing unit with full flight functionality. This design could be evolved into a flight unit for future missions that requires high power electric propulsion.

  7. Early Stage of Pulsed High Current Discharge with Copper Powder

    Science.gov (United States)

    Yokoyama, Takuma; Kuraoka, Takuya; Takano, Kazuya; Ibuka, Shinji; Yasuoka, Koichi; Ishii, Shozo

    Early phase of powder plasmas powered by a pulsed high current discharge was examined by use of high-speed cameras and a laser shadowgraph and schlieren techniques. Initial electrons created by a pre-ionization discharge collide with both an anode and powder particles, of which surfaces evaporate after then. Evaporation of the particle by electron collision initially occured in the hemisphere surface which is close to cathode side. Since vaporization of the anode far exceeds that of the particles, discharge characteristics is almost similar to that of vacuum sparks in which expanding anode plasmas are observed. In order to suppress the developpment of the anode plasma, reduction of the effective anode area by varying the anode shape was examined.

  8. Improvement of growth rate of plants by bubble discharge in water

    Science.gov (United States)

    Takahata, Junichiro; Takaki, Koichi; Satta, Naoya; Takahashi, Katsuyuki; Fujio, Takuya; Sasaki, Yuji

    2015-01-01

    The effect of bubble discharge in water on the growth rate of plants was investigated experimentally for application to plant cultivation systems. Spinach (Spinacia oleracea), radish (Raphanus sativus var. sativus), and strawberry (Fragaria × ananassa) were used as specimens to clarify the effect of the discharge treatment on edible parts of the plants. The specimens were cultivated in pots filled with artificial soil, which included chicken manure charcoal. Distilled water was sprayed on the artificial soil and drained through a hole in the pots to a water storage tank. The water was circulated from the water storage tank to the cultivation pots after 15 or 30 min discharge treatment on alternate days. A magnetic compression-type pulsed power generator was used to produce the bubble discharge with a repetition rate of 250 pps. The plant height in the growth phase and the dry weight of the harvested plants were improved markedly by the discharge treatment in water. The soil and plant analyzer development (SPAD) value of the plants also improved in the growth phase of the plants. The concentration of nitrate nitrogen, which mainly contributed to the improvement of the growth rate, in the water increased with the discharge treatment. The Brix value of edible parts of Fragaria × ananassa increased with the discharge treatment. The inactivation of bacteria in the water was also confirmed with the discharge treatment.

  9. High-order harmonic generation in a capillary discharge

    Science.gov (United States)

    Rocca, Jorge J.; Kapteyn, Henry C.; Mumane, Margaret M.; Gaudiosi, David; Grisham, Michael E.; Popmintchev, Tenio V.; Reagan, Brendan A.

    2010-06-01

    A pre-ionized medium created by a capillary discharge results in more efficient use of laser energy in high-order harmonic generation (HHG) from ions. It extends the cutoff photon energy, and reduces the distortion of the laser pulse as it propagates down the waveguide. The observed enhancements result from a combination of reduced ionization energy loss and reduced ionization-induced defocusing of the driving laser as well as waveguiding of the driving laser pulse. The discharge plasma also provides a means to spectrally tune the harmonics by tailoring the initial level of ionization of the medium.

  10. High order fluid model for ionization fronts in streamer discharges

    NARCIS (Netherlands)

    A. Markosyan (Aram); S. Dujko (Sasa); W. Hundsdorfer (Willem); U. Ebert (Ute)

    2011-01-01

    htmlabstractWhen non-ionized or lowly ionized matter is exposed to high electric fields, non-equilibrium ionization processes, streamer discharges, can develop. Streamers occur in nature and as well in many industrial applications such as the treatment of exhaust gasses, polluted water or biogas. A

  11. Effects of Gas Flow Rate on the Discharge Characteristics of a DC Excited Plasma Jet

    Science.gov (United States)

    Li, Xuechen; Jia, Pengying; Di, Cong; Bao, Wenting; Zhang, Chunyan

    2015-09-01

    A direct current (DC) source excited plasma jet consisting of a hollow needle anode and a plate cathode has been developed to form a diffuse discharge plume in ambient air with flowing argon as the working gas. Using optical and electrical methods, the discharge characteristics are investigated for the diffuse plasma plume. Results indicate that the discharge has a pulse characteristic, under the excitation of a DC voltage. The discharge pulse corresponds to the propagation process of a plasma bullet travelling from the anode to the cathode. It is found that, with an increment of the gas flow rate, both the discharge plume length and the current peak value of the pulsed discharge decrease in the laminar flow mode, reach their minima at about 1.5 L/min, and then slightly increase in the turbulent mode. However, the frequency of the pulsed discharge increases in the laminar mode with increasing the argon flow rate until the argon flow rate equals to about 1.5 L/min, and then slightly decreases in the turbulent mode. supported by National Natural Science Foundation of China (Nos. 10805013, 11375051), Funds for Distinguished Young Scientists of Hebei Province, China (No. A2012201045), Department of Education for Outstanding Youth Project of China (No. Y2011120), and Youth Project of Hebei University of China (No. 2011Q14)

  12. High-Rate Capable Floating Strip Micromegas

    Science.gov (United States)

    Bortfeldt, Jonathan; Bender, Michael; Biebel, Otmar; Danger, Helge; Flierl, Bernhard; Hertenberger, Ralf; Lösel, Philipp; Moll, Samuel; Parodi, Katia; Rinaldi, Ilaria; Ruschke, Alexander; Zibell, André

    2016-04-01

    We report on the optimization of discharge insensitive floating strip Micromegas (MICRO-MEsh GASeous) detectors, fit for use in high-energy muon spectrometers. The suitability of these detectors for particle tracking is shown in high-background environments and at very high particle fluxes up to 60 MHz/cm2. Measurement and simulation of the microscopic discharge behavior have demonstrated the excellent discharge tolerance. A floating strip Micromegas with an active area of 48 cm × 50 cm with 1920 copper anode strips exhibits in 120 GeV pion beams a spatial resolution of 50 μm at detection efficiencies above 95%. Pulse height, spatial resolution and detection efficiency are homogeneous over the detector. Reconstruction of particle track inclination in a single detector plane is discussed, optimum angular resolutions below 5° are observed. Systematic deviations of this μTPC-method are fully understood. The reconstruction capabilities for minimum ionizing muons are investigated in a 6.4 cm × 6.4 cm floating strip Micromegas under intense background irradiation of the whole active area with 20 MeV protons at a rate of 550 kHz. The spatial resolution for muons is not distorted by space charge effects. A 6.4 cm × 6.4 cm floating strip Micromegas doublet with low material budget is investigated in highly ionizing proton and carbon ion beams at particle rates between 2 MHz and 2 GHz. Stable operation up to the highest rates is observed, spatial resolution, detection efficiencies, the multi-hit and high-rate capability are discussed.

  13. Global Modeling of N2O Discharges: Rate Coefficients and Comparison with ICP and Glow Discharges Results

    Directory of Open Access Journals (Sweden)

    Konstantinos Katsonis

    2013-01-01

    Full Text Available We developed a Global Model for N2O plasmas valid for applications in various power, gas flow rate, and pressure regimes. Besides energy losses from electron collisions with N2O, it takes into consideration those due to molecular N2 and O2 and to atomic N and O species. Positive atomic N+ and O+ and molecular N2O+, N2+, and O2+ have been treated as separate species and also negative O− ions. The latter confer an electronegative character to the discharge, calling for modified plasma sheath and plasma potential formulas. Electron density and temperature and all species densities have been evaluated, hence the ionization and dissociation percentages of N2O, N2, and O2 molecules and the plasma electronegativity. The model is extended to deal with N2/O2 mixtures feedings, notably with air. Rate coefficients and model results are discussed and compared with those from available theoretical and experimental work on ICP and glow discharge devices.

  14. Association of high-volume hospitals with greater likelihood of discharge to home following colorectal surgery.

    Science.gov (United States)

    Balentine, Courtney J; Naik, Aanand D; Robinson, Celia N; Petersen, Nancy J; Chen, G John; Berger, David H; Anaya, Daniel A

    2014-03-01

    Discharge disposition is a patient-centered quality metric that reflects differences in quality of life and recovery following surgery. The effect of hospital volume on quality of recovery measured by rates of successful discharge to home remains unclear. To test the hypothesis that patients having colorectal surgery at high-volume hospitals would more likely be discharged to home rather than discharged to skilled rehabilitation facilities to complete recovery. Longitudinal analysis of 2008 hospital inpatient data to identify patients undergoing colorectal surgery who survived to discharge. The setting was the Nationwide Inpatient Sample, the largest all-payer inpatient care database, containing data from more than 1000 hospitals. Participants were 280,644 patients (≥ 18 years) who underwent colorectal resections for benign or malignant disease and survived to discharge. The primary end point was discharge to home (with or without home health care) vs discharge to skilled facilities (skilled nursing, short-term recovery, or rehabilitation hospitals or other institutions). The secondary end point was discharge to home with home health care rather than to a skilled facility for patients with postdischarge care needs. Multiple logistic regression using robust standard errors was used to compute the odds ratios of each outcome based on hospital volume, while adjusting for other important variables. The odds of discharge to home vs discharge to skilled facilities were significantly greater in high-volume hospitals compared with low-volume hospitals (odds ratio, 2.09; 95% CI, 1.70-2.56), with an absolute increase of 9%. For patients with postdischarge care needs, high-volume hospitals were less likely than low-volume hospitals to use skilled facilities rather than home health care (odds ratio, 0.35; 95% CI, 0.27-0.45), with an absolute difference of 10%. Patients having colorectal surgery at high-volume hospitals are significantly more likely to recover and return home

  15. Real-time operational feedback: daily discharge rate as a novel hospital efficiency metric.

    Science.gov (United States)

    Wong, Hannah J; Wu, Robert C; Caesar, Michael; Abrams, Howard; Morra, Dante

    2010-12-01

    Part of delivering quality care means providing it in a timely, efficient manner. Improving the efficiency of care requires measurement. The selection of appropriate indicators that are valid and responsive is crucial to focus improvement initiatives. Indicators of operational efficiency should be conceptually simple, generated in real time, calculated using readily available hospital administrative data, sufficiently granular to reveal detail needed to focus improvement, and correlate with other valid indicators of operational efficiency. In this paper, the authors propose daily discharge rate as a novel real-time metric of hospital operational discharge efficiency and compare it with average length of stay. The authors also suggest the use of control charts as an effective way to present daily discharge rate data to clinicians and managers in real time to prompt actionable improvements in discharge efficiency. The authors conclude that daily discharge rate has the potential to drive timely improvements in the discharge process and warrants consideration and further study by others interested in improving hospital operational efficiency and the delivery of quality care.

  16. Light and Light Sources High-Intensity Discharge Lamps

    CERN Document Server

    Flesch, Peter G

    2006-01-01

    Light and Light Sources gives an introduction to the working principles of high-intensity discharge (HID) lamps and points out challenges and problems associated with the development and operation of HID lamps. The state-of-the-art in electrode and plasma diagnostics as well as numerical methods used for the understanding of HID lamps are described. This volume addresses students as well as scientists and researchers at universities and in industry.

  17. Kinetics of high pressure argon-helium pulsed gas discharge

    Science.gov (United States)

    Emmons, D. J.; Weeks, D. E.

    2017-05-01

    Simulations of a pulsed direct current discharge are performed for a 7% argon in helium mixture at a pressure of 270 Torr using both zero- and one-dimensional models. Kinetics of species relevant to the operation of an optically pumped rare-gas laser are analyzed throughout the pulse duration to identify key reaction pathways. Time dependent densities, electron temperatures, current densities, and reduced electric fields in the positive column are analyzed over a single 20 μs pulse, showing temporal agreement between the two models. Through the use of a robust reaction rate package, radiation trapping is determined to play a key role in reducing A r (1 s5) metastable loss rates through the reaction sequence A r (1 s5)+e-→A r (1 s4)+e- followed by A r (1 s4)→A r +ℏω . Collisions with He are observed to be responsible for A r (2 p9) mixing, with nearly equal rates to A r (2 p10) and A r (2 p8) . Additionally, dissociative recombination of A r2+ is determined to be the dominant electron loss mechanism for the simulated discharge conditions and cavity size.

  18. High intensity Discharge lighting; Alumbrado de alta intensidad de descarga

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza E, Ernesto J. [Manufacturera de Reactores, S. A., Mexico, D. F. (Mexico)

    1993-12-31

    This paper gets into contact with some fundamentals in the operation of high discharge intensity lamps. There are useful definitions, as well as the study of the operation of high pressure sodium lamps and of metallic additives operating at less than nominal power. [Espanol] Este trabajo pone al lector en contacto con algunos fundamentos de la operacion de las lamparas de alta intensidad de descarga (HID). Se encuentra con definiciones utiles, asi como el estudio de la operacion de las lamparas de sodio en alta presion y de aditivos metalicos operando a una potencia menor que la nominal.

  19. Contribution of snow and glacier melt to discharge for highly glacierised catchments in Norway

    National Research Council Canada - National Science Library

    Engelhardt, M; Schuler, T. V; Andreassen, L. M

    2014-01-01

    .... Calibration and validation were performed for each catchment based on measurements of seasonal glacier mass balances and daily discharge rates, as additional validation data served daily melt rates...

  20. Simple estimate of entrainment rate of pollutants from a coastal discharge into the surf zone.

    Science.gov (United States)

    Wong, Simon H C; Monismith, Stephen G; Boehm, Alexandria B

    2013-10-15

    Microbial pollutants from coastal discharges can increase illness risks for swimmers and cause beach advisories. There is presently no predictive model for estimating the entrainment of pollution from coastal discharges into the surf zone. We present a novel, quantitative framework for estimating surf zone entrainment of pollution at a wave-dominant open beach. Using physical arguments, we identify a dimensionless parameter equal to the quotient of the surf zone width l(sz) and the cross-flow length scale of the discharge la = M(j) (1/2)/U(sz), where M(j) is the discharge's momentum flux and U(sz) is a representative alongshore velocity in the surf zone. We conducted numerical modeling of a nonbuoyant discharge at an alongshore uniform beach with constant slope using a wave-resolving hydrodynamic model. Using results from 144 numerical experiments we develop an empirical relationship between the surf zone entrainment rate α and l(sz)/(la). The empirical relationship can reasonably explain seven measurements of surf zone entrainment at three diverse coastal discharges. This predictive relationship can be a useful tool in coastal water quality management and can be used to develop predictive beach water quality models.

  1. Impact Of Particle Agglomeration On Accumulation Rates In The Glass Discharge Riser Of HLW Melter

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, A. A. [Department of Energy, Office of River Protection, Richland, WA (United States); Rodriguez, C. A. [Pacific Northwest National Laboratory, Richland, WA (United States); Matyas, J. [Pacific Northwest National Laboratory, Richland, WA (United States); Owen, A. T. [Pacific Northwest National Laboratory, Richland, WA (United States); Jansik, D. P. [Pacific Northwest National Laboratory, Richland, WA (United States); Lang, J. B. [Pacific Northwest National Laboratory, Richland, WA (United States)

    2012-11-12

    The major factor limiting waste loading in continuous high-level radioactive waste (HLW) melters is an accumulation of particles in the glass discharge riser during a frequent and periodic idling of more than 20 days. An excessive accumulation can produce robust layers a few centimeters thick, which may clog the riser, preventing molten glass from being poured into canisters. Since the accumulation rate is driven by the size of particles we investigated with x-ray microtomography, scanning electron microscopy, and image analysis the impact of spinel forming components, noble metals, and alumina on the size, concentration, and spatial distribution of particles, and on the accumulation rate. Increased concentrations of Fe and Ni in the baseline glass resulted in the formation of large agglomerates that grew over the time to an average size of ~185+-155 {mu}m, and produced >3 mm thick layer after 120 h at 850 deg C. The noble metals decreased the particle size, and therefore significantly slowed down the accumulation rate. Addition of alumina resulted in the formation of a network of spinel dendrites which prevented accumulation of particles into compact layers.

  2. IMPACT OF PARTICLE AGGLOMERATION ON ACCUMULATION RATES IN THE GLASS DISCHARGE RISER OF HLW MELTER

    Energy Technology Data Exchange (ETDEWEB)

    Matyas, Josef; Jansik, Danielle P.; Owen, Antionette T.; Rodriguez, Carmen P.; Lang, Jesse B.; Kruger, Albert A.

    2013-08-05

    The major factor limiting waste loading in continuous high-level radioactive waste (HLW) melters is an accumulation of particles in the glass discharge riser during a frequent and periodic idling of more than 20 days. An excessive accumulation can produce robust layers a few centimeters thick, which may clog the riser, preventing molten glass from being poured into canisters. Since the accumulation rate is driven by the size of particles we investigated with X-ray microtomography, scanning electron microscopy, and image analysis the impact of spinel forming components, noble metals, and alumina on the size, concentration, and spatial distribution of particles, and on the accumulation rate. Increased concentrations of Fe and Ni in the baseline glass resulted in the formation of large agglomerates that grew over the time to an average size of ~185±155 µm, and produced >3 mm thick layer after 120 h at 850 °C. The noble metals decreased the particle size, and therefore significantly slowed down the accumulation rate. Addition of alumina resulted in the formation of a network of spinel dendrites which prevented accumulation of particles into compact layers.

  3. Strength training, but not endurance training, reduces motor unit discharge rate variability.

    Science.gov (United States)

    Vila-Chã, Carolina; Falla, Deborah

    2016-02-01

    This study evaluates and compares the effects of strength and endurance training on motor unit discharge rate variability and force steadiness of knee extensor muscles. Thirty sedentary healthy men (age, 26.0±3.8yrs) were randomly assigned to strength training, endurance training or a control group. Conventional endurance and strength training was performed 3days per week, over a period of 6weeks. Maximum voluntary contraction (MVC), time to task failure (at 30% MVC), coefficient of variation (CoV) of force and of the discharges rates of motor units from the vastus medialis obliquus and vastus lateralis were determined as subjects performed 20% and 30% MVC knee extension contractions before and after training. CoV of motor unit discharges rates was significantly reduced for both muscles following strength training (Pendurance (P=0.875) or control group (P=0.995). CoV of force was reduced after the strength training intervention only (Ptraining, but not endurance training, reduces motor unit discharge rate variability and enhances force steadiness of the knee extensors. These results provide new insights into the neuromuscular adaptations that occur with different training methods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Age-related decreases in motor unit discharge rate and force control during isometric plantar flexion

    DEFF Research Database (Denmark)

    Kallio, J; Søgaard, Karen; Avela, J

    2012-01-01

    Aging is related to multiple changes in muscle physiology and function. Previous findings concerning the effects of aging on motor unit discharge rate (DR) and fluctuations in DR and force are somewhat contradictory. Eight YOUNG and nine OLD physically active males performed isometric ramp (RECR)...

  5. A differential equation for the flow rate during silo discharge: Beyond the Beverloo rule

    Directory of Open Access Journals (Sweden)

    Madrid Marcos A.

    2017-01-01

    Full Text Available We present a differential equation for the flow rate of granular materials during the discharge of a silo. This is based in the energy balance of the variable mass system in contrast with the traditional derivations based on heuristic postulates such as the free fall arch. We show that this new equation is consistent with the well known Beverloo rule, providing an independent estimate for the universal Beverloo prefactor. We also find an analytic expression for the pressure under discharging conditions.

  6. Towards Stable Lithium-Sulfur Batteries with a Low Self-Discharge Rate: Ion Diffusion Modulation and Anode Protection.

    Science.gov (United States)

    Xu, Wen-Tao; Peng, Hong-Jie; Huang, Jia-Qi; Zhao, Chen-Zi; Cheng, Xin-Bing; Zhang, Qiang

    2015-09-07

    The self-discharge of a lithium-sulfur cell decreases the shelf-life of the battery and is one of the bottlenecks that hinders its practical applications. New insights into both the internal chemical reactions in a lithium-sulfur system and effective routes to retard self-discharge for highly stable batteries are crucial for the design of lithium-sulfur cells. Herein, a lithium-sulfur cell with a carbon nanotube/sulfur cathode and lithium-metal anode in lithium bis(trifluoromethanesulfonyl)imide/1,3-dioxolane/dimethyl ether electrolyte was selected as the model system to investigate the self-discharge behavior. Both lithium anode passivation and polysulfide anion diffusion suppression strategies are applied to reduce self-discharge of the lithium-sulfur cell. When the lithium-metal anode is protected by a high density passivation layer induced by LiNO3 , a very low shuttle constant of 0.017 h(-1) is achieved. The diffusion of the polysulfides is retarded by an ion-selective separator, and the shuttle constants decreased. The cell with LiNO3 additive maintained a discharge capacity of 97 % (961 mAh g(-1) ) of the initial capacity after 120 days at open circuit, which was around three times higher than the routine cell (32 % of initial capacity, corresponding to 320 mAh g(-1) ). It is expected that lithium-sulfur batteries with ultralow self-discharge rates may be fabricated through a combination of anode passivation and polysulfide shuttle control, as well as optimization of the lithium-sulfur cell configuration. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Mortality, Rehospitalisation and Violent Crime in Forensic Psychiatric Patients Discharged from Hospital: Rates and Risk Factors.

    Directory of Open Access Journals (Sweden)

    Seena Fazel

    Full Text Available To determine rates and risk factors for adverse outcomes in patients discharged from forensic psychiatric services.We conducted a historical cohort study of all 6,520 psychiatric patients discharged from forensic psychiatric hospitals between 1973 and 2009 in Sweden. We calculated hazard ratios for mortality, rehospitalisation, and violent crime using Cox regression to investigate the effect of different psychiatric diagnoses and two comorbidities (personality or substance use disorder on outcomes.Over mean follow-up of 15.6 years, 30% of patients died (n = 1,949 after discharge with an average age at death of 52 years. Over two-thirds were rehospitalised (n = 4,472, 69%, and 40% violently offended after discharge (n = 2,613 with a mean time to violent crime of 4.2 years. The association between psychiatric diagnosis and outcome varied-substance use disorder as a primary diagnosis was associated with highest risk of mortality and rehospitalisation, and personality disorder was linked with the highest risk of violent offending. Furthermore comorbid substance use disorder typically increased risk of adverse outcomes.Violent offending, premature mortality and rehospitalisation are prevalent in patients discharged from forensic psychiatric hospitals. Individualised treatment plans for such patients should take into account primary and comorbid psychiatric diagnoses.

  8. 78 FR 13566 - Energy Conservation Program for High-Intensity Discharge Lamps: Public Meeting and Availability...

    Science.gov (United States)

    2013-02-28

    ... Part 431 RIN 1904-AC36 Energy Conservation Program for High-Intensity Discharge Lamps: Public Meeting... conservation standards for high-intensity discharge (HID) lamps. The meeting will cover the analytical... High-Intensity Discharge Lamps, EERE-2010-BT-STD-0043 and/or RIN 1904-AC36, 1000 Independence Avenue SW...

  9. High performance discharges and capabilities in Alcator C-Mod

    Energy Technology Data Exchange (ETDEWEB)

    Porkolab, M.

    1996-12-01

    Alcator C-Mod is a compact, diverted, shaped, high magnetic field (B = 9 T) tokamak operating at the Massachusetts Institute of Technology Plasma Fusion Center. The machine interior is all metallic, and the walls and divertor region are covered with molybdenum tiles. The vacuum vessel is a continuous, thick wall stainless steel construction, prototypical of future fusion devices (e.g., ITER). Typical discharge cleaning utilizes ECDC, or electron-cyclotron discharge cleaning, in the steady state at low magnetic field (0.0875 T). While its dimensions are compact (R = 0.67 m, a = 0.22 m, K = 1.8), C-Mod is designed to operate up to 2.5 MA at 9.0 T magnetic field. To present date the machine has operated at currents up to 1.5 MA at B = 5.3 T, and magnetic fields up to 8.0 T at I{sub p} = 1.2 MA. Due to the high current density, line average densities of 4.0 x 10{sup 20} m{sup {minus}3} are obtained with gas fueling, and peak densities in excess of 1.0 x 10{sup 21} m{sup {minus}3} have been obtained with pellet fueling. Typical pulse lengths are up to 2.0 seconds, with a flat-top of typically 1.0 sec. Presently the device is equipped with 4.0 MW of ICRF heating power operating at 80 MHz, but this capability is being upgraded to 8.0 MW with the addition of 4.0 MW of tunable ICRF power operating at 40.80 MHz. A 20 pellet/pulse deuterium injector is operational, and a 4 pellet Li injector is also operational. To reduce the influx of metallic impurities during high power operation, recently boronization of the machine interior was begun prior to plasma discharges, this allowed plasma operation with full auxiliary power capability without excessive radiative power losses from the plasma core. 7 refs.

  10. Organisation and features of hospital, intermediate care and social services in English sites with low rates of delayed discharge.

    Science.gov (United States)

    Baumann, Matt; Evans, Sherrill; Perkins, Margaret; Curtis, Lesley; Netten, Ann; Fernandez, Jose-Luis; Huxley, Peter

    2007-07-01

    In recent years, there has been significant concern, and policy activity, in relation to the problem of delayed discharges from hospital. Key elements of policy to tackle delays include new investment, the establishment of the Health and Social Care Change Agent Team, and the implementation of the Community Care (Delayed Discharge) Act 2003. Whilst the problem of delays has been widespread, some authorities have managed to tackle delays successfully. The aim of the qualitative study reported here was to investigate discharge practice and the organisation of services at sites with consistently low rates of delay, in order to identify factors supporting such good performance. Six 'high performing' English sites (each including a hospital trust, a local authority, and a primary care trust) were identified using a statistical model, and 42 interviews were undertaken with health and social services staff involved in discharge arrangements. Additionally, the authors set out to investigate the experiences of patients in the sites to examine whether there was a cost to patient care and outcomes of discharge arrangements in these sites, but unfortunately, it was not possible to secure sufficient patient participation. Whilst acknowledging the lack of patient experience and outcome data, a range of service elements was identified at the sites that contribute to the avoidance of delays, either through supporting efficiency within individual agencies or enabling more efficient joint working. Sites still struggling with delays should benefit from knowledge of this range. The government's reimbursement scheme appears to have been largely helpful in the study sites, prompting efficiency-driven changes to the organisation of services and discharge systems, but further focused research is required to provide clear evidence of its impact nationally, and in particular, how it impacts on staff, and patients and their families.

  11. High voltage high repetition rate pulse using Marx topology

    Science.gov (United States)

    Hakki, A.; Kashapov, N.

    2015-06-01

    The paper describes Marx topology using MOSFET transistors. Marx circuit with 10 stages has been done, to obtain pulses about 5.5KV amplitude, and the width of the pulses was about 30μsec with a high repetition rate (PPS > 100), Vdc = 535VDC is the input voltage for supplying the Marx circuit. Two Ferrite ring core transformers were used to control the MOSFET transistors of the Marx circuit (the first transformer to control the charging MOSFET transistors, the second transformer to control the discharging MOSFET transistors).

  12. Heart Rate at Hospital Discharge in Patients With Heart Failure Is Associated With Mortality and Rehospitalization

    Science.gov (United States)

    Laskey, Warren K.; Alomari, Ihab; Cox, Margueritte; Schulte, Phillip J.; Zhao, Xin; Hernandez, Adrian F.; Heidenreich, Paul A.; Eapen, Zubin J.; Yancy, Clyde; Bhatt, Deepak L.; Fonarow, Gregg C.

    2015-01-01

    Background Whether heart rate upon discharge following hospitalization for heart failure is associated with long‐term adverse outcomes and whether this association differs between patients with sinus rhythm (SR) and atrial fibrillation (AF) have not been well studied. Methods and Results We conducted a retrospective cohort study from clinical registry data linked to Medicare claims for 46 217 patients participating in Get With The Guidelines®–Heart Failure. Cox proportional‐hazards models were used to estimate the association between discharge heart rate and all‐cause mortality, all‐cause readmission, and the composite outcome of mortality/readmission through 1 year. For SR and AF patients with heart rate ≥75, the association between heart rate and mortality (expressed as hazard ratio [HR] per 10 beats‐per‐minute increment) was significant at 0 to 30 days (SR: HR 1.30, 95% CI 1.22 to 1.39; AF: HR 1.23, 95% CI 1.16 to 1.29) and 31 to 365 days (SR: HR 1.15, 95% CI 1.12 to 1.20; AF: HR 1.05, 95% CI 1.01 to 1.08). Similar associations between heart rate and all‐cause readmission and the composite outcome were obtained for SR and AF patients from 0 to 30 days but only in the composite outcome for SR patients over the longer term. The HR from 0 to 30 days exceeded that from 31 to 365 days for both SR and AF patients. At heart rates heart failure, higher discharge heart rate was associated with increased risks of death and rehospitalization, with higher risk in the first 30 days and for SR compared with AF. PMID:25904590

  13. Effect of Electric Discharge Machining on Material Removal Rate and White Layer Composition

    Directory of Open Access Journals (Sweden)

    SHAHID MEHMOOD

    2017-01-01

    Full Text Available In this study the MRR (Material Removal Rate of the aerospace grade (2024 T6 aluminum alloy 2024 T6 has been determined with copper electrode and kerosene oil is used as dielectric liquid. Discharge energy is controlled by electric current while keeping Pulse-ON time and Pulse-OFF time as constant. The characteristics of the EDMed (Electric Discharge Machined surface are discussed. The sub-surface defect due to arcing has been explained. As the surface material of tool electrode and workpiece melts simultaneously and there are chances of the contamination of both surfaces by the contents of each other. Therefore, the EDS (Energy Dispersive Spectroscopy of the white layer and base material of the workpiece was performed by SEM (Scanning Electron Microscope at the discharge currents of 3, 6 and 12 amperes. It was conformed that the contamination of the surface of the workpiece material occurred by carbon, copper and oxygen contents. The quantitative analysis of these contents with respect to the discharge current has been presented in this paper.

  14. Assessing modern rates of river sediment discharge to the ocean using satellite gravimetry

    Science.gov (United States)

    Mouyen, Maxime; Longuevergne, Laurent; Steer, Philippe; Crave, Alain; Lemoine, Jean-Michel; Save, Himanshu; Robin, Cécile

    2017-04-01

    Worldwide rivers annually export about 19 Gigatons of sediments to the ocean that mostly accumulate in the coastal zones and on the continental shelves. This sediment discharge testifies of the intensity of continental erosion and records changes in climate, tectonics and human activity. However, natural and instrumental uncertainties inherent to the in-situ measurements of sediment discharge prevent from conclusive estimates to better understand these linkages. Here we develop a new method, using the Gravity Recovery and Climate Experiment (GRACE) satellite data, to infer mass-integrative estimates of sediment discharge of large rivers to the ocean. GRACE satellite provides global gravity time series that have proven useful for quantifying mass transport, including continental water redistribution at the Earth surface (ice sheets and glaciers melting, groundwater storage variations) but has been seldom used for monitoring sediment mass transfers so far. Here we pair the analysis of regularized GRACE solutions at high spatial resolution corrected from all known contributions (hydrology, ocean, atmosphere) to a particle tracking model that predicts the location of the sediment sinks for 13 rivers with the highest sediments loads in the world. We find that the resulting GRACE-derived sediment discharges off the mouth of the Amazon, Ganges-Brahmaputra, Changjiang (Yangtze), Indus, Magdalena, Godavari and Mekong rivers are consistent with in-situ measurements. Our results suggest that the lack of time continuity and of global coverage in terrestrial sediment discharge measurements could be reduced by using GRACE, which provides global and continuous data since 2002. GRACE solutions are regularly improved and new satellite gravity missions are being prepared hence making our approach even more relevant in a near future. The accumulation of sediments over time will keep increasing the signal to noise ratio of the gravity time series, which will improve the precision of

  15. High readmission rates and mental distress after infective endocarditis

    DEFF Research Database (Denmark)

    Rasmussen, Trine Bernholdt; Zwisler, Ann-Dorthe; Thygesen, Lau Caspar

    2017-01-01

    BACKGROUND: Infective endocarditis (IE) is a severe disease requiring lengthy hospitalisation. Little is known about patients' recovery after IE. The aims of this study in IE patients were; (i) to describe mortality, readmission, self-reported health and rehabilitation up to 1year post-discharge,......-off score of 8. Almost half (47%) had not been offered cardiac rehabilitation (CR). CONCLUSIONS: After IE, mortality and readmission rates were high and self-reported physical and mental health poor. These findings call for changes in in-hospital and post-discharge management....... in a questionnaire survey (responders n=122). Responses were compared with those of a background reference population and a heart valve surgery population. Mortality and readmission data from registers 12months post-discharge were investigated. RESULTS: Patients discharged after treatment for IE had a mortality...

  16. High-energy molecular lasers self-controlled volume-discharge lasers and applications

    CERN Document Server

    Apollonov, V V

    2016-01-01

    This book displays the physics and design of high-power molecular lasers. The lasers described are self-controlled volume-discharge lasers. The book explains self-sustained discharge lasers, self-initiated discharge lasers and technical approaches to laser design. Important topics discussed are laser efficiency, laser beam quality and electric field homogeneity. The book contains many new innovative applications.

  17. Robotic CABG decreases 30-day complication rate, length of stay and acute care facility discharge rate compared to conventional surgery

    Science.gov (United States)

    Leyvi, Galina; Forest, Stephen; Srinivas, V. S.; Greenberg, Mark; Wang, Nan; Mais, Alec; Snyder, Max; DeRose, Joseph J.

    2015-01-01

    Summary Objective The objective of this study was to compare the short term outcomes of robotic with conventional on pump coronary artery bypass grafting (CABG). Methods The study population included 2091 consecutive patients who underwent either conventional or robotic CABG from January 2007 to March 2012. Pre-operative, intra-operative and 30-day post-operative variables were collected for each group. In order to compare the incidence of rapid recovery between conventional and robotic CABG, the surrogate variables of early discharge and discharge to home (versus rehabilitation or acute care facility) were evaluated. A multivariate logistic regression analysis was utilized. Results One hundred and fifty robotic and 1,619 conventional CABG cases were analyzed. Multivariate logistic regression analysis demonstrated that robotic surgery was a strong predictor of lower 30-day complications (OR = 0.24, p=0.005), short length of stay (OR 3.31, p < 0.001), and decreased need for an acute care facility (OR 0.55, p = 0.032). In the presence of complications (NY State Complication Composite), the robotic technique was not associated with a change in discharge status. Conclusions In this retrospective review robotic CABG was associated with a lower 30-day complication rate, a shorter length of stay and a lower incidence of acute care facility discharge than conventional on pump CABG. It may suggest a more rapid recovery to pre-operative status after robotic surgery: however, only a randomized prospective study could confirm the advantages of a robotic approach PMID:25238421

  18. Investigation of Ozone Yield of Air Fed Ozonizer by High Pressure Homogeneous Dielectric Barrier Discharge

    Science.gov (United States)

    2013-07-01

    around 2 ms and 12 ms in this figure, and during the discharge period, the current was continuous without any pulse . Once a discharge generated in...electron avalanches [10]. Fig. 1. High pressure ozone generator. (a) Top view (b) Side view Fig. 2. Barrier discharge device. Table 1... discharge N. Osawa P1 P, UY. Yoshioka UP2 P, R. Hanaoka P1 P 1 Center for Electric, Optic and Energy applications, Department of Electric and

  19. Nanosecond-timescale high-pressure gas discharge in a microwave pulse compressor

    Science.gov (United States)

    Shlapakovski, Anatoli; Beilin, Leonid; Krasik, Yakov

    2016-09-01

    The results of experimental and numerical studies of the microwave plasma discharge initiated by a nanosecond laser pulse are presented. The discharge is ignited in the pressurized gas filling the switch, which opens the charged resonant cavity, so that the accumulated microwave energy is rapidly released into a load. Fast-framing optical imaging showed that the plasma in the switch appears as filaments expanding along the RF electric field. The temporal evolution of the plasma density was derived from time-resolved spectroscopic measurements. With increasing microwave energy in the cavity, the plasma appears earlier in time after the laser beam enters the switch and its density rises more steeply reaching values which exceed 1016 cm-3 at a gas pressure of 2 .105 Pa. Numerical simulations were conducted using the gas conductivity model of plasma and representation of discharge origin by setting initial population of seed electrons treated by PIC algorithm. The results showed good agreement with the experiments and explained how the self-consistent dynamics of the plasma and RF fields determines the quality of microwave output pulses. In addition, the dynamics of the microwave energy absorption in the discharge plasma was studied. It was shown that at a high pressure, even with an unlimited rate of ionization, a significant portion of the stored energy, 20%, is lost. This work was partially supported by the BSF Grant No. 2012038.

  20. Bidirectional Flyback Converter with Multiple Series Connected Outputs for High Voltage Capacitive Charge and Discharge Applications

    DEFF Research Database (Denmark)

    Thummala, Prasanth; Schneider, Henrik; Zhang, Zhe

    2015-01-01

    V) in series with a high voltage blocking diode is added, in parallel with a high voltage freewheeling diode of a conventional flyback topology, to enable bidirectional operation. Experimental result from a digitally controlled bidirectional flyback converter shows that the discharge energy efficiency...... by lower voltage rating MOSFETs driven by a gate drive transformer. Simulation results to compare the operation of conventional and proposed converters are provided. The advantages of proposed implementation are improved energy efficiency and lower cost. Experimental results with two series connected...

  1. Physical Kinetics of Electrons in a High-Voltage Pulsed High-Pressure Discharge with Cylindrical Geometry

    Science.gov (United States)

    Kozhevnikov, V. Yu.; Kozyrev, A. V.; Semeniuk, N. S.

    2017-12-01

    Results of theoretical modeling of the phenomenon of a high-voltage discharge in nitrogen at atmospheric pressure are presented, based on a consistent kinetic theory of the electrons. A mathematical model of a nonstationary high-pressure discharge has been constructed for the first time, based on a description of the electron component from first principles. The physical kinetics of the electrons are described with the help of the Boltzmann kinematic equation for the electron distribution function over momenta with only ionization and elastic collisions taken into account. A detailed spatiotemporal picture of a nonstationary discharge with runaway electrons under conditions of coaxial geometry of the gas diode is presented. The model describes in a self-consistent way both the process of formation of the runaway electron flux in the discharge and the influence of this flux on the rate of ionization processes in the gas. Total energy spectra of the electron flux incident on the anode are calculated. The obtained parameters of the current pulse of the beam of fast electrons correlate well with the known experimental data.

  2. Assessment of Estimation Methods ForStage-Discharge Rating Curve in Rippled Bed Rivers

    Directory of Open Access Journals (Sweden)

    P. Maleki

    2016-02-01

    Full Text Available Introduction: Interactionbetweenwater flow characteristics andthe bed erodibilityplays an important role in sediment transport process. In order to reach stability, rivers with deposition or bottom erosion make a different bed form in the riverbed. One way to identify thebehavior of therivers is to study the structure and formation of bed forms within them. Ripples are the smallest of the bed forms. The longitudinal cross section of ripples are usually not symmetrical. The upstream face is long and has a gentle slope, and the downstream face is short and steep. The height of ripples is usually between 0.5 cm and 2 cm; the height ripple is not more than 5 cm. The wave lengths normally do not exceed 30cm, and they are usually within the range of 1 cm to 15 cm. Their occurrence is the result of the unstable viscous layer near the boundary. They can form in both shallow and deep water.With an increase of the flow velocity, the plan form of the ripples gradually develops form straight line to curves and then to a pattern like fish scales, symmetrical or unsymmetrical, as shown in Fig 1. Figure1-The patterndevelopment oftheripple Raudkivi (1966 was the first person that, the flow structure over ripples was investigated experimentally.Hethenestablishseveraldifferent conditionsonthemovingsandbedinanlaboratorychannelconsisted of a rectangular cross-section with base width of 70cm, wasable toform arow ofripples , he wassucceed toform arow ofripples.JafariMianaei and Keshavarzi(2008,studied the turbulentflow betweentwoartificialripples for investigate the change of kinetic energyandshearstress on overripples. The stage- discharge rating curve is one of the most important tools in the hydraulic studies. In alluvial rivers,bed rippled are formed and significantly affect the stage- discharge rating curve. In this research, the effects of two different type of ripples (parallel and flakeshape onthe hydraulic characteristicsof flow were experimentally studied

  3. Effect of Doppler-shifted photons on subnanosecond breakdown in high-voltage pulse discharge

    Energy Technology Data Exchange (ETDEWEB)

    Schweigert, I. V. [Institute of Theoretical and Applied Mechanics, Novosibirsk 630090 (Russian Federation); George Washington University, Washington D.C. 20052 (United States); Alexandrov, A. L. [Institute of Theoretical and Applied Mechanics, Novosibirsk 630090 (Russian Federation); Zakrevsky, Dm. E.; Bokhan, P. A. [A.V. Rzhanov Institute of Semiconductor Physics, Novosibirsk 630090 (Russian Federation)

    2016-06-08

    The experiments in high-voltage open discharge in helium [1, 2] showed a controlled current growth rate of 500 A/(cm{sup 2}ns) for an applied voltage of 20 kV and gas pressure of 6 Torr. A kinetic model of the subnanosecond breakdown is developed to analyze the mechanism of current growth, which takes into account the kinetics of electrons, ions, fast atoms and photons with a Doppler shift (DS). DS photons appear in discharge due to collisions of heavy particles. Using particle in cell simulations, we show a critical role of DS photons in the electron emission from the cathode during the breakdown. Our experimental and calculation results show a decrease of the breakdown time with increasing gas pressure from 3 Torr to 16 Torr.

  4. HPV DNA Positivity Rate and Evaluation of Cytopatological Results in Patients with Chronic Vaginal Discharge

    Directory of Open Access Journals (Sweden)

    Güler Ateşer

    2014-06-01

    Full Text Available Aim: There are new publications stating that chronic infection may facilitate dysplastic changes and persistence of human papillomavirus (HPV-DNA positivity. Frequency of this coincidence and cervical cytological and pathological examination results were investigated in patients with chronic vaginal discharge. Methods: One hundred three patients, who were treated at least 3 times for chronic mucopurulent discharge with accessible HPV DNA results, were analyzed retrospectively. Risk factors were identified for HPV DNA positivity. HPV DNA positive-patients were divided into two groups (positive and negative according to the presence and absence of HPV DNA. The results of cytopatological and histopathological examinations and risk factors were compared between the two groups. Results: The mean age of the patients was 35±9 years. Sixty-four percent of the patients were positive for HPV DNA. Of the HPV DNA positive patients, 41% had abnormal cytological findings, 16% had cervical intraepithelial neoplasia (CIN. Of the HPV DNA-negative patients, 16% had abnormal cytological findings and, 2 patients had CIN. There was no statistically significant difference in cervical cytological abnormalities and CIN between HPV-DNA positive and negative groups. Conclusion: In our study, the rates of HPV DNA positivity and abnormal cytopathological results among patients with chronic vaginal discharge were found to be higher than that reported in the literature. (The Me­di­cal Bul­le­tin of Ha­se­ki 2014; 52: 93-7

  5. Plutonium Discharge Rates and Spent Nuclear Fuel Inventory Estimates for Nuclear Reactors Worldwide

    Energy Technology Data Exchange (ETDEWEB)

    Brian K. Castle; Shauna A. Hoiland; Richard A. Rankin; James W. Sterbentz

    2012-09-01

    This report presents a preliminary survey and analysis of the five primary types of commercial nuclear power reactors currently in use around the world. Plutonium mass discharge rates from the reactors’ spent fuel at reload are estimated based on a simple methodology that is able to use limited reactor burnup and operational characteristics collected from a variety of public domain sources. Selected commercial reactor operating and nuclear core characteristics are also given for each reactor type. In addition to the worldwide commercial reactors survey, a materials test reactor survey was conducted to identify reactors of this type with a significant core power rating. Over 100 material or research reactors with a core power rating >1 MW fall into this category. Fuel characteristics and spent fuel inventories for these material test reactors are also provided herein.

  6. Breakdown in helium in high-voltage open discharge with subnanosecond current front rise

    Energy Technology Data Exchange (ETDEWEB)

    Schweigert, I. V., E-mail: ischweig@itam.nsc.ru; Alexandrov, A. L. [Russian Academy of Sciences, Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch (Russian Federation); Bokhan, P. A.; Zakrevskiy, Dm. E. [Russian Academy of Sciences, Rzhanov Institute of Semiconductors Physics, Siberian Branch (Russian Federation)

    2016-07-15

    Investigations of high-voltage open discharge in helium have shown a possibility of generation of current pulses with subnanosecond front rise, due to ultra-fast breakdown development. The open discharge is ignited between two planar cathodes with mesh anode in the middle between them. For gas pressure 6 Torr and 20 kV applied voltage, the rate of current rise reaches 500 A/(cm{sup 2} ns) for current density 200 A/cm{sup 2} and more. The time of breakdown development was measured for different helium pressures and a kinetic model of breakdown in open discharge is presented, based on elementary reactions for electrons, ions and fast atoms. The model also includes various cathode emission processes due to cathode bombardment by ions, fast atoms, electrons and photons of resonant radiation with Doppler shift of frequency. It is shown, that the dominating emission processes depend on the evolution of the discharge voltage during the breakdown. In the simulations, two cases of voltage behavior were considered: (i) the voltage is kept constant during the breakdown; (ii) the voltage is reduced with the growth of current. For the first case, the exponentially growing current is maintained due to photoemission by the resonant photons with Doppler-shifted frequency. For the second case, the dominating factor of current growth is the secondary electron emission. In both cases, the subnanosecond rise of discharge current was obtained. Also the effect of gas pressure on breakdown development was considered. It was found that for 20 Torr gas pressure the time of current rise decreases to 0.1 ns, which is in agreement with experimental data.

  7. AIR ATMOSPHERIC-PRESSURE DISCHARGERS FOR OPERATION IN HIGH-FREQUENCY SWITCHING MODE.

    Directory of Open Access Journals (Sweden)

    L.S. Yevdoshenko

    2013-10-01

    Full Text Available Operation of two designs of compact multigap dischargers has been investigated in a high-frequency switching mode. It is experimentally revealed that the rational length of single discharge gaps in the designs is 0.3 mm, and the maximum switching frequency is 27000 discharges per second under long-term stable operation of the dischargers. It is shown that in pulsed corona discharge reactors, the pulse front sharpening results in increasing the operating electric field strength by 1.3 – 1.8 times.

  8. Influence of expander components on the processes at the negative plates of lead-acid cells on high-rate partial-state-of-charge cycling. Part II. Effect of carbon additives on the processes of charge and discharge of negative plates

    Energy Technology Data Exchange (ETDEWEB)

    Pavlov, D.; Nikolov, P.; Rogachev, T. [Institute of Electrochemistry and Energy Systems, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Street, bl. 10, Sofia 1113 (Bulgaria)

    2010-07-15

    Lead-acid batteries operated in the high-rate partial-state-of-charge (HRPSoC) duty rapidly lose capacity on cycling, because of sulfation of the negative plates. As the battery operates from a partially discharged state, the small PbSO{sub 4} crystals dissolve and precipitate onto the bigger crystals. The latter have low solubility and hence PbSO{sub 4} accumulates progressively in the negative plates causing capacity loss. In order to suppress this process, the rate of the charge process should be increased. In a previous publication of ours we have established that reduction of Pb{sup 2+} ions to Pb may proceed on the surface of both Pb and carbon black particles. Hence, the reversibility of the charge-discharge processes improves, which leads to improved cycle life performance of the batteries in the HRPSoC mode. However, not all carbon forms accelerate the charge processes. The present paper discusses the electrochemical properties of two groups of carbon blacks: Printex and active carbons. The influence of Vaniseprse A and BaSO{sub 4} (the other two components of the expander added to the negative plates) on the reversibility of the charge-discharge processes on the negative plates is also considered. It has been established that lignosulfonates are adsorbed onto the lead surface and retard charging of the battery. BaSO{sub 4} has the opposite effect, which improves the reversibility of the processes on cycling and hence prolongs battery life in the HRPSoC duty. It has been established that the cycle life of lead-acid cells depends on the type of carbon black or active carbon added to the negative plates. When the carbon particles are of nano-sizes (<180 nm), the HRPSoC cycle life is between 10,000 and 20,000 cycles. Lignosulfonates suppress this beneficial effect of carbon black and activated carbon additives to about 10,000 cycles. Cells with active carbons have the longest cycle life when they contain also BaSO{sub 4} but no lignosulfonate. A summary of

  9. The fastest flights in nature: high-speed spore discharge mechanisms among fungi.

    Directory of Open Access Journals (Sweden)

    Levi Yafetto

    Full Text Available BACKGROUND: A variety of spore discharge processes have evolved among the fungi. Those with the longest ranges are powered by hydrostatic pressure and include "squirt guns" that are most common in the Ascomycota and Zygomycota. In these fungi, fluid-filled stalks that support single spores or spore-filled sporangia, or cells called asci that contain multiple spores, are pressurized by osmosis. Because spores are discharged at such high speeds, most of the information on launch processes from previous studies has been inferred from mathematical models and is subject to a number of errors. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we have used ultra-high-speed video cameras running at maximum frame rates of 250,000 fps to analyze the entire launch process in four species of fungi that grow on the dung of herbivores. For the first time we have direct measurements of launch speeds and empirical estimates of acceleration in these fungi. Launch speeds ranged from 2 to 25 m s(-1 and corresponding accelerations of 20,000 to 180,000 g propelled spores over distances of up to 2.5 meters. In addition, quantitative spectroscopic methods were used to identify the organic and inorganic osmolytes responsible for generating the turgor pressures that drive spore discharge. CONCLUSIONS/SIGNIFICANCE: The new video data allowed us to test different models for the effect of viscous drag and identify errors in the previous approaches to modeling spore motion. The spectroscopic data show that high speed spore discharge mechanisms in fungi are powered by the same levels of turgor pressure that are characteristic of fungal hyphae and do not require any special mechanisms of osmolyte accumulation.

  10. Impurity transport of high performance discharges in JET

    Energy Technology Data Exchange (ETDEWEB)

    Lauro-Taroni, L.; Alper, B.; Giannella, R.; Marcus, F.; Smeulders, P.; Von Hellermann, M. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Lawson, K. [UKAEA Culham Lab., Abingdon (United Kingdom); Mattioli, M. [Association Euratom-CEA, Centre d`Etudes Nucleaires de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee

    1994-07-01

    Experimental data show that in the Pellet Enhanced Performance (PEP) H-mode discharges, the light impurities are dominant and accumulate. Furthermore, strong fuel depletion may occur in the plasma centre with n{sub D}/n{sub e} falling to about 0.3 in some cases. On the other hand, in Hot-Ion discharges hollow profiles are measured for C: it is present in lower concentrations and has little effect on fuel dilution. The different behaviour of carbon in the two cases is in agreement with neoclassical predictions for the convection in the plasma core. 6 refs., 6 figs.

  11. High Resolution, High Frame Rate Video Technology

    Science.gov (United States)

    1990-01-01

    Papers and working group summaries presented at the High Resolution, High Frame Rate Video (HHV) Workshop are compiled. HHV system is intended for future use on the Space Shuttle and Space Station Freedom. The Workshop was held for the dual purpose of: (1) allowing potential scientific users to assess the utility of the proposed system for monitoring microgravity science experiments; and (2) letting technical experts from industry recommend improvements to the proposed near-term HHV system. The following topics are covered: (1) State of the art in the video system performance; (2) Development plan for the HHV system; (3) Advanced technology for image gathering, coding, and processing; (4) Data compression applied to HHV; (5) Data transmission networks; and (6) Results of the users' requirements survey conducted by NASA.

  12. Hospital Variation in Rates of New Institutionalizations Within 6 Months of Discharge.

    Science.gov (United States)

    Middleton, Addie; Zhou, Jie; Ottenbacher, Kenneth J; Goodwin, James S

    2017-06-01

    Hospitalization in community-dwelling elderly is often accompanied by functional loss, increasing the risk for continued functional decline and future institutionalization. The primary objective of our study was to examine the hospital-level variation in rates of new institutionalizations among Medicare beneficiaries. Retrospective cohort study. Hospitals and nursing homes. Medicare fee-for-service beneficiaries discharged from 4,469 hospitals in 2013 (N = 4,824,040). New institutionalization, defined as new long term care nursing home residence (not skilled nursing facility) of at least 90 days duration within 6 months of hospital discharge. The overall observed rate of new institutionalizations was 3.6% (N = 173,998). Older age, white race, Medicaid eligibility, longer hospitalization, and having a skilled nursing facility stay over the 6 months before hospitalization were associated with higher adjusted odds. Observed rates ranged from 0.9% to 5.9% across states. The variation in rates attributable to the hospital after adjusting for case-mix and state was 5.1%. Odds were higher for patients treated in smaller (OR = 1.36, 95% CI: 1.27-1.45, ≤50 vs >500 beds), government owned (OR = 1.15, 95% CI: 1.09-1.21 compared to for-profit), limited medical school affiliation (OR = 1.13, 95% CI: 1.07-1.19 compared to major) hospitals and lower for patients treated in urban hospitals (OR = 0.79, 95% CI: 0.76-0.82 compared to rural). Higher Summary Star ratings (OR = 0.75, 95% CI: 0.67-0.93, five vs one stars) and Overall Hospital Rating (OR = 0.62, 95% CI: 0.57-0.67, ratings of 9-10 vs 0) were associated with lower odds of institutionalization. Hospitalization may be a critical period for preventing future institutionalization among elderly patients. The variation in rates across hospitals and its association with hospital quality ratings suggest some of these institutionalizations are avoidable and may represent targets for care improvement. © 2017, Copyright the Authors

  13. Dynamic linear models to explore time-varying suspended sediment-discharge rating curves

    Science.gov (United States)

    Ahn, Kuk-Hyun; Yellen, Brian; Steinschneider, Scott

    2017-06-01

    This study presents a new method to examine long-term dynamics in sediment yield using time-varying sediment-discharge rating curves. Dynamic linear models (DLMs) are introduced as a time series filter that can assess how the relationship between streamflow and sediment concentration or load changes over time in response to a wide variety of natural and anthropogenic watershed disturbances or long-term changes. The filter operates by updating parameter values using a recursive Bayesian design that responds to 1 day-ahead forecast errors while also accounting for observational noise. The estimated time series of rating curve parameters can then be used to diagnose multiscale (daily-decadal) variability in sediment yield after accounting for fluctuations in streamflow. The technique is applied in a case study examining changes in turbidity load, a proxy for sediment load, in the Esopus Creek watershed, part of the New York City drinking water supply system. The results show that turbidity load exhibits a complex array of variability across time scales. The DLM highlights flood event-driven positive hysteresis, where turbidity load remained elevated for months after large flood events, as a major component of dynamic behavior in the rating curve relationship. The DLM also produces more accurate 1 day-ahead loading forecasts compared to other static and time-varying rating curve methods. The results suggest that DLMs provide a useful tool for diagnosing changes in sediment-discharge relationships over time and may help identify variability in sediment concentrations and loads that can be used to inform dynamic water quality management.

  14. ROSC rates and live discharge rates after cardiopulmonary resuscitation by different CPR teams - a retrospective cohort study.

    Science.gov (United States)

    Oh, Tak Kyu; Park, Young Mi; Do, Sang-Hwan; Hwang, Jung-Won; Song, In-Ae

    2017-12-04

    Previous studies have reported that the quality of cardiopulmonary resuscitation (CPR) is closely associated with patient outcomes. The aim of this study was to compare patient CPR outcomes across resident, emergency medicine, and rapid response teams. The records of patients who underwent CPR at the Seoul National University Bundang Hospital from January 1, 2013 to December 31, 2016 were analyzed retrospectively. Return of spontaneous circulation, 10- and 30-day survival, and live discharge after return of spontaneous circulation were compared across patients treated by the three CPR teams. Of the 1145 CPR cases, 444 (39%) were conducted by the resident team, 431 (38%) by the rapid response team, and 270 (23%) by the emergency medicine team. The adjusted odds ratios for the return of spontaneous circulation and subsequent 10-day survival among patients who received CPR from the resident team compared to the rapid response team were 0.59 (P = 0.001) and 0.71 (P = 0.037), respectively. There were no significant differences in the 30-day survival and rate of live discharge between patients who received CPR from the rapid response and resident teams; likewise, no significant differences were observed between patients who received CPR from the emergency medicine and rapid response teams. Patients receiving CPR from the rapid response team may have higher 10-day survival and return of spontaneous circulation rates than those who receive CPR from the resident team. However, our results are limited by the differences in approach, time of CPR, and room settings between teams.

  15. High-intensity xenon plasma discharge lamp for bulk-sensitive high-resolution photoemission spectroscopy.

    Science.gov (United States)

    Souma, S; Sato, T; Takahashi, T; Baltzer, P

    2007-12-01

    We have developed a highly brilliant xenon (Xe) discharge lamp operated by microwave-induced electron cyclotron resonance (ECR) for ultrahigh-resolution bulk-sensitive photoemission spectroscopy (PES). We observed at least eight strong radiation lines from neutral or singly ionized Xe atoms in the energy region of 8.4-10.7 eV. The photon flux of the strongest Xe I resonance line at 8.437 eV is comparable to that of the He Ialpha line (21.218 eV) from the He-ECR discharge lamp. Stable operation for more than 300 h is achieved by efficient air-cooling of a ceramic tube in the resonance cavity. The high bulk sensitivity and high-energy resolution of PES using the Xe lines are demonstrated for some typical materials.

  16. Association between the unemployment rate and inpatient cost per discharge by payer in the United States, 2005-2010.

    Science.gov (United States)

    Maeda, Jared Lane K; Henke, Rachel Mosher; Marder, William D; Karaca, Zeynal; Friedman, Bernard S; Wong, Herbert S

    2014-10-13

    Several reports have linked the 2007-2009 Great Recession in the United States with a slowdown in health care spending and decreased utilization. However, little is known regarding how the recent economic downturn affected hospital costs per inpatient stay for different segments of the population. The purpose of this study was to examine the association between changes in the unemployment rate and inpatient cost per discharge for Medicare and commercial discharges. We used retrospective data at the Core Based Statistical Area (CBSA)-level from 46 states that contributed to the Healthcare Cost and Utilization Project State Inpatient Databases from 2005 to 2010. Unemployment data was derived from the American Community Survey. An instrumental variable two-stage least squares approach with fixed- or random-effects was used to examine the association between unemployment rate and inpatient cost per discharge by payer because of potential endogeneity. The marginal effect of unemployment was associated with an increase in inpatient cost per discharge for both payers. A one percentage point increase in the unemployment rate was associated with a $37 increase for commercial discharges and a $49 increase for Medicare discharges. We find evidence that the inpatient cost per discharge is countercyclical across different segments of the population. The underlying mechanisms by which unemployment affects hospital resource use however, might differ between payer groups.

  17. Explosive Processes on Cathode while Forming Nanosecond Pulsed Discharge of High Pressure

    National Research Council Canada - National Science Library

    A. Hashimov; R. Mekhtizadeh; А. Bondyakov; Sh. Kazimov

    2012-01-01

    ...) while forming nanosecond pulsed discharge in dense air. Influence of field and air pressure heterogeneity rate in gas gap on size of micro-craters being formed on working cathode surface after pulsed effect has been shown in the paper...

  18. Max Tech and Beyond: High-Intensity Discharge Lamps

    Energy Technology Data Exchange (ETDEWEB)

    Scholand, Michael

    2012-04-01

    High-intensity discharge (HID) lamps are most often found in industrial and commercial applications, and are the light source of choice in street and area lighting, and sports stadium illumination. HID lamps are produced in three types - mercury vapor (MV), high pressure sodium (HPS) and metal halide (MH). Of these, MV and MH are considered white-light sources (although the MV exhibits poor color rendering) and HPS produces a yellow-orange color light. A fourth lamp, low-pressure sodium (LPS), is not a HID lamp by definition, but it is used in similar applications and thus is often grouped with HID lamps. With the notable exception of MV which is comparatively inefficient and in decline in the US from both a sales and installed stock point of view; HPS, LPS and MH all have efficacies over 100 lumens per watt. The figure below presents the efficacy trends over time for commercially available HID lamps and LPS, starting with MV and LPS in 1930's followed by the development of HPS and MH in the 1960's. In HID lamps, light is generated by creating an electric arc between two electrodes in an arc tube. The particles in the arc are partially ionized, making them electrically conductive, and a light-emitting 'plasma' is created. This arc occurs within the arc tube, which for most HID lamps is enclosed within an evacuated outer bulb that thermally isolates and protects the hot arc tube from the surroundings. Unlike a fluorescent lamp that produces visible light through down-converting UV light with phosphors, the arc itself is the light source in an HID lamp, emitting visible radiation that is characteristic of the elements present in the plasma. Thus, the mixture of elements included in the arc tube is one critical factor determining the quality of the light emitted from the lamp, including its correlated color temperature (CCT) and color rendering index (CRI). Similar to fluorescent lamps, HID lamps require a ballast to start and maintain stable

  19. Coordinated Secondary Control for Balanced Discharge Rate of Energy Storage System in Islanded AC Microgrids

    DEFF Research Database (Denmark)

    Guan, Yajuan; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2016-01-01

    A coordinated secondary control approach based on an autonomous current-sharing control strategy for balancing the discharge rates of energy storage systems (ESSs) in islanded AC microgrids is proposed in this paper. The coordinated secondary controller can regulate the power outputs of distributed...... generation (DG) units according to their states-of-charge (SoCs) and ESS capacities by adjusting the virtual resistances of the paralleled voltage-controlled inverters. Compared with existing controllers, the proposed control strategy not only effectively prevents operation failure caused by overcurrent...... incidents and unintentional outages in DG units, but also aims to provide a fast transient response and an accurate output-current-sharing performance. A complete root locus analysis is given in order to achieve system stability and parameter sensitivity. Experimental results are presented to show...

  20. Coordinated Secondary Control for Balanced Discharge Rate of Energy Storage System in Islanded Microgrids

    DEFF Research Database (Denmark)

    Guan, Yajuan; Guerrero, Josep M.; Quintero, Juan Carlos Vasquez

    2015-01-01

    current and unintentional outage of DGs. Thus, the stability and reliability of islanded MG can be improved. The eigenvalues and root locus with the proposed controller are presented to design the parameters as well as analyzing the system stability. Simulation results based on Matlab......A coordinated secondary control based on a novel autonomous currents sharing control strategy for balanced discharge rate of energy storage systems in islanded microgrid (MG) is proposed in this paper. The coordinated secondary controller is able to regulate the output power of distributed...... generating (DG) systems according to their state-of-charge by adjusting the virtual resistances of their voltage controlled inverters. This controller can not only provide the faster response and accurate output current sharing control, but also avoid the potential operation failure resulting from the over...

  1. Subnanosecond breakdown development in high-voltage pulse discharge: Effect of secondary electron emission

    Science.gov (United States)

    Alexandrov, A. L.; Schweigert, I. V.; Zakrevskiy, Dm. E.; Bokhan, P. A.; Gugin, P.; Lavrukhin, M.

    2017-10-01

    A subnanosecond breakdown in high-voltage pulse discharge may be a key tool for superfast commutation of high power devices. The breakdown in high-voltage open discharge at mid-high pressure in helium was studied in experiment and in kinetic simulations. The kinetic model of electron avalanche development was constructed, based on PIC-MCC simulations, including dynamics of electrons, ions and fast helium atoms, produced by ions scattering. Special attention was paid to electron emission processes from cathode, such as: photoemission by Doppler-shifted resonant photons, produced in excitation processes involving fast atoms; electron emission by ions and fast atoms bombardment of cathode; the secondary electron emission (SEE) by hot electrons from bulk plasma. The simulations show that the fast atoms accumulation is the main reason of emission growth at the early stage of breakdown, but at the final stage, when the voltage on plasma gap diminishes, namely the SEE is responsible for subnanosecond rate of current growth. It was shown that the characteristic time of the current growth can be controlled by the SEE yield. The influence of SEE yield for three types of cathode material (titanium, SiC, and CuAlMg-alloy) was tested. By changing the pulse voltage amplitude and gas pressure, the area of existence of subnanosecond breakdown is identified. It is shown that in discharge with SiC and CuAlMg-alloy cathodes (which have enhanced SEE) the current can increase with a subnanosecond characteristic time value as small as τs = 0.4 ns, for the pulse voltage amplitude of 5÷12 kV. An increase of gas pressure from 15 Torr to 30 Torr essentially decreases the time of of current front growth, whereas the pulse voltage variation weakly affects the results.

  2. A diagnostic system for electrical faults in a high current discharge plasma setup

    Energy Technology Data Exchange (ETDEWEB)

    Nigam, S.; Aneesh, K.; Navathe, C. P.; Gupta, P. D. [Raja Ramanna Centre for Advanced Technology, Indore 452013 (India)

    2011-02-15

    A diagnostic system to detect electrical faults inside a coaxial high current discharge device is presented here. This technique utilizes two biconical antennas picking up electromagnetic radiation from the discharge device, a voltage divider sensing input voltage, and a Rogowski coil measuring the main discharge current. A computer program then analyses frequency components in these signals and provides information as to whether the discharge event was normal or any breakdown fault occurred inside the coaxial device. The diagnostic system is developed for a 450 kV and 50 kA capillary discharge plasma setup. For the setup various possible faults are analyzed by electrical simulation, followed by experimental results. In the case of normal discharge through the capillary load the dominant frequency is {approx}4 MHz. Under faulty conditions, the peak in magnitude versus frequency plot of the antenna signal changes according to the fault position which involves different paths causing variation in the equivalent circuit elements.

  3. A diagnostic system for electrical faults in a high current discharge plasma setup.

    Science.gov (United States)

    Nigam, S; Aneesh, K; Navathe, C P; Gupta, P D

    2011-02-01

    A diagnostic system to detect electrical faults inside a coaxial high current discharge device is presented here. This technique utilizes two biconical antennas picking up electromagnetic radiation from the discharge device, a voltage divider sensing input voltage, and a Rogowski coil measuring the main discharge current. A computer program then analyses frequency components in these signals and provides information as to whether the discharge event was normal or any breakdown fault occurred inside the coaxial device. The diagnostic system is developed for a 450 kV and 50 kA capillary discharge plasma setup. For the setup various possible faults are analyzed by electrical simulation, followed by experimental results. In the case of normal discharge through the capillary load the dominant frequency is ∼4 MHz. Under faulty conditions, the peak in magnitude versus frequency plot of the antenna signal changes according to the fault position which involves different paths causing variation in the equivalent circuit elements.

  4. A diagnostic system for electrical faults in a high current discharge plasma setup

    Science.gov (United States)

    Nigam, S.; Aneesh, K.; Navathe, C. P.; Gupta, P. D.

    2011-02-01

    A diagnostic system to detect electrical faults inside a coaxial high current discharge device is presented here. This technique utilizes two biconical antennas picking up electromagnetic radiation from the discharge device, a voltage divider sensing input voltage, and a Rogowski coil measuring the main discharge current. A computer program then analyses frequency components in these signals and provides information as to whether the discharge event was normal or any breakdown fault occurred inside the coaxial device. The diagnostic system is developed for a 450 kV and 50 kA capillary discharge plasma setup. For the setup various possible faults are analyzed by electrical simulation, followed by experimental results. In the case of normal discharge through the capillary load the dominant frequency is ˜4 MHz. Under faulty conditions, the peak in magnitude versus frequency plot of the antenna signal changes according to the fault position which involves different paths causing variation in the equivalent circuit elements.

  5. High power neon seeded JET discharges: Experiments and simulations

    Directory of Open Access Journals (Sweden)

    G. Telesca

    2017-08-01

    Full Text Available A series of neon seeded JET ELMy H-mode pulses is considered from the modeling as well as from the experimental point of view. For two different Ne seeding rates and two different D puffing gas levels the heating power, Pheat, is in the range 22–29.5 MW. The main focus is on the numerical reconstruction of the total radiated power (which mostly depends on the W concentration and its distribution between core and divertor and of Zeff (which mostly depends on the Ne concentration. To model self-consistently the core and the SOL two input parameters had to be adjusted case by case: the SOL diffusivity, DSOL, and the core impurity inward pinch, vpinch. DSOL had to be increased with increasing ΓNe and the level of vpinch had to be changed, for any given ΓNe, according to the level of Pheat: it decreases with increasing Pheat. Since the ELM frequency, fELM, is experimentally correlated with Pheat, (it increases with Pheat the impurity inward pinch can be seen as to depend on fELM. Therefore, to maintain a low vpinch level (i.e. high fELM ΓNe/Pheat should not exceed a certain threshold, which slightly increases with the ΓD puffing rate. This might lead to a limitation in the viability of reducing the target heat load by Ne seeding at moderate ΓD, while keeping Zeff at acceptably low level.

  6. Suicide Risk Is High for Psychiatric Patients Long After Discharge from Care

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_166107.html Suicide Risk Is High for Psychiatric Patients Long After ... that psychiatric patients are at high risk for suicide immediately after being discharged from a mental health ...

  7. A 5 cm single-discharge CO2 laser having high power output

    NARCIS (Netherlands)

    Ernst, G.J.; Boer, A.G.

    1980-01-01

    A single-discharge self-sustained CO2 laser has been constructed with a gap distance of 5 cm. The system has a very simple construction; it produces a very uniform discharge with an output power of 50 Joules per liter for a CO2 : N2 : He = 1 : 1 : 3 mixture. The efficiency can be as high as 19%.

  8. Influence of expander components on the processes at the negative plates of lead-acid cells on high-rate partial-state-of-charge cycling. Part I: Effect of lignosulfonates and BaSO{sub 4} on the processes of charge and discharge of negative plates

    Energy Technology Data Exchange (ETDEWEB)

    Pavlov, D.; Nikolov, P.; Rogachev, T. [Institute of Electrochemistry and Energy Systems, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Street, bl. 10, Sofia 1113 (Bulgaria)

    2010-07-15

    This study investigates the influence of the organic expander component (Vanisperse A) and of BaSO{sub 4} on the performance of negative lead-acid battery plates on high-rate partial-state-of-charge (HRPSoC) cycling. Batteries operating in the HRPSoC mode should be classified as a separate type of lead-acid batteries. Hence, the additives to the negative plates should differ from the conventional expander composition. It has been established that lignosulfonates are adsorbed onto the lead surface and thus impede the charge processes, which results in impaired reversibility of the charge-discharge processes and hence shorter cycle life on HRPSoC operation, limited by sulfation of the negative plates. BaSO{sub 4} exerts the opposite effect: it improves the reversibility of the processes in the HRPSoC mode and hence prolongs the cycle life of the cells. The most pronounced effect of BaSO{sub 4} has been registered when it is added in concentration of 1.0 wt.% versus the leady oxide (LO) used for paste preparation. It has also been established that BaSO{sub 4} lowers the overpotential of PbSO{sub 4} nucleation. The results of the present investigation indicate that BaSO{sub 4} affects also the crystallization process of Pb during cell charging. Thus, BaSO{sub 4} eventually improves the performance characteristics of lead-acid cells on HRPSoC cycling. (author)

  9. Plasma decay in high-voltage nanosecond discharges in oxygen-containing mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Anokhin, E. M.; Popov, M. A. [Moscow Institute of Physics and Technology (Russian Federation); Kochetov, I. V. [Troitsk Institute for Innovation and Fusion Research (Russian Federation); Aleksandrov, N. L., E-mail: nick-aleksandrov@mail.ru [Moscow Institute of Physics and Technology (Russian Federation); Starikovskii, A. Yu. [Princeton University (United States)

    2016-01-15

    Plasma decay in high-voltage nanosecond discharges in CO{sub 2}: O{sub 2} and Ar: O{sub 2} mixtures at room gas temperature and a pressure of 10 Torr is studied experimentally and theoretically. The time dependence of the electron density during plasma decay is measured using microwave interferometry. The time evolution of the charged particle density, ion composition, and electron temperature is simulated numerically. It is shown that, under the given conditions, the discharge plasma is dominated for the most time by O{sub 2}{sup +} ions and plasma decay is determined by dissociative and three-body electron−ion recombination. As in the previous studies performed for air and oxygen plasmas, agreement between measurements and calculations is achieved only under the assumption that the rate of three-body recombination of molecular ions is much greater than that for atomic ions. The values of the rate constant of three-body recombination of electrons with O{sub 2}{sup +} ions in a wide range of electron temperatures (500–5500 K), as well as for thermal (300 K) electrons, are obtained by processing the experimental results.

  10. Remote sensing of stream flow rates - Correlation of meander and discharge spectra

    Science.gov (United States)

    Lingenfelter, R. E.; Schubert, G.

    1973-01-01

    Results of a study of river meander patterns and discharges, in which attempt was made to correlate the discharge spectrum of a river with the river meander power spectrum determined from aerial and satellite imagery. Some significant characteristics of both the discharge and the meander spectra have been discovered. Discharge frequency spectra based on long-term records of daily streamflow are found to have an inverse power-law dependence on discharge. This is shown to reflect the short-term decay of individual floods which are found to have an inverse power-law dependence on time. Meander power spectra for a number of river reaches, digitized from aerial photography, also show significant structure, the power spectral density having an inverse power-law dependence on wave number over one or more portions of the spectrum with breaks in the spectra at characteristic wave numbers. A number of examples of typical discharge and meander spectra are shown.

  11. A high-brightness repetitively pulsed UV radiation source using a linearly stabilized surface discharge

    Science.gov (United States)

    Bugrimov, S. N.; Kamrukov, A. S.; Kashnikov, G. N.; Kozlov, N. P.; Ovchinnikov, P. A.

    1986-01-01

    A method is proposed for initiating spark plasma discharges on a dielectric surface in the form of strictly rectilinear plasma channels. The method can be implemented using relatively modest (less than 25 kV) working and ignition voltages and does not require any 'hard' electrotechnical loops. Experiments were carried out in order to study the formation dynamics, energy, and spectral brightness characteristics of linearly stabilized surface discharges having linearly stabilized spark channel and the results are discussed. High-speed photographs of the discharges are presented and the spectrum of radiation from the discharges is illustrated in graphic form. It is shown that linearly stabilized discharges can be used to obtain high-power repetitively pulsed sources of CW ultraviolet radiation in the UV region having a brightness temperature of at least 40 K.

  12. Revisiting Project Re-Engineered Discharge (RED): The Impact of a Pharmacist Telephone Intervention on Hospital Readmission Rates.

    Science.gov (United States)

    Sanchez, Gail M; Douglass, Mark A; Mancuso, Michelle A

    2015-09-01

    Project Re-Engineered Discharge is a discharge nurse education (DNE) and pharmacist follow-up telephone intervention protocol that was shown to decrease rehospitalization significantly. The specific value of the pharmacist intervention was not originally evaluated. The objective of this study was to determine the impact of a pharmacist telephone intervention during the transition of care process on the rate of unplanned hospitalization within 30 days of patient discharge. A retrospective chart review was completed for patients who received DNE counseling and were discharged to home from the family medicine service at Boston Medical Center from July 2012 to May 2013. Patients were stratified into two groups: contacted/intervention and unable to contact/no intervention. The primary outcome was the rate of unplanned hospital utilization including emergency department visits and readmissions within 30 days of discharge. Secondary end points included number of pharmacist interventions and time spent on phone calls. A total of 401 patients were identified; 277 patients received a pharmacist telephone intervention, and 124 patients were unable to be contacted. Baseline characteristics did not differ between the two groups, with the exception of a higher prevalence of substance abuse in the nonintervention group (41.9% vs 21.3%, phospitalization (visits/patient) was significantly reduced in the intervention group, compared with the unable-to-contact group (0.227 vs 0.519, phospital discharge were more likely to be readmitted or visit the emergency department in the 30 days following discharge. A pharmacist telephone intervention as part of a comprehensive discharge protocol can have a positive impact on patients during the transition of care process by reducing incidence of unplanned hospital utilization. © 2015 Pharmacotherapy Publications, Inc.

  13. Impacts of a high-discharge submarine sewage outfall on water quality in the coastal zone of Salvador (Bahia, Brazil)

    KAUST Repository

    Roth, Florian

    2016-03-30

    Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine sewage outfall close to Salvador, Brazil. Impacts of untreated sewage discharge were evident at the outfall site by depleted δ13Corg and δ15N signatures and 4-fold increased BOD rates. Pollution effects of a sewage plume were detectable for more than 6 km downstream from the outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality.

  14. Improved high-intensity microwave discharge lamp for atomic resonance absorption and fluorescence spectrometry.

    Science.gov (United States)

    Lifshitz, A; Skinner, G B; Wood, D R

    1978-09-01

    An unusually good combination of high intensity and narrow line has been achieved in a microwave discharge lamp by placing the optical window in the center of the microwave cavity. Construction details and performance characteristics are described.

  15. Autism's 'Worryingly' High Suicide Rates Spur Conference

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_165946.html Autism's 'Worryingly' High Suicide Rates Spur Conference Signs of ... News) -- High rates of suicide among people with autism are drawing specialists to a conference this week ...

  16. Gas flow rate dependence of the discharge characteristics of a helium atmospheric pressure plasma jet interacting with a substrate

    Science.gov (United States)

    Yan, Wen; Economou, Demetre J.

    2017-10-01

    A 2D (axisymmetric) computational study of the discharge characteristics of an atmospheric pressure plasma jet as a function of gas flow rate was performed. The helium jet emerged from a dielectric tube, with an average gas flow velocity in the range 2.5-20 m s-1 (1 atm, 300 K) in a nitrogen ambient, and impinged on a substrate a short distance dowstream. The effect of the substrate conductivity (conductror versus insulator) was also studied. Whenever possible, simulation predictions were compared with published experimental observations. Discharge ignition and propagation in the dielectric tube were hardly affected by the He gas flow velocity. Most properties of the plasma jet, however, depended sensitively on the He gas flow velocity, which determined the concentration distributions of helium and nitrogen in the mixing layer forming in the gap between the tube exit and the substrate. At low gas flow velocity, the plasma jet evolved from a hollow (donut-shaped) feature to one where the maximum of electron density was on axis. When the gas flow velocity was high, the plasma jet maintained its hollow structure until it struck the substrate. For a conductive substrate, the radial ion fluxes to the surface were relatively uniform over a radius of ~0.4-0.8 mm, and the dominant ion flux was that of He+. For a dielectric substrate, the radial ion fluxes to the surface peaked on the symmetry axis at low He gas flow velocity, but a hollow ion flux distribution was observed at high gas flow velocity. At the same time, the main ion flux switched from N2+ to He2+ as the He gas flow velocity increased from a low to a high value. The diameter of the plasma ‘footprint’ on the substrate first increased with increasing He gas flow velocity, and eventually saturated with further increases in velocity.

  17. Miniaturized Stretchable and High-Rate Linear Supercapacitors

    Science.gov (United States)

    Zhu, Wenjun; Zhang, Yang; Zhou, Xiaoshuang; Xu, Jiang; Liu, Zunfeng; Yuan, Ningyi; Ding, Jianning

    2017-07-01

    Linear stretchable supercapacitors have attracted much attention because they are well suited to applications in the rapidly expanding field of wearable electronics. However, poor conductivity of the electrode material, which limits the transfer of electrons in the axial direction of the linear supercapacitors, leads to a serious loss of capacity at high rates. To solve this problem, we use gold nanoparticles to decorate aligned multiwall carbon nanotube to fabricate stretchable linear electrodes. Furthermore, we have developed fine stretchable linear supercapacitors, which exhibited an extremely high elasticity up to 400% strain with a high capacitance of about 8.7 F g-1 at the discharge current of 1 A g-1.

  18. High bit rate BPSK receiver

    Science.gov (United States)

    Osorio-Marti, J. A.; Sieiro, J. J.; Lopez-Villegas, J. M.

    2005-06-01

    This work presents a simple differentially BPSK receiver front-end using a novel schema without the need of an explicit carrier recovery system. The main principle of operation is the conversion of the incoming BPSK signal into an ASK signal having the same modulation pattern. Two versions of the system have been designed. One is intended to work at the 433.92 MHz ISM band and the other at 2 GHz frequency band. Accordingly, two prototypes of the system core, the BPSK to ASK converter circuit, have been implemented and tested. First a hybrid version for the low frequency operation and, second a multi chip module (MCM) for the 2 GHz frequency band. The system performance has been evaluated using Agilent Technologies Advanced Design System (ADS) platform. The ability to jointly perform system, circuit and EM simulations and co-simulations is the main advantage of this design tool. Obtained results indicate that modulation rates up to 20 Mbits/s for the hybrid version and up to 80 Mbits/s for the MCM version can be reached.

  19. The use of surface corona discharges to excite high-pressure gas-lasers

    Directory of Open Access Journals (Sweden)

    D. J. Brink

    1982-03-01

    Full Text Available A stabilization technique for the production of homogeneous gas discharge at high pressures has been developed. The technique is based on photo-pre-ionization from a corona-type surface-discharge. It was possible to develop a number of laser systems based on this stabilization principle, which exceeded the performance of conventional systems in many respects. This paper provides a summary of the most important properties and principles of the surface discharges. Four laser systems utilizing this stabilization method are also discussed.

  20. Discharge rate balancing control strategy based on dynamic consensus algorithm for energy storage units in AC microgrids

    DEFF Research Database (Denmark)

    Guan, Yajuan; Meng, Lexuan; Li, Chendan

    2017-01-01

    A dynamic consensus algorithm-based coordinated secondary control with an autonomous current-sharing control strategy is proposed in this paper for balancing discharge rate of energy storage systems (ESSs) in an islanded AC microgrid. The dynamic consensus algorithm is applied for information sha...

  1. Production of High Energy Ions Near an Ion Thruster Discharge Hollow Cathode

    Science.gov (United States)

    Katz, Ira; Mikellides, I. G.; Goebel, D. M.; Jameson, K. K.; Wirz, R.; Polk, James E.

    2006-01-01

    Several researchers have measured ions leaving ion thruster discharge chambers with energies far greater than measured discharge chamber potentials. Presented in this paper is a new mechanism for the generation of high energy ions and a comparison with measured ion spectra. The source of high energy ions has been a puzzle because they not only have energies in excess of measured steady state potentials, but as reported by Goebel et. al. [1], their flux is independent of the amplitude of time dependent plasma fluctuations. The mechanism relies on the charge exchange neutralization of xenon ions accelerated radially into the potential trough in front of the discharge cathode. Previous researchers [2] have identified the importance of charge exchange in this region as a mechanism for protecting discharge cathode surfaces from ion bombardment. This paper is the first to identify how charge exchange in this region can lead to ion energy enhancement.

  2. High-Resolution Discharge Forecasting for Snowmelt and Rainfall Mixed Events

    Directory of Open Access Journals (Sweden)

    Tomasz Berezowski

    2018-01-01

    Full Text Available Discharge events induced by mixture of snowmelt and rainfall are strongly nonlinear due to consequences of rain-on-snow phenomena and snowmelt dependence on energy balance. However, they received relatively little attention, especially in high-resolution discharge forecasting. In this study, we use Random Forests models for 24 h discharge forecasting in 1 h resolution in a 105.9 km 2 urbanized catchment in NE Poland: Biala River. The forcing data are delivered by Weather Research and Forecasting (WRF model in 1 h temporal and 4 × 4 km spatial resolutions. The discharge forecasting models are set in two scenarios with snowmelt and rainfall and rainfall only predictors in order to highlight the effect of snowmelt on the results (both scenarios use also pre-forecast discharge based predictors. We show that inclusion of snowmelt decrease the forecast errors for longer forecasts’ lead times. Moreover, importance of discharge based predictors is higher in the rainfall only models then in the snowmelt and rainfall models. We conclude that the role of snowmelt for discharge forecasting in mixed snowmelt and rainfall environments is in accounting for nonlinear physical processes, such as initial wetting and rain on snow, which cannot be properly modelled by rainfall only.

  3. High Glasgow Blatchford Score at admission is associated with recurrent bleeding after discharge for patients hospitalized with upper gastrointestinal bleeding.

    Science.gov (United States)

    Sengupta, Neil; Tapper, Elliot B; Patwardhan, Vilas R; Ketwaroo, Gyanprakash A; Thaker, Adarsh M; Leffler, Daniel A; Feuerstein, Joseph D

    2016-01-01

    Upper gastrointestinal bleeding (UGIB) is associated with significant morbidity. The Glasgow Blatchford Score (GBS) can predict endoscopic intervention and in-hospital death, but the ability to predict post-discharge outcomes is unknown. The aims of the study were to determine whether the admission GBS is associated with post-discharge rebleeding and 30-day readmission following hospitalization for UGIB. In this prospective, observational, cohort study, consecutive patients who were hospitalized with UGIB were enrolled. Admission GBS scores were calculated, and patients with GBS > 7 were classified as high risk. Patients were contacted 30 days following discharge to determine: 1) rate of hospital readmission due to rebleeding, 2) all-cause readmissions, and 3) mortality. Multivariable Cox regression was used to determine associations between GBS, rebleeding, and readmission. A total of 336 patients with UGIB were identified. Patients with high risk GBS were older (68 vs. 62 years; P = 0.01), and were more likely to receive blood (85 % vs. 39 %; P  7) should be monitored following discharge as they have a high risk of rebleeding. © Georg Thieme Verlag KG Stuttgart · New York.

  4. Rates of fuel discharge as affected by the design of fuel-injection systems for internal-combustion engines

    Science.gov (United States)

    Gelalles, A G; Marsh, E T

    1933-01-01

    Using the method of weighing fuel collected in a receiver during a definite interval of the injection period, rates of discharge were determined, and the effects noted, when various changes were made in a fuel-injection system. The injection system consisted primarily of a by-pass controlled fuel pump and an automatic injection valve. The variables of the system studied were the pump speed, pump-throttle setting, discharge-orifice diameter, injection-valve opening and closing pressures, and injection-tube length and diameter.

  5. High current 66 kV tests on high stability PFN discharge capacitors for CERN LHC

    CERN Document Server

    Barnes, M J

    1999-01-01

    The European Laboratory for Particle Physics (CERN) is constructing a Large Hadron Collider (LHC) to be installed in an existing 27 km circumference tunnel. The LHC will be equipped with fast pulsed magnet systems for injecting two counter-rotating hadron beams. Two pulsed systems, of 4 magnets and 4 pulse forming networks (PFNs) each, are required for this purpose. TRIUMF will build and test 5 resonant charging power supplies (RCPS) and nine PFNs and the associated thyratron switch units as part of the Canadian contribution to CERN LHC. Failures in the PFN capacitors may lead to incorrect beam deflections that may in turn damage LHC components. For this reason the reliability of the capacitors must be exceptionally high. Hence sample PFN capacitors were purchased and tested. The test procedure included discharging the PFN capacitors from 66 kV, into a 10.1 Ohm resistance, for 500,000 cycles, at a frequency of approximately 1 Hz. Subsequently the PFN capacitors were discharged from 66 kV into a 2.7 Ohm resist...

  6. High Risk Human Papilloma Virus Genotypes in Kurdistan Region in Patients with Vaginal Discharge.

    Science.gov (United States)

    Hussein, Nawfal R; Balatay, Amer A; Assafi, Mahde S; AlMufty, Tamara Abdulezel

    2016-01-01

    The human papilloma virus (HPV) is considered as the major risk factor for the development of cervical cancer. This virus is of different genotypes and generally can be classified into high and low risk types. To determine the rate of high risk HPV genotypes in women with vaginal discharge and lower abdominal pain in Kurdistan region, Iraq. Cervical swabs were taken from 104 women. DNA was extracted and the polymerase chain reaction (PCR) technique was used to determine the presence of high risk genotypes. It was found that 13/104 (12.5%) of the samples were positive for high risk HPV genotypes. Amongst those who were positive, 4/13 (30.7%) were typed as genotype 16 and 7/13 (53.8%) showed mixed genotyping. On the other hand, genotypes 53 and 56 were found in only one sample each. High risk HPV genotypes are not uncommon and further community based study is needed to determine the prevalence of HPV and its genotypes and plan for prevention of infection.

  7. Drift waves in a high-density cylindrical helicon discharge

    DEFF Research Database (Denmark)

    Schröder, C.; Grulke, O.; Klinger, T.

    2005-01-01

    of the background plasma parameters. All experimentally observed features of the instability are found to be consistent with drift waves. A linear nonlocal numerical model for drift modes, based on the two-fluid description of a plasma, is used for comparison between the experimental observations and theory....... Comparing numerical and experimental frequencies, it is found that the experimentally observed frequencies are consistent with drift waves. The numerical results show that the high electron collision frequencies provide the strongest destabilization mechanism in the helicon plasma. (c) 2005 American......A low-frequency instability. is investigated in a helicon plasma, which is characterized by comparably high plasma-beta and high collision frequencies. Single movable Langmuir probes and a poloidal probe. array are used for studies of spatiotemporal dynamics and for characterization...

  8. A Survey of Sinuous Ridges and Inferred Fluvial Discharge Rates in Northwest Hellas, Mars

    Science.gov (United States)

    Anderson, R. B.; Herkenhoff, K. E.

    2012-12-01

    Sinuous ridges are a widespread class of geomorphic feature on Mars, and in many cases are interpreted to be inverted fluvial channels. Although negative-relief valley networks thought to be related to fluvial activity have been mapped in detail over the entire planet (e.g. Carr, 1995; Hynek et al., 2010), few regional- to global-scale surveys of sinuous ridges have been conducted (e.g. Williams, 2007; Jacobsen and Burr, 2012). With the availability of Context Camera (CTX ) images from the Mars Reconnaissance Orbiter (MRO) covering a significant fraction of the martian surface at 6 meters per pixel, such studies are now feasible. In addition, Williams et al. (2009) have demonstrated that paleodischarge can be calculated based on the width, meander wavelength, and meander radius of sinuous ridges interpreted to be inverted channels. This method has been used successfully on the sinuous ridges in the Aeolis/Zephyria plana region (Burr et al., 2010). We have begun a survey of sinuous ridges in the northwest Hellas region (-15 N to -45 N, 30 E to 75 E) using 1156 radiometrically calibrated and map projected CTX images. This region includes the northwestern portion of the Hellas basin floor and rim, as well as a significant expanse of the cratered highlands to the north and west of the basin. This region was chosen because it includes terrain of varying age (primarily Noachian to Hesperian; Leonard and Tanaka, 2001) and includes "raised curvilinear features" identified by Williams (2007) on the western basin floor, northern rim, and in the highlands northwest of Hellas . By mapping the distribution of sinuous ridges in terrain of varying age and estimating their paleodischarge rates, we will be able to determine how the discharge rate varied over martian history. Carr, M. H. (1995), J. Geophys. Res., 100, 7479-7507, doi:10.1029/95JE00260. Hynek, B. M., M. Beach, and M. R. T. Hoke (2010), J. Geophys. Res., 115, E09008, doi:10.1029/2009JE003548. Williams, R.M.E. (2007

  9. High-efficiency dielectric barrier Xe discharge lamp: theoretical and experimental investigations

    Energy Technology Data Exchange (ETDEWEB)

    Beleznai, Sz [Department of Atomic Physics, Budapest University of Technology and Economics, 3-9 Muegyetem rkp., Budapest H-1111 (Hungary); Mihajlik, G [Department of Atomic Physics, Budapest University of Technology and Economics, 3-9 Muegyetem rkp., Budapest H-1111 (Hungary); Agod, A [GE Consumer and Industrial-Lighting, 77 Vaci ut, Budapest H-1344 (Hungary); Maros, I [GE Consumer and Industrial-Lighting, 77 Vaci ut, Budapest H-1344 (Hungary); Juhasz, R [GE Consumer and Industrial-Lighting, 77 Vaci ut, Budapest H-1344 (Hungary); Nemeth, Zs [GE Consumer and Industrial-Lighting, 77 Vaci ut, Budapest H-1344 (Hungary); Jakab, L [Department of Atomic Physics, Budapest University of Technology and Economics, 3-9 Muegyetem rkp., Budapest H-1111 (Hungary); Richter, P [Department of Atomic Physics, Budapest University of Technology and Economics, 3-9 Muegyetem rkp., Budapest H-1111 (Hungary)

    2006-09-07

    A dielectric barrier Xe discharge lamp producing vacuum-ultraviolet radiation with high efficiency was investigated theoretically and experimentally. The cylindrical glass body of the lamp is equipped with thin strips of metal electrodes applied to diametrically opposite sides of the outer surface. We performed a simulation of discharge plasma properties based on one-dimensional fluid dynamics and also assessed the lamp characteristics experimentally. Simulation and experimental results are analysed and compared in terms of voltage and current characteristics, power input and discharge efficiency. Using the proposed lamp geometry and fast rise-time short square pulses of the driving voltage, an intrinsic discharge efficiency around 56% was predicted by simulation, and more than 60 lm W{sup -1} lamp efficacy (for radiation converted into visible green light by phosphor coating) was demonstrated experimentally.

  10. Kinetics of charged particles in a high-voltage gas discharge in a nonuniform electrostatic field

    Energy Technology Data Exchange (ETDEWEB)

    Kolpakov, V. A., E-mail: kolpakov683@gmail.com; Krichevskii, S. V.; Markushin, M. A. [Korolev Samara National Research University (Russian Federation)

    2017-01-15

    A high-voltage gas discharge is of interest as a possible means of generating directed flows of low-temperature plasma in the off-electrode space distinguished by its original features [1–4]. We propose a model for calculating the trajectories of charges particles in a high-voltage gas discharge in nitrogen at a pressure of 0.15 Torr existing in a nonuniform electrostatic field and the strength of this field. Based on the results of our calculations, we supplement and refine the extensive experimental data concerning the investigation of such a discharge published in [1, 2, 5–8]; good agreement between the theory and experiment has been achieved. The discharge burning is initiated and maintained through bulk electron-impact ionization and ion–electron emission. We have determined the sizes of the cathode surface regions responsible for these processes, including the sizes of the axial zone involved in the discharge generation. The main effect determining the kinetics of charged particles consists in a sharp decrease in the strength of the field under consideration outside the interelectrode space, which allows a free motion of charges with specific energies and trajectories to be generated in it. The simulation results confirm that complex electrode systems that allow directed plasma flows to be generated at a discharge current of hundreds or thousands of milliamperes and a voltage on the electrodes of 0.3–1 kV can be implemented in practice [3, 9, 10].

  11. High-intensity discharge lamp and Duffing oscillator—Similarities and differences

    Science.gov (United States)

    Baumann, Bernd; Schwieger, Joerg; Stein, Ulrich; Hallerberg, Sarah; Wolff, Marcus

    2017-12-01

    The processes inside the arc tube of high-intensity discharge lamps are investigated using finite element simulations. The behavior of the gas mixture inside the arc tube is governed by differential equations describing mass, energy, and charge conservation, as well as the Helmholtz equation for the acoustic pressure and the Reynolds equations for the flow driven by buoyancy and Reynolds stresses. The model is highly nonlinear and requires a recursion procedure to account for the impact of acoustic streaming on the temperature and other fields. The investigations reveal the presence of a hysteresis and the corresponding jump phenomenon, quite similar to a Duffing oscillator. The similarities and, in particular, the differences of the nonlinear behavior of the high-intensity discharge lamp to that of a Duffing oscillator are discussed. For large amplitudes, the high-intensity discharge lamp exhibits a stiffening effect in contrast to the Duffing oscillator. It is speculated on how the stiffening might affect hysteresis suppression.

  12. 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.

  13. High-Efficiency Hall Thruster Discharge Power Converter

    Science.gov (United States)

    Jaquish, Thomas

    2015-01-01

    Busek Company, Inc., is designing, building, and testing a new printed circuit board converter. The new converter consists of two series or parallel boards (slices) intended to power a high-voltage Hall accelerator (HiVHAC) thruster or other similarly sized electric propulsion devices. The converter accepts 80- to 160-V input and generates 200- to 700-V isolated output while delivering continually adjustable 300-W to 3.5-kW power. Busek built and demonstrated one board that achieved nearly 94 percent efficiency the first time it was turned on, with projected efficiency exceeding 97 percent following timing software optimization. The board has a projected specific mass of 1.2 kg/kW, achieved through high-frequency switching. In Phase II, Busek optimized to exceed 97 percent efficiency and built a second prototype in a form factor more appropriate for flight. This converter then was integrated with a set of upgraded existing boards for powering magnets and the cathode. The program culminated with integrating the entire power processing unit and testing it on a Busek thruster and on NASA's HiVHAC thruster.

  14. Internal resistance of plastic bonded (pressed type) high rate Ni electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Kulcsar, S.; Horvath P.; Csath, G.; Smaroglay, M.

    1982-07-01

    Internal resistance is one of the most important characteristics of Ni-Cd cells. It has a great effect on the discharge voltage, capacity, and high rate behaviour. In this paper we report the results of an investigation in connection with the internal resistance of the plastic bonded Ni electrode and its variation as a function of pressure and high rate cycling.

  15. Discharge Physics of High Power Impulse Magnetron Sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Anders, Andre

    2010-10-13

    High power impulse magnetron sputtering (HIPIMS) is pulsed sputtering where the peak power exceeds the time-averaged power by typically two orders of magnitude. The peak power density, averaged over the target area, can reach or exceed 107 W/m2, leading to plasma conditions that make ionization of the sputtered atoms very likely. A brief review of HIPIMS operation is given in a tutorial manner, illustrated by some original data related to the self-sputtering of niobium in argon and krypton. Emphasis is put on the current-voltage-time relationships near the threshold of self-sputtering runaway. The great variety of current pulse shapes delivers clues on the very strong gas rarefaction, self-sputtering runaway conditions, and the stopping of runaway due to the evolution of atom ionization and ion return probabilities as the gas plasma is replaced by metal plasma. The discussions are completed by considering instabilities and the special case of ?gasless? self-sputtering.

  16. An asymmetric Zn//Ag doped polyaniline microparticle suspension flow battery with high discharge capacity

    Science.gov (United States)

    Wu, Sen; Zhao, Yongfu; Li, Degeng; Xia, Yang; Si, Shihui

    2015-02-01

    In this study, the effect of oxygen on the potential of reduced polyaniline (PANI) was investigated. In order to enhance the air oxidation of reduced PANI, several composites of PANI doped with co-catalysts were prepared, and a reasonable flow Zn//PANI suspension cell system was designed to investigate the discharge capacity of obtained PANI composite microparticle suspension cathodes. Compared with PANI doped with Cu2+, La+, Mn2+ and zinc protoporphyrin, Ag doped PANI composite at 0.90 weight percent doping of Ag gave the highest value of discharge capacity for the half-cell potential from the initial value to -0.20 V (vs. SCE). A comparison study on the electrochemical properties of both PANI and Ag doped PANI microparticle suspension was done by using cyclic voltammetry, AC Impedance. Due to partial utilization of Zn//air fuel cell, the discharge capacity for Ag doped PANI reached 470 mA h g-1 at the current density of 20 mA cm-2. At 15 mA cm-2, the discharge capacity even reached up to 1650 mA h g-1 after 220 h constant current discharge at the final discharge voltage of 0.65 V. This work demonstrates an effective and feasible approach toward obtaining high energy and power densities by a Zn//Ag-doped PANI suspension flow battery system combined with Zn//air fuel cell.

  17. Numerical Simulation of Non-Equilibrium Plasma Discharge for High Speed Flow Control

    Science.gov (United States)

    Balasubramanian, Ramakrishnan; Anandhanarayanan, Karupannasamy; Krishnamurthy, Rajah; Chakraborty, Debasis

    2017-06-01

    Numerical simulation of hypersonic flow control using plasma discharge technique is carried out using an in-house developed code CERANS-TCNEQ. The study is aimed at demonstrating a proof of concept futuristic aerodynamic flow control device. The Kashiwa Hypersonic and High Temperature wind tunnel study of plasma discharge over a flat plate had been considered for numerical investigation. The 7-species, 18-reaction thermo-chemical non-equilibrium, two-temperature air-chemistry model due Park is used to model the weakly ionized flow. Plasma discharge is modeled as Joule heating source terms in both the translation-rotational and vibrational energy equations. Comparison of results for plasma discharge at Mach 7 over a flat plate with the reference data reveals that the present study is able to mimic the exact physics of complex flow such as formation of oblique shock wave ahead of the plasma discharge region with a resultant rise in surface pressure and vibrational temperature up to 7000 K demonstrating the use of non-equilibrium plasma discharge for flow control at hypersonic speeds.

  18. Stereotactic radiosurgery - discharge

    Science.gov (United States)

    ... discharge; Linear accelerator - discharge; Lineacs - discharge; Proton beam radiosurgery - discharge ... You received stereotactic radiosurgery (SRS), or radiotherapy. This is a form of radiation therapy that focuses high-powered x-rays onto a small ...

  19. Plasma Perturbations in High-Speed Probing of Hall Thruster Discharge Chambers: Quantification and Mitigation

    Science.gov (United States)

    Jorns, Benjamin A.; Goebel, Dan M.; Hofer, Richard R.

    2015-01-01

    An experimental investigation is presented to quantify the effect of high-speed probing on the plasma parameters inside the discharge chamber of a 6-kW Hall thruster. Understanding the nature of these perturbations is of significant interest given the importance of accurate plasma measurements for characterizing thruster operation. An array of diagnostics including a high-speed camera and embedded wall probes is employed to examine in real time the changes in electron temperature and plasma potential induced by inserting a high-speed reciprocating Langmuir probe into the discharge chamber. It is found that the perturbations onset when the scanning probe is downstream of the electron temperature peak, and that along channel centerline, the perturbations are best characterized as a downstream shift of plasma parameters by 15-20% the length of the discharge chamber. A parametric study is performed to investigate techniques to mitigate the observed probe perturbations including varying probe speed, probe location, and operating conditions. It is found that the perturbations largely disappear when the thruster is operated at low power and low discharge voltage. The results of this mitigation study are discussed in the context of recommended methods for generating unperturbed measurements of the discharge chamber plasma.

  20. Variation in rates of ICU readmissions and post-ICU in-hospital mortality and their association with ICU discharge practices

    OpenAIRE

    Sluisveld, N. van; F. Bakhshi-Raiez; de Keizer, N; Holman, R.; Westert, G.P.; Wollersheim, H.C.; van der Hoeven, J. G.; Zegers, M.

    2017-01-01

    Background Variation in intensive care unit (ICU) readmissions and in-hospital mortality after ICU discharge may indicate potential for improvement and could be explained by ICU discharge practices. Our objective was threefold: (1) describe variation in rates of ICU readmissions within 48?h and post-ICU in-hospital mortality, (2) describe ICU discharge practices in Dutch hospitals, and (3) study the association between rates of ICU readmissions within 48?h and post-ICU in-hospital mortality a...

  1. Fluorescent and high intensity discharge lamp use in chambers and greenhouses

    Science.gov (United States)

    Langhans, Robert W.

    1994-01-01

    Fluorescent and High Intensity Discharge lamps have opened up great opportunities for researchers to study plant growth under controlled environment conditions and for commercial growers to increase plant production during low/light periods. Specific technical qualities of fluorescent and HID lamps have been critically reviewed. I will direct my remarks to fluorescent and high intensity discharge (HID) lamps in growth chambers, growth rooms, and greenhouses. I will discuss the advantages and disadvantages of using each lamp in growth chambers, growth rooms and greenhouses.

  2. Fluorescent and high intensity discharge lamp use in chambers and greenhouses

    Science.gov (United States)

    Langhans, Robert W.

    1994-03-01

    Fluorescent and High Intensity Discharge lamps have opened up great opportunities for researchers to study plant growth under controlled environment conditions and for commercial growers to increase plant production during low/light periods. Specific technical qualities of fluorescent and HID lamps have been critically reviewed. I will direct my remarks to fluorescent and high intensity discharge (HID) lamps in growth chambers, growth rooms, and greenhouses. I will discuss the advantages and disadvantages of using each lamp in growth chambers, growth rooms and greenhouses.

  3. Mastectomy - discharge

    Science.gov (United States)

    Breast removal surgery - discharge; Nipple-sparing mastectomy - discharge; Total mastectomy - discharge; Simple mastectomy - discharge; Modified radical mastectomy - discharge; Breast cancer - mastectomy -discharge

  4. Fabrication of high-aspect-ratio microgrooves using an electrochemical discharge micromilling process

    Science.gov (United States)

    Han, Min-Seop; Chae, Ki Woon; Min, Byung-Kwon

    2017-05-01

    In this study, we created high-aspect-ratio microgrooves in hard, brittle materials using an electrochemical discharge machining (ECDM) process by introducing microtextured machining tool. To enhance the electrical discharge activity, the morphology of the tool side surface was treated via micro-electrical discharge machining to produce fine microprotrusive patterns. The resulting microtextured surface morphology enhanced the electric field and played a key role in improving the step milling depth in the ECDM process. Using the FEM analysis, the evaluation of the field enhancement factor is also addressed. Our experimental investigation revealed microgrooves having an aspect ratio of 1:4, with high geometric accuracy and crack-free surfaces, using one-step ECDM.

  5. Plasma Emission Characteristics from a High Current Hollow Cathode in an Ion Thruster Discharge Chamber

    Science.gov (United States)

    Foster, John E.; Patterson, Michael J.

    2002-01-01

    The presence of energetic ions produced by a hollow cathodes operating at high emission currents (greater than 5A) has been documented in the literature. In order to further elucidate these findings, an investigation of a high current cathode operating in an ion thruster discharge chamber has been undertaken. Using Langmuir probes, a low energy charged particle analyzer and emission spectroscopy, the behavior of the near-cathode plasma and the emitted ion energy distribution was characterized. The presence of energetic ions was confirmed. It was observed that these ions had energies in excess of the discharge voltage and thus cannot be simply explained by ions falling out of plasma through a potential difference of this order. Additionally, evidence provided by Langmuir probes suggests the existence of a double layer essentially separating the hollow cathode plasma column from the main discharge. The radial potential difference associated with this double layer was measured to be of order the ionization potential.

  6. Attachment style and suicide behaviors in high risk psychiatric inpatients following hospital discharge: The mediating role of entrapment.

    Science.gov (United States)

    Li, Shuang; Galynker, Igor I; Briggs, Jessica; Duffy, Molly; Frechette-Hagan, Anna; Kim, Hae-Joon; Cohen, Lisa J; Yaseen, Zimri S

    2017-11-01

    Insecure attachment is associated with suicidal behavior. This relationship and its possible mediators have not been examined in high-risk psychiatric inpatients with respect to the critical high-risk period following hospital discharge. Attachment styles and perception of entrapment were assessed in 200 high-risk adult psychiatric inpatients hospitalized following suicidal ideation or suicide attempt. Suicidal behaviors were evaluated with the Columbia Suicide Severity Rating Scale at 1-2 months post-discharge. Associations between different attachment styles and suicidal behaviors were assessed and mediation of attachment effects by entrapment was modeled. Fearful attachment was associated with post-discharge suicidal behavior and there was a trend-level negative association for secure attachment. In addition, entrapment mediated the relationship between fearful attachment and suicidal behavior. The current study highlights the mediating role of perceptions of entrapment in the contribution of fearful attachment to suicidal behavior in high-risk patients, suggesting entrapment as potential therapeutic target to prevent suicidal behavior in these individuals. Further research is warranted to establish the mechanisms by which entrapment experiences emerge in patients with insecure attachment styles. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Patterns of Phrenic Nerve Discharge after Complete High Cervical Spinal Cord Injury in the Decerebrate Rat.

    Science.gov (United States)

    Ghali, Michael George Zaki; Marchenko, Vitaliy

    2016-06-15

    Studies conducted since the second half of the 19th century have revealed spontaneous as well as pharmacologically induced phasic/rhythmic discharge in spinal respiratory motor outputs of cats, dogs, rabbits, and neonatal rats following high cervical transection (Tx). The extent to which these various studies validate the existence of a true spinal respiratory rhythm generator remains debated. In this set of studies, we seek to characterize patterns of spontaneous phasic/rhythmic, asphyxia-induced, and pharmacologically induced activity occurring in phrenic nerve (PhN) discharge after complete high cervical (C1-C2) spinal cord transection. Experiments were performed on 20 unanesthetized decerebrate Sprague-Dawley adult male rats. Patterns of spontaneous activity after spinalization included tonic, phasic, slow oscillatory, and long-lasting tonic discharges. Topical application of antagonists of GABAA and glycine receptors to C1- and C2- spinal segments induced left-right synchronized phasic decrementing activity in PhN discharge that was abolished by an additional C2Tx. Asphyxia elicited increases in tonic activity and left-right synchronized gasp-like bursts in PhN discharge, demonstrating the presence of spinal circuits that may underlie a spinal gasping-like mechanism. We conclude that intrinsic slow oscillators and a phasic burst/rhythm generator exist in the spinal cord of the adult rat. If present in humans, this mechanism may be exploited to recover respiratory function in patients sustaining severe spinal cord injury.

  8. Mapping geographic areas of high and low drug adherence in patients prescribed continuing treatment for acute coronary syndrome after discharge.

    Science.gov (United States)

    Hoang, Cuong; Kolenic, Giselle; Kline-Rogers, Eva; Eagle, Kim A; Erickson, Steven R

    2011-10-01

    ABSTRACT STUDY OBJECTIVE: To determine the feasibility of using geographic information system (GIS) technology to identify geographic areas of high and low adherence to cardiovascular drug therapy for treatment of acute coronary syndrome (ACS) in patients discharged from a university-affiliated hospital. Design. Retrospective analysis. A registry of patients admitted to and discharged from a large university-affiliated medical center for the treatment of ACS. Patients. A total of 1081 adults distributed over 300 census tracts who were discharged between April 1999 and December 2004 with a diagnosis of an ACS event of unstable angina or acute myocardial infarction. Data were collected on patient demographics, home addresses, and adherence to four classes of drugs - statins, angiotensin-converting enzyme inhibitors, β-blockers, and aspirin - at 6-12 months after discharge for the ACS index event. A GIS program was used to map patient addresses and adherence data to geographic coordinates. Hot Spot Analysis was used to determine the existence of any spatial clustering patterns in adherence rates. The analysis was performed at the census tract level by using the percentage of nonadherent patients within a census tract to represent adherence for the people living within that tract, standardized by the number of residents in a census tract aged 40 years or older. Hot Spot Analysis identified unique geographic areas of high, neutral, and low adherence in the southeast area. Highly adherent census tracts were primarily located in and around the city where the university hospital and clinics are located. Areas of low adherence were located to the west, southwest, and southeast of the city. All other census tracts were considered neutral in adherence rates. Mapping geographic areas of drug adherence is feasible with use of GIS technology, with spatial mapping able to detect areas of varying levels of adherence. Future research should examine local-level factors associated

  9. Features of high quality discharge planning for patients following acute myocardial infarction.

    Science.gov (United States)

    Cherlin, Emily J; Curry, Leslie A; Thompson, Jennifer W; Greysen, S Ryan; Spatz, Erica; Krumholz, Harlan M; Bradley, Elizabeth H

    2013-03-01

    Hospital discharge planning is required as a Medicare Condition of Participation (CoP), and is essential to the health and safety for all patients. However, there have been no studies examining specific hospital discharge processes, such as patient education and communication with primary care providers, in relation to hospital 30-day risk standardized mortality rates (RSMRs) for patients with acute myocardial infarction (AMI). To identify hospital discharge processes that may be associated with better performance in hospital AMI care as measured by RSMR. We conducted a qualitative study of U.S. Hospitals, which were selected based on their RSMR reported by the Centers for Medicare & Medicaid Services (CMS) Hospital Compare website for the most recent data available (January 1, 2005 - December 31, 2007). We selected hospitals that ranked in the top 5 % and the bottom 5 % of RSMR for the two consecutive years. We focused on hospitals at the extreme ends of the range in RSMR, known as deviant case sampling. We excluded hospitals that did not have the ability to perform percutaneous coronary intervention in order to decrease the heterogeneity in our sample. Participants included key hospital clinical and administrative staff most involved in discharge planning for patients admitted with AMI. We conducted 14 site visits and 57 in-depth interviews using a standard discussion guide. We employed a grounded theory approach and used the constant comparative method to generate recurrent and unifying themes. We identified five broad discharge processes that distinguished higher and lower performing hospitals: 1) initiating discharge planning upon patient admission; 2) using multidisciplinary case management services; 3) ensuring that a follow-up plan is in place prior to discharge; 4) providing focused education sessions for both the patient and family; and 5) contacting the primary care physician regarding the patient's hospitalization and follow-up care plan

  10. A Muskingum-based methodology for river discharge estimation and rating curve development under significant lateral inflow conditions

    Science.gov (United States)

    Barbetta, Silvia; Moramarco, Tommaso; Perumal, Muthiah

    2017-11-01

    Quite often the discharge at a site is estimated using the rating curve developed for that site and its development requires river flow measurements, which are costly, tedious and dangerous during severe floods. To circumvent the conventional rating curve development approach, Perumal et al. in 2007 and 2010 applied the Variable Parameter Muskingum Stage-hydrograph (VPMS) routing method for developing stage-discharge relationships especially at those ungauged river sites where stage measurements and details of section geometry are available, but discharge measurements are not made. The VPMS method enables to estimate rating curves at ungauged river sites with acceptable accuracy. But the application of the method is subjected to the limitation of negligible presence of lateral flow within the routing reach. To overcome this limitation, this study proposes an extension of the VPMS method, henceforth, known herein as the VPMS-Lin method, for enabling the streamflow assessment even when significant lateral inflow occurs along the river reach considered for routing. The lateral inflow is estimated through the continuity equation expressed in the characteristic form as advocated by Barbetta et al. in 2012. The VPMS-Lin, is tested on two rivers characterized by different geometric and hydraulic properties: 1) a 50 km reach of the Tiber River in (central Italy) and 2) a 73 km reach of the Godavari River in the peninsular India. The study demonstrates that both the upstream and downstream discharge hydrographs are well reproduced, with a root mean square error equal on average to about 35 and 1700 m3 s-1 for the Tiber River and the Godavari River case studies, respectively. Moreover, simulation studies carried out on a river stretch of the Tiber River using the one-dimensional hydraulic model MIKE11 and the VPMS-Lin models demonstrate the accuracy of the VMPS-Lin model, which besides enabling the estimation of streamflow, also enables the estimation of reach averaged

  11. Comparison of readmission rates between groups with early versus late discharge after vaginal or cesarean delivery: a retrospective analyzes of 14,460 cases.

    Science.gov (United States)

    Bostanci Ergen, Evrim; Ozkaya, Enis; Eser, Ahmet; Abide Yayla, Cigdem; Kilicci, Cetin; Yenidede, Ilter; Eser, Semra Kayatas; Karateke, Ates

    2017-04-25

    The aim of this retrospective analysis was to show the readmission rate of cases with and without early discharge following vaginal or cesarean delivery. After exclusion of cases with pregnancy, delivery and neonatal complications, a total of 14,460 cases who delivered at Zeynep Kamil Women and Children's Health Training and Research Hospital were retrospectively screened from hospital database. Subjects were divided into two groups as Group 1: early discharge (n = 6802) and Group 2: late discharge (n = 7658). Groups were compared in terms of readmission rates and indications for readmission. There were 6802 cases with early discharge whereas the remaining women were discharged after 24 h for vaginal delivery and 48 h following cesarean delivery on regular bases. Among cases with early discharge, 205 (3%) cases readmitted to emergency service with variable indications, while there were 216 (2.8%) readmitted women who were discharged on regular bases. Most common indication for readmission was wound infection in both groups. Neonatal sex distributions were similar between groups (p > .05), where as there was a higher rate of cesarean deliveries in Group 2 (p discharge (p discharges following vaginal or cesarean delivery without any mortality or permanent morbidity and cost analyses revealed 68 Turkish liras lower cost with early discharge.

  12. Robotic coronary artery bypass grafting decreases 30-day complication rate, length of stay, and acute care facility discharge rate compared with conventional surgery.

    Science.gov (United States)

    Leyvi, Galina; Forest, Stephen J; Srinivas, Vankeepuram S; Greenberg, Mark; Wang, Nan; Mais, Alec; Snyder, Max J; DeRose, Joseph J

    2014-01-01

    The objective of this study was to compare the short-term outcomes of robotic with conventional on-pump coronary artery bypass grafting (CABG). The study population included 2091 consecutive patients who underwent either conventional or robotic CABG from January 2007 to March 2012. Preoperative, intraoperative, and 30-day postoperative variables were collected for each group. To compare the incidence of rapid recovery between conventional and robotic CABG, the surrogate variables of early discharge and discharge to home (vs rehabilitation or acute care facility) were evaluated. A multivariate logistic regression analysis was used. One hundred fifty robotic and 1619 conventional CABG cases were analyzed. Multivariate logistic regression analysis demonstrated that robotic surgery was a strong predictor of lower 30-day complications [odds ratio (OR), 0.24; P = 0.005], short length of stay (OR, 3.31; P < 0.001), and decreased need for an acute care facility (OR, 0.55; P = 0.032). In the presence of complications (New York State Complication Composite), the robotic technique was not associated with a change in discharge status. In this retrospective review, robotic CABG was associated with a lower 30-day complication rate, a shorter length of stay, and a lower incidence of acute care facility discharge than conventional on-pump CABG. It may suggest a more rapid recovery to preoperative status after robotic surgery; however, only a randomized prospective study could confirm the advantages of a robotic approach.

  13. High explosives vapor detection by atmospheric sampling glow discharge ionization/tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    McLuckey, S.A.; Goeringer, D.E.; Asano, K.G. [Oak Ridge National Lab., TN (United States). Chemical and Analytical Sciences Div.

    1996-02-01

    The combination of atmospheric sampling glow discharge ionization with tandem mass spectrometry for the detection of traces of high explosives is described. Particular emphasis is placed on use of the quadrupole ion trap as the type of tandem mass spectrometer. Atmospheric sampling glow discharge provides a simple, rugged, and efficient means for anion formation while the quadrupole ion trap provides for efficient tandem mass spectrometry. Mass selective ion accumulation and non-specific ion activation methods can be used to overcome deleterious effects arising from ion/ion interactions. Such interactions constitute the major potential technical barrier to the use of the ion trap for real-time monitoring of targeted compounds in uncontrolled and highly variable matrices. Tailored waveforms can be used to effect both mass selective ion accumulation and ion activation. Concatenated tailored waveforms allow for both functions in a single experiment thereby providing the capability for monitoring several targeted species simultaneously. The combination of atmospheric sampling glow discharge ionization with a state-of-the-art analytical quadrupole ion trap is a highly sensitive and specific detector for traces of high explosives. The combination is also small and inexpensive relative to virtually any other form of tandem mass spectrometry. The science and technology underlying the glow discharge/ion trap combination is sufficiently mature to form the basis for an engineering effort to make the detector portable. 85 refs.

  14. High Sensitive Distinction of Discharge in Air by Daubechies Wavelet Transform

    Science.gov (United States)

    Yamada, Ioya; Kubota, Hisashi; Inui, Akifumi; Kawaguchi, Yoshihiro

    If partial discharge occurs in high voltage apparatus, it is unfavorable in view point of its insulation reliability, because they might develop into its insulation degradation or its electrical breakdown. In order to raise the insulation reliability of an apparatus, it is important to detect a minute partial discharge with sufficient sensitivity, especially suppressing background noise. This paper deals with the waveform processing technology by the Daubechies wavelet transform to make relief of the partial discharge signal from a measured noise-containing signal. On this basic idea, here is discussed that the optimal Daubechies order and its level have a close relation with the detection impedance and the sampling interval of the measured signal. Since the partial discharge waveform measured with the detection impedance of parallel circuits of RLC tuned into a damped oscillatory pulse, it has been demonstrated that the Daubechies wavelet transform is effective in discriminating the partial discharge signal from the measured noise-containing signal. Moreover, by choosing suitably the Daubechies order and its level applied to the measured data, it has been clarified that even a minute glow corona which have been masked by the background noise, and also the streamer corona turns into clear appearance on the transformed wave with sufficient sensitivity.

  15. Modelling the Dynamic Interaction Power System Lamp - Application to High Pressure Mercury Gas Discharge Lamps

    Directory of Open Access Journals (Sweden)

    ZIANE, M.

    2007-11-01

    Full Text Available The aim of this paper is to study the dynamic behaviour of a plant constituted by an electrical power system and a gas discharge lamp, this latter, increasingly used in street lighting, remains a nonlinear load element. Various approaches are used to represent it, one is the approximation of the discharge represented by a hot "channel", which verifies the assumption of local thermodynamic equilibrium [LTE] or the polynomial form of the conductance variation. A calculation procedure, based on "channel" approximation of the high pressure mercury (HPM gas-discharge lamp, is developed to determine the physical and electric magnitudes, which characterize the dynamic behavior of the couple "lamp-electrical power system". The evolution of the lamp properties when principal parameters of the discharge (pressure of mercury, voltage supply, frequency are varying were studied and analyzed. We show the concordance between simulation, calculations and measurements for electric, energetic or irradiative characteristics. The model reproduces well the evolution of properties of the supply when principal parameters of the discharge vary.

  16. Advanced High-Frequency Electronic Ballasting Techniques for Gas Discharge Lamps

    OpenAIRE

    Tao, Fengfeng

    2001-01-01

    Small size, light weight, high efficacy, longer lifetime and controllable output are the main advantages of high-frequency electronic ballasts for gas discharge lamps. However, power line quality and electromagnetic interference (EMI) issues arise when a simple peak rectifying circuit is used. To suppress harmonic currents and improve power factor, input-current-shaping (ICS) or power-factor-correction (PFC) techniques are necessary. This dissertation addresses advanced high-frequency elec...

  17. Spectral characteristics of optical discharge in a high-speed methane-air jet

    Science.gov (United States)

    Zudov, V. N.

    2017-06-01

    Results of gasdynamic and spectroscopic investigations of optical discharge in the subsupersonic flow of a homogeneous fuel-air (CH4 + air) mixtures are presented. The combustion was initiated and maintained by optical discharge created using a CO2 laser. The laser radiation propagated across the flow and was focused by a lens on the axis of the supersonic jet ( M = 2). Emission-spectroscopy techniques provided data on the composition of radiating combustion products and the intensity of components emitted in the region of optical discharge. Patterns of Toepler's visualization of the flow structure in the schlieren scheme are presented. The images were monitored by a high-speed video camera operating at an exposure time of 1.5 μs and a frame frequency of 1000 s-1.

  18. High-Rate Receiver Design Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose an initial architectural and preliminary hardware design study for a high-rate receiver capable of decoding modulation suites specified by CCSDS 413.0-G-1...

  19. Continuous extraction of phenolic compounds from pomegranate peel using high voltage electrical discharge.

    Science.gov (United States)

    Xi, Jun; He, Lang; Yan, Liang-Gong

    2017-09-01

    Pomegranate peel, a waste generated from fruit processing industry, is a potential source of phenolic compounds that are known for their anti-oxidative properties. In this study, a continuous high voltage electrical discharge (HVED) extraction system was for the first time designed and optimized for phenolic compounds from pomegranate peel. The optimal conditions for HVED were: flow rate of materials 12mL/min, electrodes gap distance 3.1mm (corresponding to 29kV/cm of electric field intensity) and liquid to solid ratio 35mL/g. Under these conditions, the experimental yield of phenolic compounds was 196.7±6.4mg/g, which closely agreed with the predicted value (199.83mg/g). Compared with the warm water maceration, HVED method possessed higher efficiency for the extraction of phenolic compounds. The results demonstrated that HVED technique could be a very effective method for continuous extraction of natural compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Using IDA to Understand Electron Temperature Structures in High Temperature Discharges in the Madison Symmetric Torus

    Science.gov (United States)

    Reusch, L. M.; Galante, M. E.; den Hartog, D. J.; Franz, P.; Johnson, J. R.; McGarry, M. B.; Stephens, H. D.

    2014-10-01

    The Madison Symmetric Torus (MST) Reversed-Field Pinch is equipped with two independent electron temperature (Te) diagnostics: Thomson scattering (TS) and double-filter soft x-ray (SXR). Both diagnostics are able to measure Te at a rate up to 25 kHz and are in good qualitative agreement in the hot plasma core, where Te > 1 keV. We are able to combine information from both TS and SXR diagnostics along with prior physics knowledge using integrated data analysis techniques (IDA) [R. Fischer and A. Dinklage, Rev. Sci. Instrum. 75, 4237 (2004)] to improve the precision and utility of Te measurements on MST. Using IDA, there is a factor of 4 improvement in the uncertainty of all temperature measurements. We have also implemented a Markov Chain Monte Carlo analysis for analyzing the various temperature structures that MST is capable of sustaining. We have compared emissivity maps and flux surface reconstructions to the electron temperatures from several discharges to characterize the phenomenology of temperature structures in high temperature plasmas in MST. Work supported by US DOE and NSF.

  1. Explosive Processes on Cathode while Forming Nanosecond Pulsed Discharge of High Pressure

    Directory of Open Access Journals (Sweden)

    A. Hashimov

    2012-01-01

    Full Text Available The paper is devoted to research of cathode surfaces with different curvature radius (r = 1–8 mm while forming nanosecond pulsed discharge in dense air. Influence of field and air pressure heterogeneity rate in gas gap on size of micro-craters being formed on working cathode surface after pulsed effect has been shown in the paper. The paper reveals a maximum expansion of separate micro-crater size on cathode surface with small curvature radius.

  2. Can hydraulic-modelled rating curves reduce uncertainty in high flow data?

    Science.gov (United States)

    Westerberg, Ida; Lam, Norris; Lyon, Steve W.

    2017-04-01

    Flood risk assessments rely on accurate discharge data records. Establishing a reliable rating curve for calculating discharge from stage at a gauging station normally takes years of data collection efforts. Estimation of high flows is particularly difficult as high flows occur rarely and are often practically difficult to gauge. Hydraulically-modelled rating curves can be derived based on as few as two concurrent stage-discharge and water-surface slope measurements at different flow conditions. This means that a reliable rating curve can, potentially, be derived much faster than a traditional rating curve based on numerous stage-discharge gaugings. In this study we compared the uncertainty in discharge data that resulted from these two rating curve modelling approaches. We applied both methods to a Swedish catchment, accounting for uncertainties in the stage-discharge gauging and water-surface slope data for the hydraulic model and in the stage-discharge gauging data and rating-curve parameters for the traditional method. We focused our analyses on high-flow uncertainty and the factors that could reduce this uncertainty. In particular, we investigated which data uncertainties were most important, and at what flow conditions the gaugings should preferably be taken. First results show that the hydraulically-modelled rating curves were more sensitive to uncertainties in the calibration measurements of discharge than water surface slope. The uncertainty of the hydraulically-modelled rating curves were lowest within the range of the three calibration stage-discharge gaugings (i.e. between median and two-times median flow) whereas uncertainties were higher outside of this range. For instance, at the highest observed stage of the 24-year stage record, the 90% uncertainty band was -15% to +40% of the official rating curve. Additional gaugings at high flows (i.e. four to five times median flow) would likely substantially reduce those uncertainties. These first results show

  3. Stress-induced impairment of a working memory task: role of spiking rate and spiking history predicted discharge.

    Science.gov (United States)

    Devilbiss, David M; Jenison, Rick L; Berridge, Craig W

    2012-01-01

    Stress, pervasive in society, contributes to over half of all work place accidents a year and over time can contribute to a variety of psychiatric disorders including depression, schizophrenia, and post-traumatic stress disorder. Stress impairs higher cognitive processes, dependent on the prefrontal cortex (PFC) and that involve maintenance and integration of information over extended periods, including working memory and attention. Substantial evidence has demonstrated a relationship between patterns of PFC neuron spiking activity (action-potential discharge) and components of delayed-response tasks used to probe PFC-dependent cognitive function in rats and monkeys. During delay periods of these tasks, persistent spiking activity is posited to be essential for the maintenance of information for working memory and attention. However, the degree to which stress-induced impairment in PFC-dependent cognition involves changes in task-related spiking rates or the ability for PFC neurons to retain information over time remains unknown. In the current study, spiking activity was recorded from the medial PFC of rats performing a delayed-response task of working memory during acute noise stress (93 db). Spike history-predicted discharge (SHPD) for PFC neurons was quantified as a measure of the degree to which ongoing neuronal discharge can be predicted by past spiking activity and reflects the degree to which past information is retained by these neurons over time. We found that PFC neuron discharge is predicted by their past spiking patterns for nearly one second. Acute stress impaired SHPD, selectively during delay intervals of the task, and simultaneously impaired task performance. Despite the reduction in delay-related SHPD, stress increased delay-related spiking rates. These findings suggest that neural codes utilizing SHPD within PFC networks likely reflects an additional important neurophysiological mechanism for maintenance of past information over time. Stress

  4. Longitudinally excited CO2 laser with short laser pulse operating at high repetition rate

    Science.gov (United States)

    Li, Jianhui; Uno, Kazuyuki; Akitsu, Tetsuya; Jitsuno, Takahisa

    2016-11-01

    A short-pulse longitudinally excited CO2 laser operating at a high repetition rate was developed. The discharge tube was made of a 45 cm-long or 60 cm-long dielectric tube with an inner diameter of 16 mm and two metallic electrodes at the ends of the tube. The optical cavity was formed by a ZnSe output coupler with a reflectivity of 85% and a high-reflection mirror. Mixed gas (CO2:N2:He = 1:1:2) was flowed into the discharge tube. A high voltage of about 33 kV with a rise time of about 200 ns was applied to the discharge tube. At a repetition rate of 300 Hz and a gas pressure of 3.4 kPa, the 45 cm-long discharge tube produced a short laser pulse with a laser pulse energy of 17.5 mJ, a spike pulse energy of 0.2 mJ, a spike width of 153 ns, and a pulse tail length of 90 μs. The output power was 5.3 W. The laser pulse waveform did not depend on the repetition rate, but the laser beam profile did. At a low repetition rate of less than 50 Hz, the laser beam had a doughnut-like shape. However, at a high repetition rate of more than 150 Hz, the discharge concentrated at the center of the discharge tube, and the intensity at the center of the laser beam was higher. The laser beam profile depended on the distribution of the discharge. An output power of 7.0 W was achieved by using the 60 cm-long tube.

  5. Deflagration-to-detonation transition control by high voltage nanosecond discharges

    Science.gov (United States)

    Starikovskii, Andrei; Rakitin, Aleksandr

    2008-10-01

    A smooth square detonation tube with a transverse size of 20 mm and a single-cell discharge chamber has been assembled to study DDT mechanisms under initiation by high-voltage nanosecond discharges. Stoichiometric propane-oxygen mixture was used at initial pressures of 0.3 and 1 bar. Two general mechanisms of DDT initiation have been observed and explained under the experimental conditions. When initiated by a spark, the mixture ignites simultaneously over the volume of the discharge channel, producing a shock wave with Mach number over 2 and a flame wave. The waves then form an accelerating complex, and, after it reaches a certain velocity, an adiabatic explosion occurs resulting in DDT. At 1 bar of initial pressure, the DDT length and time do not exceed 50 mm and 50 μs, respectively. Under streamer initiation, the mixture inside the discharge channel is excited non-uniformly. The mixture is first ignited at the hottest spot with the shortest ignition delay, which is at the high voltage electrode tip. Originating at this point, the ignition wave starts propagating along the channel and accelerates up to the CJ velocity value. The initiation energy is by an order of magnitude lower for the streamer-gradient mode when compared to the spark initiation.

  6. Effect of secondary electron emission on subnanosecond breakdown in high-voltage pulse discharge

    Science.gov (United States)

    Schweigert, I. V.; Alexandrov, A. L.; Gugin, P.; Lavrukhin, M.; Bokhan, P. A.; Zakrevsky, Dm E.

    2017-11-01

    The subnanosecond breakdown in open discharge may be applied for producing superfast high power switches. Such fast breakdown in high-voltage pulse discharge in helium was explored both in experiment and in kinetic simulations. The kinetic model of electron avalanche development was developed using PIC-MCC technique. The model simulates motion of electrons, ions and fast helium atoms, appearing due to ions scattering. It was shown that the mechanism responsible for ultra-fast breakdown development is the electron emission from cathode. The photoemission and emission by ions or fast atoms impact is the main reason of current growth at the early stage of breakdown, but at the final stage, when the voltage on discharge gap drops, the secondary electron emission (SEE) is responsible for subnanosecond time scale of current growth. It was also found that the characteristic time of the current growth τS depends on the SEE yield of the cathode material. Three types of cathode material (titanium, SiC, and CuAlMg-alloy) were tested. It is shown that in discharge with SiC and CuAlMg-alloy cathodes (which have enhanced SEE) the current can increase with a subnanosecond characteristic time as small as τS = 0.4 ns, for the pulse voltage amplitude of 5- 12 kV..

  7. New pixelized Micromegas detector with low discharge rate for the COMPASS experiment

    CERN Document Server

    Neyret, D.; Anfreville, M.; Bedfer, Y.; Burtin, E.; Coquelet, C.; d'Hose, N.; Desforge, D.; Giganon, A.; Jourde, D.; Kunne, F.; Magnon, A.; Makke, N.; Marchand, C.; Paul, B.; Platchkov, S.; Thibaud, F.; Usseglio, M.; Vandenbroucke, M.

    2012-01-01

    New Micromegas (Micro-mesh gaseous detectors) are being developed in view of the future physics projects planned by the COMPASS collaboration at CERN. Several major upgrades compared to present detectors are being studied: detectors standing five times higher luminosity with hadron beams, detection of beam particles (flux up to a few hundred of kHz/mm^{2}, 10 times larger than for the present Micromegas detectors) with pixelized read-out in the central part, light and integrated electronics, and improved robustness. Two solutions of reduction of discharge impact have been studied, with Micromegas detectors using resistive layers and using an additional GEM foil. Performance of such detectors has also been measured. A large size prototypes with nominal active area and pixelized read-out has been produced and installed at COMPASS in 2010. In 2011 prototypes featuring an additional GEM foil, as well as an resistive prototype, are installed at COMPASS and preliminary results from those detectors presented very go...

  8. Environmental and biotechnological applications of high-voltage pulsed discharges in water

    Science.gov (United States)

    Sato, Masayuki

    2008-05-01

    A high-voltage pulse has wide application in fields such as chemistry, physics and biology and their combinations. The high-voltage pulse forms two kinds of physical processes in water, namely (a) a pulsed electric field (PEF) in the parallel electrode configuration and (b) plasma generation by a pulsed discharge in the water phase with a concentrated electric field. The PEF can be used for inactivation of bacteria in liquid foods as a non-thermal process, and the underwater plasma is applicable not only for the decomposition of organic materials in water but also for biological treatment of wastewater. These discharge states are controlled mainly by the applied pulse voltage and the electrode shape. Some examples of environmental and biotechnological applications of a high-voltage pulse are reviewed.

  9. High-brightness VUV sources based on plasma-dynamic magnetoplasma compressor discharges in gases

    Science.gov (United States)

    Kamrukov, A. S.; Kozlov, N. P.; Protasov, Iu. S.; Shashkovskii, S. G.

    1989-02-01

    The paper is concerned with the physical and technical aspects of the use of plasma-dynamic methods for generating high-power electromagnetic pulses over a wide spectral region, particularly in the UV and VUV spectral bands. In the experimental studies reviewed here, these methods are implemented by using high-current discharges of an erosion-type magnetoplasma compressor in gases. Approaches to the optimization of the energy and spectral-brightness characteristics of such discharges are discussed. The development of high power (1.5 GW) open-type plasma sources with a tunable emission spectrum and a light efficiency of 40-60 percent which can operate in the repetitively pulsed mode is reported.

  10. Response surface modelling of tool electrode wear rate and material removal rate in micro electrical discharge machining of Inconel 718

    DEFF Research Database (Denmark)

    Puthumana, Govindan

    2017-01-01

    Inconel 718 is a corrosion-resistant and high strength nickel-based alloy with wide range of applications includingcomponents for cryogenic tankage, liquid fueled rockets and casings for aircraft engines. The material is characterizedby high hardness, high temperature strength, low thermal...

  11. Thrombus Formation at High Shear Rates.

    Science.gov (United States)

    Casa, Lauren D C; Ku, David N

    2017-06-21

    The final common pathway in myocardial infarction and ischemic stroke is occlusion of blood flow from a thrombus forming under high shear rates in arteries. A high-shear thrombus forms rapidly and is distinct from the slow formation of coagulation that occurs in stagnant blood. Thrombosis at high shear rates depends primarily on the long protein von Willebrand factor (vWF) and platelets, with hemodynamics playing an important role in each stage of thrombus formation, including vWF binding, platelet adhesion, platelet activation, and rapid thrombus growth. The prediction of high-shear thrombosis is a major area of biofluid mechanics in which point-of-care testing and computational modeling are promising future directions for clinically relevant research. Further research in this area will enable identification of patients at high risk for arterial thrombosis, improve prevention and treatment based on shear-dependent biological mechanisms, and improve blood-contacting device design to reduce thrombosis risk.

  12. Variation in rates of ICU readmissions and post-ICU in-hospital mortality and their association with ICU discharge practices

    NARCIS (Netherlands)

    Sluisveld, N. van; Bakhshi-Raiez, F.; Keizer, N. de; Holman, R.; Westert, G.P.; Wollersheim, H.C.; Hoeven, J.G. van der; Zegers, M.

    2017-01-01

    BACKGROUND: Variation in intensive care unit (ICU) readmissions and in-hospital mortality after ICU discharge may indicate potential for improvement and could be explained by ICU discharge practices. Our objective was threefold: (1) describe variation in rates of ICU readmissions within 48 h and

  13. Variation in rates of ICU readmissions and post-ICU in-hospital mortality and their association with ICU discharge practices

    NARCIS (Netherlands)

    van Sluisveld, Nelleke; Bakhshi-Raiez, Ferishta; de Keizer, Nicolette; Holman, Rebecca; Wester, Gert; Wollersheim, Hub; van der Hoeven, Johannes G.; Zegers, Marieke

    2017-01-01

    Variation in intensive care unit (ICU) readmissions and in-hospital mortality after ICU discharge may indicate potential for improvement and could be explained by ICU discharge practices. Our objective was threefold: (1) describe variation in rates of ICU readmissions within 48 h and post-ICU

  14. NIPPLE DISCHARGE

    Directory of Open Access Journals (Sweden)

    T. N. Bukharova

    2008-01-01

    Full Text Available According to the data available in the literature, as high as 50% of women have benign breast tumors frequently accompanied by nip- ple discharge. Nipple discharge may be serous, bloody, purulent, and colostric. The most common causes are breast abscess, injury, drugs, prolactinoma, intraductal pappiloma, ductal ectasia, intraductal cancer (not more than 10%.

  15. Commentary on Masel et al. Predicting discharge of palliative care inpatients by measuring their heart rate variability.

    Science.gov (United States)

    Thurston, Andrew; Arnold, Robert

    2015-01-01

    The accurate determination of prognosis is a challenging and important aspect of end of life care. A more accurate prognosis provides patients and their families' time to plan and prepare for the end of life, and prioritize care based on individual goals and values. While a number of prognostic tools and indices provide insight into a patient's general prognosis, the use of heart rate variability (HRV) as a predictor of live discharge from a palliative care unit (PCU) is a unique approach to exploring non-invasive ways for more accurate prognostication.

  16. Discharge rate balancing control strategy based on dynamic consensus algorithm for energy storage units in AC microgrids

    DEFF Research Database (Denmark)

    Guan, Yajuan; Meng, Lexuan; Li, Chendan

    2017-01-01

    A dynamic consensus algorithm-based coordinated secondary control with an autonomous current-sharing control strategy is proposed in this paper for balancing discharge rate of energy storage systems (ESSs) in an islanded AC microgrid. The dynamic consensus algorithm is applied for information...... linearized state-space model in z-domain, both the system stability and parameter sensitivity were analyzed. A comparison between experimental results obtained from using the conventional power sharing control and those obtained from the proposed coordinated control using a setup with three 2.2 kW DG units...

  17. Experimental Investigation of Surface Layer Properties of High Thermal Conductivity Tool Steel after Electrical Discharge Machining

    Directory of Open Access Journals (Sweden)

    Rafał Świercz

    2017-12-01

    Full Text Available New materials require the use of advanced technology in manufacturing complex shape parts. One of the modern materials widely used in the tool industry for injection molds or hot stamping dies is high conductivity tool steel (HTCS 150. Due to its hardness (55 HRC and thermal conductivity at 66 W/mK, this material is difficult to machine by conventional treatment and is being increasingly manufactured by nonconventional technology such as electrical discharge machining (EDM. In the EDM process, material is removed from the workpiece by a series of electrical discharges that cause changes to the surface layers properties. The final state of the surface layer directly influences the durability of the produced elements. This paper presents the influence of EDM process parameters: discharge current Ic and the pulse time ton on surface layer properties. The experimental investigation was carried out with an experimental methodology design. Surface layers properties including roughness 3D parameters, the thickness of the white layer, heat affected zone, tempered layer and occurring micro cracks were investigated and described. The influence of the response surface methodology (RSM of discharge current Ic and the pulse time ton on the thickness of the white layer and roughness parameters Sa, Sds and Ssc were described and established.

  18. High frequency excitation waveform for efficient operation of a xenon excimer dielectric barrier discharge lamp

    Science.gov (United States)

    Beleznai, Sz; Mihajlik, G.; Maros, I.; Balázs, L.; Richter, P.

    2010-01-01

    The application of a high frequency (~2.5 MHz) burst (amplitude-modulated sinusoidal) excitation voltage waveform is investigated for driving a fluorescent dielectric barrier discharge (DBD) light source. The excitation waveform presents a novel method for generating spatially stable homogeneous Xe DBD possessing a high conversion efficiency from electrical energy to VUV Xe_{2}^{\\ast} excimer radiation (~172 nm), even at a significantly higher electrical energy deposition than realized by pulsed excitation. Simulation and experimental results predict discharge efficiencies around 60%. Lamp efficacy above 74 lm W-1 has been achieved. VUV emission and loss mechanisms are investigated extensively and the performance of burst and pulsed waveforms is compared both theoretically and experimentally.

  19. High frequency excitation waveform for efficient operation of a xenon excimer dielectric barrier discharge lamp

    Energy Technology Data Exchange (ETDEWEB)

    Beleznai, Sz; Mihajlik, G; Richter, P [Department of Atomic Physics, Budapest University of Technology and Economics, 3-9.Muegyetem rkp., Budapest H-1111 (Hungary); Maros, I; Balazs, L, E-mail: beleznai@dept.phy.bme.h [GE Consumer and Industrial-Lighting, 77 Vaci ut, Budapest H-1344 (Hungary)

    2010-01-13

    The application of a high frequency ({approx}2.5 MHz) burst (amplitude-modulated sinusoidal) excitation voltage waveform is investigated for driving a fluorescent dielectric barrier discharge (DBD) light source. The excitation waveform presents a novel method for generating spatially stable homogeneous Xe DBD possessing a high conversion efficiency from electrical energy to VUV Xe{sub 2}{sup *} excimer radiation ({approx}172 nm), even at a significantly higher electrical energy deposition than realized by pulsed excitation. Simulation and experimental results predict discharge efficiencies around 60%. Lamp efficacy above 74 lm W{sup -1} has been achieved. VUV emission and loss mechanisms are investigated extensively and the performance of burst and pulsed waveforms is compared both theoretically and experimentally.

  20. High Strain Rate Characterisation of Composite Materials

    DEFF Research Database (Denmark)

    Eriksen, Rasmus Normann Wilken

    -reinforced polymers, were considered, and it was first shown that the loading history controls equilibrium process. Then the High-speed servo-hydraulic test machine was analysed in terms its ability to create a state of constant strain rate in the specimen. The invertible inertial forces in the load train prevented...... a linear elastic specimen to reach a state of constant strain rate before fracture. This was in contrast to ductile materials, which are widely tested with for the High-speed servohydraulic test machine. The development of the analysis and the interpretation of the results, were based on the experience...... from designing and constructing a high-speed servo-hydraulic test machine and by performing a comprehensive test series. The difficulties encountered in the test work could be addressed with the developed analysis. The conclusion was that the High-speed servo-hydraulic test machine is less suited...

  1. High resolution measurement of the glycolytic rate

    Directory of Open Access Journals (Sweden)

    Carla X Bittner

    2010-09-01

    Full Text Available The glycolytic rate is sensitive to physiological activity, hormones, stress, aging and malignant transformation. Standard techniques to measure the glycolytic rate are based on radioactive isotopes, are not able to resolve single cells and have poor temporal resolution, limitations that hamper the study of energy metabolism in the brain and other organs. A new method is described in this article, which makes use of a recently-developed FRET glucose nanosensor to measure the rate of glycolysis in single cells with high temporal resolution. Used in cultured astrocytes, the method showed for the first time that glycolysis can be activated within seconds by a combination of glutamate and K+, supporting a role for astrocytes in neurometabolic and neurovascular coupling in the brain. It was also possible to make a direct comparison of metabolism in neurons and astrocytes lying in close proximity, paving the way to a high-resolution characterization of brain energy metabolism. Single-cell glycolytic rates were also measured in fibroblasts, adipocytes, myoblasts and tumor cells, showing higher rates for undifferentiated cells and significant metabolic heterogeneity within cell types. This method should facilitate the investigation of tissue metabolism at the single-cell level and is readily adaptable for high-throughput analysis.

  2. Influence of atoms with high ionization potentials on a discharge in crossed E and H fields

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, A.A.; Timchenko, N.N.; Khripunov, B.I.; Shapkin, V.V.

    1980-11-01

    We consider processes connected with the separation of elements in a fully ionized plasma centrifuge with a plasma gun discharge in crossed E and H fields. We analyze the influence of atoms with high ionization potentials on the separation parameters, the value of the transverse ion current, and the separation coefficient. We not the role played by the radial electric field in the gas ionization processes and in the resulting growth of ion acoustic instabilities.

  3. A powerful electrohydrodynamic flow generated by a high-frequency dielectric barrier discharge in a gas

    Energy Technology Data Exchange (ETDEWEB)

    Nebogatkin, S. V.; Rebrov, I. E.; Khomich, V. Yu.; Yamshchikov, V. A., E-mail: yamschikov52@mail.ru [Russian Academy of Sciences, Institute for Electrophysics and Electric Power (Russian Federation)

    2016-01-15

    Theoretical and experimental studies of an electrohydrodynamic flow induced by a high-frequency dielectric barrier discharge distributed over a dielectric surface in a gas have been conducted. Dependences of the ion current, the gas flow velocity, and the spatial distributions thereof on the parameters of the power supply of the plasma ion emitter and an external electric field determined by the collector grid voltage have been described.

  4. On the complex ageing characteristics of high-power LiFePO4/graphite battery cells cycled with high charge and discharge currents

    DEFF Research Database (Denmark)

    Groot, Jens; Swierczynski, Maciej Jozef; Stroe, Ana-Irina

    2015-01-01

    Li-ion batteries are known to undergo complex ageing processes, where the operating conditions have a profound and non-linear effect on both calendar life and cycle life. This is especially a challenge for the automotive industry, where the requirements on product lifetime and reliability...... are demanding. The aim of the present work is to quantify the ageing in terms of capacity fade and impedance growth as a function of operating conditions typical to high-power automotive applications; high charge and discharge rate, elevated temperatures and wide state-of-charge windows. The cycle life of 34...

  5. High Rate Performing Li-ion Battery

    Science.gov (United States)

    2015-02-09

    permeable to lithium ions and efficient in transferring the electrons into/from the LVP surface to the corresponding current collector. a) b) c) d) e...PO4)3/C for High Rate Lithium-ion Battery Applications”, Lee Hwang Sheng, Nail Suleimanov, Vishwanathan Ramar, Mangayarkarasi Murugan, Kuppan

  6. Concomitant chemoradiotherapy with high dose rate brachytherapy ...

    African Journals Online (AJOL)

    Purpose: This study aims to report the incidence of treatment-induced acute toxicities, local control and survival of patients with cervix cancer treated by external beam radiotherapy (EBR) and high-dose-rate (HDR) brachytherapy concomitant with weekly Cisplatin chemotherapy. Methods: Forty patients with FIGO Stages IB2 ...

  7. Fluorescent and high intensity discharge lamp use in chambers and greenhouses

    Energy Technology Data Exchange (ETDEWEB)

    Langhans, R.W. [Cornell Univ., Ithaca, NY (United States)

    1994-12-31

    Fluorescent and High Intensity Discharge lamps have opened up great opportunities for researchers to study plant growth under controlled environment conditions and for commercial growers to increase plant production during low/light periods. This report describes the advantages and disadvantages of using each lamp in growth chambers, growth rooms and greenhouses. Growth Chambers are small (3m x 4/m and smaller) walk-in or reach-in enclosures with programmable, accurate temperature, relative humidity (RH) and irradiance control over wide ranges. The intent of growth chambers was to replicate sunlight conditions and transfer research results directly to the greenhouse or outside. It was realized that sunlight and outside conditions could not be mimicked. Growth chambers are also used to study irradiance and spectral fluxes. Growth Rooms are usually large rooms (larger than 3m x 4m) with only lamp irradiance, but providing relatively limited ranges of environmental control (i.e., 10 to 30 C temperature, 50 to 90% RH and ambient to 1000 ppm CO{sub 2}), and commonly independent of outside conditions. Irradiance requirements for growth rooms are similar to those of growth chambers. Growth rooms are also used for growing a large number of plants in a uniform standard environment condition and in commercial horticulture for tissue culture, seed germination (plugs) and seedling growth. Greenhouses are designed to allow maximum sunlight penetration through the structure. Initially greenhouses were used to extend the growing season. Then as heating systems, and cooling systems improved, they were used year round. Low light during the winter months reduced plant growth, but with the advent of efficient lamps (HID and fluorescent) it became possible to increase growth to rates close to that in summer months. Supplementary lighting is used during low light periods of the year and anytime to ensure consistent total daily irradiance for research plants.

  8. Diffuse mode and diffuse-to-filamentary transition in a high pressure nanosecond scale corona discharge under high voltage

    Science.gov (United States)

    Tardiveau, P.; Moreau, N.; Bentaleb, S.; Postel, C.; Pasquiers, S.

    2009-09-01

    The dynamics of a point-to-plane corona discharge induced in high pressure air under nanosecond scale high overvoltage is investigated. The electrical and optical properties of the discharge can be described in space and time with fast and precise current measurements coupled to gated and intensified imaging. Under atmospheric pressure, the discharge exhibits a diffuse pattern like a multielectron avalanche propagating through a direct field ionization mechanism. The diffuse regime can exist since the voltage rise time is much shorter than the characteristic time of the field screening effects, and as long as the local field is higher than the critical ionization field in air. As one of these conditions is not fulfilled, the discharge turns into a multi-channel regime and the diffuse-to-filamentary transition strongly depends on the overvoltage, the point-to-plane gap length and the pressure. When pressure is increased above atmospheric pressure, the diffuse stage and its transition to streamers seem to satisfy similarity rules as the key parameter is the reduced critical ionization field only. However, above 3 bar, neither diffuse avalanche nor streamer filaments are observed but a kind of streamer-leader regime, due to the fact that mechanisms such as photoionization and heat diffusion are not similar to pressure.

  9. Rating curve estimation using local stages, upstream discharge data and a simplified hydraulic model

    Directory of Open Access Journals (Sweden)

    M. Franchini

    1999-01-01

    Full Text Available This article proposes a methodology for synthesising the rating curve in one or more cross-sections of a watercourse provided with stage data, when a reliable rating curve and stage data are also available in the upstream cross-section; the synthesised rating curves are consistent with each other. The proposed methodology uses a variable parameter Muskingum-Cunge model whose parameters take express account of travel times and attenuation of the flood wave, and are expressed in such a way that allows for an integration in the time-space domain even when a topographic survey of the river is not available. Furthermore, the methodology proposed implicitly provides a ready-calibrated simulation model whose ease of application suggests that it could also be useful in real time stage forecasting. The paper includes a description of a numerical application to a reach of the Po River (Italy.

  10. High strain rate behaviour of polypropylene microfoams

    Directory of Open Access Journals (Sweden)

    Martínez A.B.

    2012-08-01

    Full Text Available Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc. or personal safety (helmets, knee-pads, etc.. In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000 s−1 in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB. Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

  11. High strain rate behaviour of polypropylene microfoams

    Science.gov (United States)

    Gómez-del Río, T.; Garrido, M. A.; Rodríguez, J.; Arencón, D.; Martínez, A. B.

    2012-08-01

    Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc.) or personal safety (helmets, knee-pads, etc.). In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry) is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000 s-1) in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB). Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

  12. 38 CFR 4.28 - Prestabilization rating from date of discharge from service.

    Science.gov (United States)

    2010-07-01

    ... ratings prescribed elsewhere, under the conditions stated for disability from any disease or injury. The...— Substantially gainful employment is not feasible or advisable 100 Unhealed or incompletely healed wounds or injuries— Material impairment of employability likely 50 Note (1): Department of Veterans Affairs...

  13. Fowl play? Forensic environmental assessment of alleged discharge of highly contaminated effluent from a chicken slaughterhouse

    Science.gov (United States)

    Harvey, P.; Taylor, M. P.; Handley, H. K.

    2016-12-01

    Multiple lines of geochemical and biological evidence are applied to identify and fingerprint the nature and source of alleged contamination emanating from a chicken slaughterhouse on the urban fringe of Sydney, Australia. The slaughterhouse has a long history of alleged environmental misconduct. The impact of the facility on catchment source waters by the slaughterhouse has been the subject of controversy. The facility owner has persistently denied breach of their licence condition and maintains it is `a very environmentally conscious operation'. The disputed nature of the possible sources of discharges and its contaminants required a detailed forensic environmental assessment. Water samples collected from off-site discharge points associated with the facility show highly elevated concentrations of faecal coliforms (max 68,000 cfu), ammonia-N (51,000 µg/L), total nitrogen (98,000 µg/L) and phosphorous (32,000 µg/L). Upstream and adjacent watercourses were markedly less contaminated. Water discharge points associated with the slaughterhouse and natural catchment runoff were sampled for arsenic speciation, including assessment for the organoarsenic compound Roxarsone. Roxarsone is used as a chicken growth promoter. Water draining the slaughterhouse facility contained concentrations around 10 times local background levels. The Roxarsone compound was not detected in any waters, but inorganic arsenic, As(V), was present in all waters with the greatest concentrations in waters draining from the slaughterhouse. The environmental evidence was compiled over a series of discharges events and presented to the NSW EPA. Subsequent to receipt of the data supported by their own investigations, the NSW EPA mandated that the slaughterhouse be subject to a pollution reduction program. The efficacy of the pollution reduction program to stem the release of highly contaminated effluent is currently subject to ongoing investigation using a suite of water chemistry measures including

  14. Thermal regime of self-heated hollow cathode in a low-pressure high-current pulsed-periodic discharge

    Science.gov (United States)

    Gavrilov, N. V.; Emlin, D. R.

    2017-11-01

    We have studied the thermal regime of a self-heated hollow cathode in combined low-current (1-5 A) dc discharge and high-current (up to 100 A) pulsed-periodic discharge and the influence of the pulsed parameters on the current-voltage characteristic of the high-current discharge. It has been shown that, after the application of a voltage pulse (200-500 V), the discharge current attains its peak value and is stabilized over a time of 100 μs. The discharge voltage in the quasi-stationary discharge stage exceeds the continuous discharge voltage at the same current by many times and depends on the mean value of the current in the discharge gap. The interpretation of the form of the I-V characteristics of the pulsed discharge is based on the dynamics of heating and cooling of the cathode surface layer and on the variations in the integral temperature of the cathode.

  15. Hydrodynamic modelling of transient cavities in fluids generated by high voltage spark discharges

    Energy Technology Data Exchange (ETDEWEB)

    Timoshkin, I V; Fouracre, R A; Given, M J; MacGregor, S J [HVT Research Group, Institute for Energy and Environment, Department of Electronic and Electrical Engineering, University of Strathclyde, Royal College Building, 204 George St, Glasgow, G1 1XW (United Kingdom)

    2006-11-21

    Application of a voltage pulse having a rise time of tens of nanoseconds to electrodes immersed in water results in streamer development and the formation of a highly conductive plasma channel between the electrodes. The electrical resistance of such channels decreases rapidly from a few ohms to a few tens of milliohms due to Joule heating resulting from the high current which flows through the plasma. The dynamics of the plasma resistance depend on the parameters of the discharge circuit and the medium in which the discharge takes place. The resistance of the channel reaches a minimum value approximately at the moment of the peak current for under-damped current oscillations. During the resistance collapse, the pressure inside the channel rises to several GPa, causing a rapid expansion of the channel which forms a cavity in the liquid resulting in a high power ultrasound pulse. The cavity expands to a maximum size which is dependent on the circuit driving the discharge and the properties of the plasma discharge channel. The cavity then collapses producing a second acoustic pulse. In this paper the dynamic resistance of the spark channel is described using a phenomenological model based on the plasma channel energy balance equation used by Braginskii. The model which links the hydrodynamic characteristics of the channel and the resulting cavity with the parameters of the electric driving circuit allows the development of the plasma channel and cavity to be predicted. The peak high-power ultrasound (HPU) pressures calculated using this approach are compared with the pressure values estimated by an analytical model which uses a constant value of the spark channel resistance derived from experimental data. Comparisons are also made with direct measurements of HPU output made using a Pinducer sensor. Although the model is based on a phenomenological description of the plasma channel dynamics and its resistance and requires the value of the spark constant, the results

  16. Hydrodynamic modelling of transient cavities in fluids generated by high voltage spark discharges

    Science.gov (United States)

    Timoshkin, I. V.; Fouracre, R. A.; Given, M. J.; MacGregor, S. J.

    2006-11-01

    Application of a voltage pulse having a rise time of tens of nanoseconds to electrodes immersed in water results in streamer development and the formation of a highly conductive plasma channel between the electrodes. The electrical resistance of such channels decreases rapidly from a few ohms to a few tens of milliohms due to Joule heating resulting from the high current which flows through the plasma. The dynamics of the plasma resistance depend on the parameters of the discharge circuit and the medium in which the discharge takes place. The resistance of the channel reaches a minimum value approximately at the moment of the peak current for under-damped current oscillations. During the resistance collapse, the pressure inside the channel rises to several GPa, causing a rapid expansion of the channel which forms a cavity in the liquid resulting in a high power ultrasound pulse. The cavity expands to a maximum size which is dependent on the circuit driving the discharge and the properties of the plasma discharge channel. The cavity then collapses producing a second acoustic pulse. In this paper the dynamic resistance of the spark channel is described using a phenomenological model based on the plasma channel energy balance equation used by Braginskii. The model which links the hydrodynamic characteristics of the channel and the resulting cavity with the parameters of the electric driving circuit allows the development of the plasma channel and cavity to be predicted. The peak high-power ultrasound (HPU) pressures calculated using this approach are compared with the pressure values estimated by an analytical model which uses a constant value of the spark channel resistance derived from experimental data. Comparisons are also made with direct measurements of HPU output made using a Pinducer sensor. Although the model is based on a phenomenological description of the plasma channel dynamics and its resistance and requires the value of the spark constant, the results

  17. Origins of ion energy distribution function (IEDF) in high power impulse magnetron sputtering (HIPIMS) plasma discharge

    Science.gov (United States)

    Hecimovic, A.; Burcalova, K.; Ehiasarian, A. P.

    2008-05-01

    The ion energy distribution function (IEDF) in high power impulse magnetron sputtering (HIPIMS) discharges was studied by plasma sampling energy-resolved mass spectroscopy. HIPIMS of chromium (Cr), titanium (Ti) and carbon (C) targets in argon (Ar) atmosphere was analysed. Singly and doubly charged ions of both the target and the gas were detected. Time-averaged IEDFs were measured for all detected ions at the substrate position at a distance of 150 mm from the target. The effects of target current and discharge pressure on the IEDF were investigated. Measurements were done at two pressures and for three peak discharge currents. The IEDF of both the target and the gas ions was found to comprise two Maxwellian distributions. Quantitative analysis of target IEDFs at a low pressure showed that the main peak had a lower average energy with an approximate value of EAV = 1 eV which is attributed to collisions with thermalized gas atoms and ions. The higher energy distribution has a tail extending up to 70 eV, which is assumed to originate from a Thompson distribution of sputtered metal atoms which, due to collisions, are thermalized and appear as a Maxwell distribution. The proportion of high energy IEDFs for metal ions increases monotonically as a function of Id. The effective ion temperature kBT, extracted from the main low energy peak, showed a weak dependence on peak current. The effective ion temperature extracted from the high energy tail showed a strong correlation with the change in Id. The IEDF at high pressure shows that a proportion of high energy IEDFs was very low and dominated by a low energy main peak. The gas IEDF at high pressure was completely thermalized. The metal-ion-to-gas-ion ratio was found to increase with Id and with the sputtering yield of the target material.

  18. High intensity discharge 400-watt sodium ballast. Phase I. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Felper, G.

    1980-06-01

    The results of a research and development program directed toward design, test, and evaluation of energy efficient High Intensity Discharge (HID) Solid State 400-Watt Ballast lighting system are reported. Phase I of the project which was designed to modify the existing Datapower ballast to LBL configuration, measure performance characteristics, and compare efficiency with a core/coil ballast including energy loss analysis is covered. In addition, Datapower was tasked to build six (6) prototype 400-Watt High Pressure Sodium Ballasts for verification tests by an independent test facility and follow-on performance and life tests at LBL.

  19. Discharge instabilities in high-pressure helium-fluorine laser gas mixtures

    NARCIS (Netherlands)

    Mathew, D.; Bastiaens, Hubertus M.J.; Peters, P.J.M.; Boller, Klaus J.

    2005-01-01

    Discharge instabilities in F2 based excimer gas lasers are investigated using a small-scale discharge system. After preionizing the gas volume, a fast rising voltage pulse initiates the discharge. The temporal development of the discharge is monitored via its fluorescence by an intensified CCD

  20. Analysis of experimental routines of high enthalpy steam discharge in subcooled water

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco, Rafael R., E-mail: Rafael.rade@ctmsp.mar.mil.br [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), SP (Brazil); Andrade, Delvonei A., E-mail: delvonei@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    The discharge of high enthalpy steam through safety release valves out from pressurizers in PWR's needs to be condensed in order to allow the treatment of possibly present radwaste within. The Direct Contact Condensation is used in a relief tank to achieve the condensation. Care must be taken to avoid the bypass of the steam through the subcooled water, what would increase the peak of pressure and the necessity of structural reinforcement of the relief tank. An experiment to determine the optimal set up of the relief tank components and their characteristics (type of sprinkler, level of water, volume of tank, discharge direction, pressure in the pressurizer among others) was executed in 2000, in the CTE 150 facility, in CTMSP. In a total, 144 routines varying its components and characteristics were made, although no comprehensive analysis of its results were yet made, since the mass of data was too big to be readily analyzed. In order to comprehensively analyze it, a VBA program is being made to compile and graphically represent the mass of data. The current state of this program allowed conclusions over the peak pressure, adiabatic assumption of the experiment, and the quality of the steam generated due to the discharge. (author)

  1. Optical investigations of high pressure glow discharges based on MSE arrays

    Energy Technology Data Exchange (ETDEWEB)

    Penache, C.; Hohn, O.; Schmidt-Boecking, H. [Frankfurt Univ. (Germany); Spielberger, L. [Deutsche Gesellschaft fuer Technische Zusammenarbeit GmbH (GTZ), Eschborn (Germany); Braeuning-Demian, A.; Penache, D. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)

    2001-07-01

    The micro-structure-electrode (MSE) arrays are providing a non-thermal high pressure plasma. These arrays consist of a matrix of holes perforated in a thin multilayer made out of two metallic foils separated by a dielectric. The holes diameter and the thickness of the insulator spacer need to be around 100 {mu}m to allow for the MSE operation at pressure ranging from 0.1 to 1 bar and above. In this work single direct current microdischarges and systems of parallel operated holes in argon at 0.2 bar have been optically investigated. The spatial distribution of the emitted light has been monitored by a digital camera connected to an optical microscope. The UV photon emission has been recorded by a position sensitive photon detector allowing for space and time resolved measurements. Its time resolution of about 1 nsec makes possible the investigation of fast processes, e.g. the constriction of the discharge. Due to its typical position resolution of 100 {mu}m, this detector needs to be used in combination with an optical system allowing for the magnification of the discharge area. The optical appearance show a stable, volume filling glow discharge, fact proved also by the typical current-voltage characteristic.

  2. Two-step ionization in non-equilibrium SF sub 6 discharges at high current density

    CERN Document Server

    Bychkov, Yu A; Lacour, B; Pasquiers, S; Puech, V; Yastremski, A

    2003-01-01

    In the pressure range 10-100 mbar, the discharge development in SF sub 6 has been investigated in the photo-triggered excitation scheme for current density in the range 10-1000 A cm sup - sup 2 and pulse duration of about 60 ns. Thanks to the homogeneity of the photo-triggered discharge, a self-consistent zero-dimensional model can be used to predict the temporal evolution of the electrical parameters. From a detailed comparison between the experimental results and the modelling predictions, evidence for the occurrence of a two-step ionization process in high current density discharges in SF sub 6 is reported and the corresponding collision cross-section is estimated. Moreover, it is shown that the amount of the two-step ionization is directly correlated to the density of the electrical charge transferred to the plasma per unit surface. This two-step ionization becomes the main source of electron multiplication whenever the transferred charge per unit surface is higher than 15 mu C cm sup - sup 2.

  3. A high-current rail-type gas switch with preionization by an additional corona discharge

    Energy Technology Data Exchange (ETDEWEB)

    Antipov, E. I.; Belozerov, O. S.; Krastelev, E. G., E-mail: ekrastelev@yandex.ru [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) (Russian Federation)

    2016-12-15

    The characteristics of a high-current rail-type gas switch with preionization of the gas (air) in a spark gap by an additional corona discharge are investigated. The experiments were performed in a voltage range of 10–45 kV using a two-electrode switch consisting of two cylindrical electrodes with a diameter of 22 mm and a length of 100 mm and a set of laterally located corona-discharge needles. The requirements for the position and size of the needles are defined for which a corona discharge is ignited before a breakdown of the main gap and does not change to a sparking form, and the entire length of the rail electrodes is efficiently used. The fulfillment of these requirements ensures stable operation of the switch with a small variation of the pulse breakdown voltage, which is not more than 1% for a fixed voltage-pulse rise time in the range from 150 ns to 3.5 μs. A short delay time of the switch breakdown makes it possible to control the two-electrode switch by an overvoltage pulse of nanosecond duration.

  4. High-speed sterilization technique using dielectric barrier discharge plasmas in atmospheric humid air

    Science.gov (United States)

    Miyamae, M.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

    2010-11-01

    The inactivation of Bacillus atrophaeus spores by a dielectric barrier discharge (DBD) plasma produced by an ac voltage application of 1 kHz in atmospheric humid air was investigated in order to develop low-temperature, low-cost and high-speed plasma sterilization technique. The biological indicators covered with a Tyvek sheet were set just outside the DBD plasma region, where the air temperature and humidity as a discharge gas were precisely controlled by an environmental test chamber. The results show that the inactivation of Bacillus atrophaeus spores was found to be dependent strongly on the humidity, and was completed within 15 min at a relative humidity of 90 % and a temperature of 30 C. The treatment time for sterilization is shorter than those of conventional sterilization methods using ethylene oxide gas and dry heat treatment. It is considered that reactive species such as hydroxyl radicals that are effective for the inactivation of Bacillus atrophaeus spores could be produced by the DBD plasma in the humid air. Repetitive micro-pulsed discharge plasmas in the humid air will be applied for the sterilization experiment to enhance the sterilization efficiency.

  5. Experimental Study of Material Removal Rate in Electrical Discharge Turning of Titanium Alloy (Ti-6al-4v)

    Science.gov (United States)

    Puri, Y. M.; Gohil, Vikas

    2017-03-01

    Electrical discharge turning (EDT) is a new machining process in which an external axis is added to a conventional EDM machine in order to produce precise cylindrical forms on hard and difficult to machine materials. By feeding a pre shaped tool electrode against a rotating work piece, axially symmetrical pats can be produce. The machining performance of EDT process is influenced by its machining parameters, which directly affect the quality of the machined component. This paper presents an experimental study on the effects of EDM parameters namely pulse-on time, peak current, gap voltage, spindle speed and flushing pressure on material removal rate (MRR) in electrical discharge turning of titanium alloy Ti-6Al-4V. This has been done by means of the Taguchi’s design of experiment technique. A mathematical model has been developed for MRR by regression analysis and factor effects were analyzed using analysis of variance (ANOVA). Signal-to-noise ratio analysis is used to find the optimal condition.

  6. Experimental investigation and simulation of temperature distributions in a 16Ah-LiMnNiCoO2 battery during rapid discharge rates

    Science.gov (United States)

    Panchal, S.; Dincer, I.; Agelin-Chaab, M.; Fraser, R.; Fowler, M.

    2017-03-01

    It is very important to have quantitative data regarding the temperature distributions of lithium-ion batteries at different discharge rates in order to design thermal management systems and also for battery thermal modellers. In this paper, the surface temperature distributions on a superior lithium polymer battery (SLPB) with lithium manganese nickel cobalt oxide (LiMnNiCoO2) cathode material (16 Ah capacity) at C/8, C/4, C/2, 1C, 2C, and 3C discharge rates are presented. Additionally, a battery thermal model is developed for this battery using a neural network approach with the Bayesian Regularization method and the simulated results are compared with experimental results in terms of temperature and voltage profiles at C/8, C/4, C/2, 1C, 2C, and 3C discharge rates. Thermal images, which were also captured during experiments with an IR camera at various discharge rates, and are reported in the paper. The results of this study show that the increased discharge rates between C/8 and 3C results in increased surface temperature distributions on the principal surface of the battery and decreased discharge capacity.

  7. Variation in rates of ICU readmissions and post-ICU in-hospital mortality and their association with ICU discharge practices.

    Science.gov (United States)

    van Sluisveld, Nelleke; Bakhshi-Raiez, Ferishta; de Keizer, Nicolette; Holman, Rebecca; Wester, Gert; Wollersheim, Hub; van der Hoeven, Johannes G; Zegers, Marieke

    2017-04-17

    Variation in intensive care unit (ICU) readmissions and in-hospital mortality after ICU discharge may indicate potential for improvement and could be explained by ICU discharge practices. Our objective was threefold: (1) describe variation in rates of ICU readmissions within 48 h and post-ICU in-hospital mortality, (2) describe ICU discharge practices in Dutch hospitals, and (3) study the association between rates of ICU readmissions within 48 h and post-ICU in-hospital mortality and ICU discharge practices. We analysed data on 42,040 admissions to 82 (91.1%) Dutch ICUs in 2011 from the Dutch National Intensive Care Evaluation (NICE) registry to describe variation in standardized ICU readmission and post-ICU mortality rates using funnel-plots. We send a questionnaire to all Dutch ICUs. 75 ICUs responded and their questionnaire data could be linked to 38,498 admissions in the NICE registry. Generalized estimation equations analyses were used to study the association between ICU readmissions and post-ICU mortality rates and the identified discharge practices, i.e. (1) ICU discharge criteria; (2) bed managers; (3) early discharge planning; (4) step-down facilities; (5) medication reconciliation; (6) verbal and written handover; (7) monitoring of post-ICU patients; and (8) consulting ICU nurses. In all analyses, the outcomes were corrected for patient-related confounding factors. The standardized rate of ICU readmissions varied between 0.14 and 2.67 and 20.8% of the hospitals fell outside the 95% control limits and 3.6% outside the 99.8% control limits. The standardized rate of post-ICU mortality varied between 0.07 and 2.07 and 17.1% of the hospitals fell outside the 95% control limits and 4.9% outside the 99.8% control limits. We could not demonstrate an association between the eight ICU discharge practices and rates of ICU readmissions or post-ICU in-hospital mortality. Implementing a higher number of ICU discharge practices was also not associated with better

  8. On-line Monitoring Device for High-voltage Switch Cabinet Partial Discharge Based on Pulse Current Method

    Science.gov (United States)

    Y Tao, S.; Zhang, X. Z.; Cai, H. W.; Li, P.; Feng, Y.; Zhang, T. C.; Li, J.; Wang, W. S.; Zhang, X. K.

    2017-12-01

    The pulse current method for partial discharge detection is generally applied in type testing and other off-line tests of electrical equipment at delivery. After intensive analysis of the present situation and existing problems of partial discharge detection in switch cabinets, this paper designed the circuit principle and signal extraction method for partial discharge on-line detection based on a high-voltage presence indicating systems (VPIS), established a high voltage switch cabinet partial discharge on-line detection circuit based on the pulse current method, developed background software integrated with real-time monitoring, judging and analyzing functions, carried out a real discharge simulation test on a real-type partial discharge defect simulation platform of a 10KV switch cabinet, and verified the sensitivity and validity of the high-voltage switch cabinet partial discharge on-line monitoring device based on the pulse current method. The study presented in this paper is of great significance for switch cabinet maintenance and theoretical study on pulse current method on-line detection, and has provided a good implementation method for partial discharge on-line monitoring devices for 10KV distribution network equipment.

  9. High strain rate deformation of layered nanocomposites

    Science.gov (United States)

    Lee, Jae-Hwang; Veysset, David; Singer, Jonathan P.; Retsch, Markus; Saini, Gagan; Pezeril, Thomas; Nelson, Keith A.; Thomas, Edwin L.

    2012-11-01

    Insight into the mechanical behaviour of nanomaterials under the extreme condition of very high deformation rates and to very large strains is needed to provide improved understanding for the development of new protective materials. Applications include protection against bullets for body armour, micrometeorites for satellites, and high-speed particle impact for jet engine turbine blades. Here we use a microscopic ballistic test to report the responses of periodic glassy-rubbery layered block-copolymer nanostructures to impact from hypervelocity micron-sized silica spheres. Entire deformation fields are experimentally visualized at an exceptionally high resolution (below 10 nm) and we discover how the microstructure dissipates the impact energy via layer kinking, layer compression, extreme chain conformational flattening, domain fragmentation and segmental mixing to form a liquid phase. Orientation-dependent experiments show that the dissipation can be enhanced by 30% by proper orientation of the layers.

  10. PIEZOELECTRIC WAVEGUIDE SENSOR FOR MEASURING PULSE PRESSURE IN CLOSED LIQUID VOLUMES AT HIGH VOLTAGE ELECTRIC DISCHARGE

    Directory of Open Access Journals (Sweden)

    V. G. Zhekul

    2017-10-01

    Full Text Available Purpose. Investigations of the characteristics of pressure waves presuppose the registration of the total profile of the pressure wave at a given point in space. For these purposes, various types of «pressure to the electrical signal» transmitters (sensors are used. Most of the common sensors are unsuitable for measuring the pulse pressure in a closed water volume at high hydrostatic pressures, in particular to study the effect of a powerful high-voltage pulse discharge on increasing the inflow of minerals and drinking water in wells. The purpose of the work was to develop antijamming piezoelectric waveguide sensor for measuring pulse pressure at a close distance from a high-voltage discharge channel in a closed volume of a liquid. Methodology. We have applied the calibration method as used as a secondary standard, the theory of electrical circuits. Results. We have selected the design and the circuit solution of the waveguide pressure sensor. We have developed a waveguide pulse-pressure sensor DTX-1 with a measuring loop. This sensor makes it possible to study the spectral characteristics of pressure waves of high-voltage pulse discharge in closed volumes of liquid at a hydrostatic pressure of up to 20 MPa and a temperature of up to 80 °C. The sensor can be used to study pressure waves with a maximum amplitude value of up to 150 MPa and duration of up to 80 µs. According to the results of the calibration, the sensitivity of the developed sensor DTX-1 with a measuring loop is 0.0346 V/MPa. Originality. We have further developed the theory of designing the waveguide piezoelectric pulse pressure sensors for measuring the pulse pressure at a close distance from a high-voltage discharge channel in a closed fluid volume by controlling the attenuation of the amplitude of the pressure signal. Practical value. We have developed, created, calibrated, used in scientific research waveguide pressure pulse sensors DTX-1. We propose sensors DTX-1 for sale

  11. A method for simultaneous estimation of groundwater evapotranspiration and inflow rates in the discharge area using seasonal water table fluctuations

    Science.gov (United States)

    Jiang, Xiao-Wei; Sun, Zhi-Chao; Zhao, Ke-Yu; Shi, Fu-Sheng; Wan, Li; Wang, Xu-Sheng; Shi, Zhe-Ming

    2017-05-01

    As an indispensable component of groundwater circulation, groundwater evapotranspiration rate (ETG) estimation using water table fluctuations is a hot research topic in the past decades. However, most existing methods for estimating ETG using either diurnal or seasonal water table fluctuations are based on the assumptions that groundwater recharge equals 0 in the whole period and ETG equals 0 in a specific duration of time. The aim of the current study is to develop a method to estimate ETG when both assumptions do not apply. In the discharge area of a semi-arid catchment in the Ordos Plateau, NW China, it is found out that the water table fluctuations are influenced greatly by recharge, ETG and the vertical inflow rate (qin) in the seasonal scale but are controlled by atmospheric pressure instead of evapotranspiration in the diurnal scale, which implies that the existing methods are not applicable. Therefore, we propose a method to estimate ETG and qin using the seasonal water table fluctuations based on the assumptions that qin is stable throughout the year and ETG has a linear relationship to the reference evapotranspiration (ET0). It is found out that qin is around 1.12 mm/d, and the ratio of ETG to ET0 is around 0.4. ETG in April through July with the highest ET0 of the year is found to be around 3 mm/d, which is much larger than qin, thus leads to significant decline in water table. ETG in November with the lowest ET0 of the unfrozen period is found to be 1.0 mm/d, which is slightly smaller than qin, thus results in a weak increase in water table. The vertical component of regional groundwater inflow is found to exceed precipitation recharge, indicating that regional groundwater inflow plays the major role on maintaining the shallow water table in the discharge area. Groundwater evapotranspiration is also found to exceed precipitation recharge in most time of the unfrozen period, indicating a specified-flux upper boundary with water loss in the discharge area

  12. Continuous point-like high-temperature laser discharge produced by terahertz free electron laser

    Directory of Open Access Journals (Sweden)

    V. V. Kubarev

    2017-09-01

    Full Text Available A continuous point-like laser discharge of record high temperature has been produced in argon at atmospheric pressure with focusing of the radiation of the Novosibirsk terahertz free electron laser (NovoFEL. According to spectral measurements, the temperature in the center of the millimeter-sized plasma sphere was 28000 K at a plasma density of 1.5×1017 cm-3 and an average NovoFEL power of 200 W at a wavelength of 130 μm (2.3 THz.

  13. The pain-induced decrease in low-threshold motor unit discharge rate is not associated with the amount of increase in spike-triggered average torque.

    Science.gov (United States)

    Farina, Dario; Arendt-Nielsen, Lars; Roatta, Silvestro; Graven-Nielsen, Thomas

    2008-01-01

    Activation of nociceptive afferents decreases motor unit discharge rates in static contractions. There is also evidence that during experimental muscle pain the motor unit twitch force increases, which has been hypothesized to compensate for the decrease in discharge rate to maintain constant force. This study examined whether there is an association between the magnitude of change in motor unit discharge rate and the amount of increase in the spike-triggered average torque during experimental muscle pain. Sixteen subjects performed three constant-torque isometric ankle dorsi-flexions at 10% of the maximal force (MVC) alternated with two contractions at constant discharge rate of a target motor unit, before and following injection of 0.5 ml of hypertonic (painful) or isotonic (control) saline into the tibialis anterior muscle. The discharge rate of the target unit at 10% MVC decreased following injection of hypertonic saline (P<0.05; mean+/-SD, before: 9.9+/-1.3 pulses per second, pps; after injection: 8.9+/-1.0 pps). The peak of the spike-triggered average torque increased with pain (P<0.05; before: 0.56+/-0.55 mNm; during pain: 0.95+/-1.02 mNm) but the increase was not correlated with the decrease in discharge rate (R=0.08). Propagation velocity and action potential peak-to-peak amplitude did not change with pain. The pain-induced modifications in the estimated motor unit twitch torque (1) were not caused by changes in muscle fiber action potential, and (2) were not associated with the decrease in discharge rate. Maintenance of constant force during static painful contractions is not explained by a matching between changes in contractile and control motor unit properties.

  14. High dose rate brachytherapy for oral cancer

    Science.gov (United States)

    YamazakI, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Furukawa, Souhei; Koizumi, Masahiko; Ogawa, Kazuhiko

    2013-01-01

    Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer. PMID:23179377

  15. Lighting Systems For High Speed Photography Applying Special Metal Halide Discharge Lamps

    Science.gov (United States)

    Gillum, Keith M.; Steuernagel, K. H.

    1983-03-01

    High speed photography requires, in addition to a good color quality of the light source, a very high level of illumination. Conventional lighting systems utilizing incandescent lamps or other metal halide lamp types has inherent problems of inefficient light output or poor color quality. Heat generated by incandescent lamps and the power these sources require drive up operating and installation costs. A most economical and practical solution was devised by using the metal halide discharge lamp developed by OSRAM, GmbH of Munich, West Germany. This lamp trade marked the HMITM Metallogen was primarily developed for the needs of the television and motion picture film industry. Due to their high efficiency and other consistent operating qualities these lamps also fulfill the needs of high speed photography, e.g. in crash test facilities, when special engineering activities are carried out. The OSRAM HMITM lamp is an AC discharge metal halide lamp with rare earth additives to increase both the efficiency and light output qualities. Since the lamp is an AC source, a special method had to be developed to overcome the strobing effect, which is normal for AC lamps given their modulated light output, when used with high speed cameras, (e.g. with >1000 fps). This method is based on an increased frequency for the lamp supply voltage coupled with a mix of the light output achieved using a multiphase mains power supply. First developed in 1977, this system using the OSRAM HMITM lamps was installed in a crash test facility of a major automotive manufacturer in West Germany. The design resulted in the best lighting and performance ever experienced. Since that time several other motor companies have made use of this breakthrough. Industrial and scientific users are now considering additional applications use of this advanced high speed lighting system.

  16. High-resolution water column survey to identify active sublacustrine hydrothermal discharge zones within Lake Rotomahana, North Island, New Zealand

    Science.gov (United States)

    Walker, Sharon L.; de Ronde, Cornel E. J.; Fornari, Daniel; Tivey, Maurice A.; Stucker, Valerie K.

    2016-03-01

    Autonomous underwater vehicles were used to conduct a high-resolution water column survey of Lake Rotomahana using temperature, pH, turbidity, and oxidation-reduction potential (ORP) to identify active hydrothermal discharge zones within the lake. Five areas with active sublacustrine venting were identified: (1) the area of the historic Pink Terraces; (2) adjacent to the western shoreline subaerial "Steaming Cliffs," boiling springs and geyser; (3) along the northern shoreline to the east of the Pink Terrace site; (4) the newly discovered Patiti hydrothermal system along the south margin of the 1886 Tarawera eruption rift zone; and (5) a location in the east basin (northeast of Patiti Island). The Pink Terrace hydrothermal system was active prior to the 1886 eruption of Mount Tarawera, but venting along the western shoreline, in the east basin, and the Patiti hydrothermal system appear to have been initiated in the aftermath of the eruption, similar to Waimangu Valley to the southwest. Different combinations of turbidity, pH anomalies (both positive and negative), and ORP responses suggest vent fluid compositions vary over short distances within the lake. The seasonal period of stratification limits vertical transport of heat to the surface layer and the hypolimnion temperature of Lake Rotomahana consequently increases with an average warming rate of ~ 0.010 °C/day due to both convective hydrothermal discharge and conductive geothermal heating. A sudden temperature increase occurred during our 2011 survey and was likely the response to an earthquake swarm just 11 days prior.

  17. High-energy, high-rate materials processing

    Science.gov (United States)

    Marcus, H. L.; Bourell, D. L.; Eliezer, Z.; Persad, C.; Weldon, W.

    1987-12-01

    The increasingly available range of pulsed-power, high energy kinetic storage devices, such as low-inductance pulse-forming networks, compulsators, and homopolar generators, is presently considered as a basis for industrial high energy/high rate (HEHR) processing to accomplish shock hardening, drilling, rapid surface alloying and melting, welding and cutting, transformation hardening, and cladding and surface melting in metallic materials. Time-temperature-transformation concepts furnish the basis for a fundamental understanding of the potential advantages of this direct pulsed power processing. Attention is given to the HEHR processing of a refractory molybdenum alloy, a nickel-base metallic glass, tungsten, titanium aluminides, and metal-matrix composites.

  18. Operation of high rate microstrip gas chambers

    CERN Document Server

    Barr, A J; Bouclier, Roger; Capéans-Garrido, M; Dominik, Wojciech; Manzin, G; Million, Gilbert; Hoch, M; Ropelewski, Leszek; Sauli, Fabio; Sharma, A

    1996-01-01

    We describe recent measurements carried out in well controlled and reproducible conditions to help understanding the factors affecting the short and long term behaviour of Microstrip Gas Chambers. Special care has been taken concerning the gas purity and choice of materials used in the system and for the detectors construction. Detectors built on glasses with surface resistivity in the range $10^{13}-10^{15} \\Omega/\\Box$ have shown satisfactory performance as they do not show charging-up process at high rate and stand the large doses required for the future high luminosity experiments (~10 mC·cm-1·yr-1). Concerning the lifetime measurements, it has been observed that chambers manufactured on high-resistivity glass are far more susceptible of suffering ageing than detectors made on low resistivity, electron-conducting supports, independently of the metal used for the artwork (chromium or gold) at least in clean gas conditions. The successfully operation in the laboratory of detectors manufactured on diamond-...

  19. Prediction of material removal rate and surface roughness for wire electrical discharge machining of nickel using response surface methodology

    Directory of Open Access Journals (Sweden)

    Thangam Chinnadurai

    2016-12-01

    Full Text Available This study focuses on investigating the effects of process parameters, namely, Peak current (Ip, Pulse on time (Ton, Pulse off time (Toff, Water pressure (Wp, Wire feed rate (Wf, Wire tension (Wt, Servo voltage (Sv and Servo feed setting (Sfs, on the Material Removal Rate (MRR and Surface Roughness (SR for Wire electrical discharge machining (Wire-EDM of nickel using Taguchi method. Response Surface Methodology (RSM is adopted to evolve mathematical relationships between the wire cutting process parameters and the output variables of the weld joint to determine the welding input parameters that lead to the desired optimal wire cutting quality. Besides, using response surface plots, the interaction effects of process parameters on the responses are analyzed and discussed. The statistical software Mini-tab is used to establish the design and to obtain the regression equations. The developed mathematical models are tested by analysis-of-variance (ANOVA method to check their appropriateness and suitability. Finally, a comparison is made between measured and calculated results, which are in good agreement. This indicates that the developed models can predict the responses accurately and precisely within the limits of cutting parameter being used.

  20. Synergetic aspects of gas-discharge: lateral patterns in dc systems with a high ohmic barrier

    Science.gov (United States)

    Purwins, H.-G.; Stollenwerk, L.

    2014-12-01

    The understanding of self-organized patterns in spatially extended nonlinear dissipative systems is one of the most challenging subjects in modern natural sciences. Such patterns are also referred to as dissipative structures. We review this phenomenon in planar low temperature dc gas-discharge devices with a high ohmic barrier. It is demonstrated that for these systems a deep qualitative understanding of dissipative structures can be obtained from the point of view of synergetics. At the same time, a major contribution can be made to the general understanding of dissipative structures. The discharge spaces of the experimentally investigated systems, to good approximation, have translational and rotational symmetry by contraction. Nevertheless, a given system may exhibit stable current density distributions and related patterns that break these symmetries. Among the experimentally observed fundamental patterns one finds homogeneous isotropic states, fronts, periodic patterns, labyrinth structures, rotating spirals, target patterns and localized filaments. In addition, structures are observed that have the former as elementary building blocks. Finally, defect structures as well as irregular patterns are common phenomena. Such structures have been detected in numerous other driven nonlinear dissipative systems, as there are ac gas-discharge devices, semiconductors, chemical solutions, electrical networks and biological systems. Therefore, from the experimental observations it is concluded that the patterns in planar low temperature dc gas-discharge devices exhibit universal behavior. From the theoretical point of view, dissipative structures of the aforementioned kind are also referred to as attractors. The possible sets of attractors are an important characteristic of the system. The number and/or qualitative nature of attractors may change when changing parameters. The related bifurcation behavior is a central issue of the synergetic approach chosen in the present

  1. Discharge lamp technologies

    Energy Technology Data Exchange (ETDEWEB)

    Dakin, J. [GE Lighting, Cleveland, OH (United States)

    1994-12-31

    This talk is an overview of discharge lamp technology commonly employed in general lighting, with emphasis on issues pertinent to lighting for plant growth. Since the audience is primarily from the plant growth community, and this begins the light source part of the program, we will start with a brief description of the discharge lamps. Challenges of economics and of thermal management make lamp efficiency a prime concern in controlled environment agriculture, so we will emphasize science considerations relating to discharge lamp efficiency. We will then look at the spectra and ratings of some representative lighting products, and conclude with a discussion of technological advance. A general overview of discharge lighting technology can be found in the book of Waymouth (1971). A recent review of low pressure lighting discharge science is found in Dakin (1991). The pioneering paper of Reiling (1964) provides a good introduction to metal halide discharges. Particularly relevant to lighting for plant growth, a recent and thorough treatment of high pressure Na lamps is found in the book by deGroot and vanVliet (1986). Broad practical aspects of lighting application are thoroughly covered in the IES Lighting Handbook edited by Kaufman (1984).

  2. [Cost-effectiveness of needs-oriented discharge planning in high utilizers of mental health care].

    Science.gov (United States)

    Puschner, Bernd; Baumgartner, Ildiko; Loos, Sabine; Völker, Kathleen A; Ramacher, Meike; Sohla, Katja; Grempler, Julia; Becker, Thomas; Kilian, Reinhold

    2012-11-01

    To establish the cost-effectiveness of needs-oriented discharge planning in high utilizers of mental health services. As part of a multicenter RCT (n = 458), costs were measured via the German version of the "Client Sociodemographic and Service Receipt Inventory" (CSSRI-EU), and the EQ-5 D was used to ascertain QALYs. Cost-effectiveness analysis included deriving incremental cost-effectiveness ratios (ICERs) and plotting them onto the cost-effectiveness plane as well as examining cost-effectiveness acceptability taking into account willingness-to-pay. During an 18-month period after discharge from inpatient psychiatric treatment, neither total direct and indirect costs (44,278 € vs. 43,302 €) nor quality-adjusted life years (0.960 vs. 0.958 QALYs) significantly differed by participant allocation to intervention or control groups. Also inspection of ICERs showed that the intervention had no economic advantage over standard care. The intervention is no cost-effective alternative to standard care. Future studies aiming to improve organization of mental care should be considerate of institutional context. © Georg Thieme Verlag KG Stuttgart · New York.

  3. High altitude atmospheric discharges according to the runaway air breakdown mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Symbalisty, E.; Roussel-Dupre, R.; Yukhimuk, V.; Taranenko, Y.

    1997-04-01

    High altitude optical transients - red sprites, blue jets, and elves - are modeled in the context of the relativistic electron runaway air breakdown mechanism. These emissions are usually associated with large mesoscale convective systems (hereafter MCS). In thunderstorms cloud electrification proceeds over a time scale long enough to permit the conducting atmosphere above the cloud to polarize and short out the thunderstorm electric field. When a lightning strike rapidly neutralizes a cloud charge layer runaway driving fields can develop in the stratosphere and mesosphere. According to present simulations of the full runaway process the variety of observed optical emissions are due to the nature of the normal lightning event in the MCS that kick starts the runaway avalanche. In this paper the authors describe some details of the model, present the results of the evolution of the primary electron population, and summarize the initial conditions necessary for different types of discharges. Two companion papers present (a) the predicted optical, gamma ray, and radio emissions caused by these electrical discharges, and (b) the time evolution of the secondary electron population and its implications in terms of observables.

  4. Mechanism of formation of subnanosecond current front in high-voltage pulse open discharge

    Science.gov (United States)

    Schweigert, I. V.; Alexandrov, A. L.; Zakrevsky, Dm. E.; Bokhan, P. A.

    2014-11-01

    The mechanism of subnanosecond current front rise observed previously in the experiment in high-voltage pulse open discharge in helium is studied in kinetic particle-in-cell simulations. The Boltzmann equations for electrons, ions, and fast atoms are solved self-consistently with the Poisson equations for the electrical potential. The partial contributions to the secondary electron emission from the ions, fast atoms, photons, and electrons, bombarding the electrode, are calculated. In simulations, as in the experiment, the discharge glows between two symmetrical cathodes and the anode grid in the midplane at P =6 Torr and the applied voltage of 20 kV. The electron avalanche development is considered for two experimental situations during the last stage of breakdown: (i) with constant voltage and (ii) with decreasing voltage. For case (i), the subnanosecond current front rise is set by photons from the collisional excitation transfer reactions. For the case (ii), the energetic electrons swamp the cathode during voltage drop and provide the secondary electron emission for the subnanosecond current rise, observed in the experiment.

  5. Upgrade Strategy for ALICE at High Rate

    CERN Document Server

    Musa, L

    2012-01-01

    The longterm goal of the ALICE experiment is to provide a precise characterization of the Quark-Gluon Plasma (QGP) state. Such a determination of its properties including initial temperature, degrees of freedom, speed of sound, and in general, transport coefficients would be a major achievement. This would go a long way towards a better understanding of QCD as a genuine multi-particle theory. To achieve this goal, high statistics measurements are required, which will give access also to the very rare physics channels needed to understand the dynamics of this condensed phase of QCD. The general upgrade strategy for the ALICE central barrel is conceived to deal with this challenge with expected Pb-Pb interaction rates of up to 50 kHz, that would provide an accumulated sample of the order of 10 nb^-1 in the period 2019-2023. In this document we sketch the modifications/replacements needed in all ALICE central barrel detectors and online systems (Trigger, DAQ and HLT) for high luminosity running. As the ALICE for...

  6. High Data Rate Architecture (HiDRA)

    Science.gov (United States)

    Hylton, Alan; Raible, Daniel

    2016-01-01

    high-rate laser terminals. These must interface with the existing, aging data infrastructure. The High Data Rate Architecture (HiDRA) project is designed to provide networked store, carry, and forward capability to optimize data flow through both the existing radio frequency (RF) and new laser communications terminal. The networking capability is realized through the Delay Tolerant Networking (DTN) protocol, and is used for scheduling data movement as well as optimizing the performance of existing RF channels. HiDRA is realized as a distributed FPGA memory and interface controller that is itself controlled by a local computer running DTN software. Thus HiDRA is applicable to other arenas seeking to employ next-generation communications technologies, e.g. deep space. In this paper, we describe HiDRA and its far-reaching research implications.

  7. Assessment Model to Identify Patients With Stroke With a High Possibility of Discharge to Home: A Retrospective Cohort Study.

    Science.gov (United States)

    Itaya, Takahiro; Murakami, Yusuke; Ota, Akiko; Nomura, Eiichi; Fukushima, Tomoko; Nishigaki, Masakazu

    2017-10-01

    Discharge planning for inpatients with acute stroke can enhance reasonable use of healthcare resources, as well as improve clinical outcomes and decrease financial burden of patients. Especially, prediction for discharge destination is crucial for discharge planning. This study aimed to develop an assessment model to identify patients with a high possibility of discharge to home after an acute stroke. We reviewed the electronic medical records of 3200 patients with acute stroke who were admitted to a stroke center in Japan between January 1, 2011, and December 31, 2015. The outcome variable was the discharge destination of postacute stroke patients. The predictive variables were identified through logistic regression analysis. Data were divided into 2 data sets: the learning data set (n=2240) for developing the instrument and the test data set (n=960) for evaluating the predictive capability of the model. In all, 1548 (48%) patients were discharged to their homes. Multiple logistic regression analysis identified 5 predictive variables for discharge to home: living situation, type of stroke, functional independence measure motor score on admission, functional independence measure cognitive score on admission, and paresis. The assessment model showed a sensitivity of 85.0% and a specificity of 75.3% with an area under the curve equal to 0.88 (95% confidence interval, 0.86-0.89) when the cutoff point was 10. On evaluating the predictive capabilities, the model showed a sensitivity of 88.0% and a specificity of 68.7% with an area under the curve equal to 0.87 (95% confidence interval, 0.85-0.89). We have developed an assessment model for identifying patients with a high possibility of being discharged to their homes after an acute stroke. This model would be useful for health professionals to adequately plan patients' discharge soon after their admission. © 2017 American Heart Association, Inc.

  8. Photocathodes for High Repetition Rate Light Sources

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Zvi, Ilan [Stony Brook Univ., NY (United States). Dept. of Physics and Astronomy. Center for Accelerator Science and Education

    2014-04-20

    This proposal brought together teams at Brookhaven National Laboratory (BNL), Lawrence Berkeley National Laboratory (LBNL) and Stony Brook University (SBU) to study photocathodes for high repetition rate light sources such as Free Electron Lasers (FEL) and Energy Recovery Linacs (ERL). Below details the Principal Investigators and contact information. Each PI submits separately for a budget through his corresponding institute. The work done under this grant comprises a comprehensive program on critical aspects of the production of the electron beams needed for future user facilities. Our program pioneered in situ and in operando diagnostics for alkali antimonide growth. The focus is on development of photocathodes for high repetition rate Free Electron Lasers (FELs) and Energy Recovery Linacs (ERLs), including testing SRF photoguns, both normal-­conducting and superconducting. Teams from BNL, LBNL and Stony Brook University (SBU) led this research, and coordinated their work over a range of topics. The work leveraged a robust infrastructure of existing facilities and the support was used for carrying out the research at these facilities. The program concentrated in three areas: a) Physics and chemistry of alkali-­antimonide cathodes (BNL – LBNL) b) Development and testing of a diamond amplifier for photocathodes (SBU -­ BNL) c) Tests of both cathodes in superconducting RF photoguns (SBU) and copper RF photoguns (LBNL) Our work made extensive use of synchrotron radiation materials science techniques, such as powder-­ and single-­crystal diffraction, x-­ray fluorescence, EXAFS and variable energy XPS. BNL and LBNL have many complementary facilities at the two light sources associated with these laboratories (NSLS and ALS, respectively); use of these will be a major thrust of our program and bring our understanding of these complex materials to a new level. In addition, CHESS at Cornell will be used to continue seamlessly throughout the NSLS dark period and

  9. Transport studies of high-Z elements in neon edge radiation cooled discharges in TEXTOR-94

    NARCIS (Netherlands)

    Rapp, J.; Tokar, M. Z.; Konen, L.; Koslowski, H. R.; Bertschinger, G.; Brix, M.; Claassen, H.; R. Jaspers,; KramerFlecken, A.; Ohya, K.; Philipps, V.; Pospieszczyk, A.; Samm, U.; Tanabe, T.; Telesca, G.; Unterberg, B.; Van Oost, G.

    1997-01-01

    High-Z materials as tungsten are intended to be used in future fusion reactors due to their low sputtering rates and high melting points. In this context the important question is whether the use of high-Z materials is compatible with the concept of a cold radiative boundary. To investigate the

  10. Dissociation of carbon dioxide using a microhollow cathode discharge plasma reactor: effects of applied voltage, flow rate and concentration

    Science.gov (United States)

    Taylan, O.; Berberoglu, H.

    2015-02-01

    This paper reports an experimental study on dissociating carbon dioxide (CO2) using a microhollow cathode discharge (MHCD) plasma reactor operated at 1 atm. The MHCD plasma reactors can be a promising technology for dissociating gases, including CO2, as they do not require catalysts, they operate at around room temperature, and can be inexpensively built and operated. In this study, CO2 balanced with the carrier gas argon (Ar) was fed through the MHCD reactor, and parametric experiments were conducted to investigate the effects of applied voltage, flow rate, and CO2 mole fraction in the influent on the composition of the products, energy conversion efficiency, and yield. Within the investigated parameter ranges, the maximum energy conversion efficiency of 14% was achieved when the specific energy input was 1.1 eV mol-1, whereas the maximum CO yield of 10.5% was achieved when the specific energy input was 4 eV mol-1. The results also showed that diluting CO2 with Ar increased the yield at an expense of a decrease in energy conversion efficiency. The results of this study provide insights for operating MHCD reactors for efficient gas dissociation at atmospheric pressure.

  11. [HIGH-RISK CHRONICALLY ILL PATIENTS: DIAGNOSTICS, RESULTS AND NURSING INTERVENTIONS UPON DISCHARGE].

    Science.gov (United States)

    Martinez López, Constancio; Martinez de Pinillos, Rafael López; Pereira Torres, Ana Isabel; San Pedro, Ana Isabel Castro; Heras Agudo, Dolores; Robledo González, Ascensión; Olmo Alonso, Carmen; Trujillo Orcha, Natalia

    2015-10-01

    It is after the implementation of the new nursing evaluation/ planning care registers (PCE) in the medical record and the updating of the document/circuit of the All-clear Ensuing Care Report (ICCA) with NANDA, NOC, NIC (NNN) in the first months of the year 2013, that we are contemplating the fulfillment of a descriptive/cross-section study so as to know diagnostics, results and nursing interventions upon discharge of high-risk chronically ill patients and qualitatively in medical hospitalization units and in palliative care. The results obtained at a quantitative level, with an implementation degree of 83 and 94 per cent, respectively, are extremely encouraging. Regarding the quality of care planning, we have identified for the first time in our hospital both the NANDA, the NOC and NIC with the prevalence degree in the units studied.

  12. Electronic Dimmable Ballasts for High-Intensity Discharge Sodium Vapor and Metal Halide Lamps

    Science.gov (United States)

    Boulanger, Richard

    2002-01-01

    Two types of high-intensity discharge lamps were tested using dimmable ballasts. The main purpose for evaluating this lighting system was to determine its efficacy for saving power. Whereas previous variable level lighting systems for HID lamps in Advanced Life Support applications were adjustable in two or three steps using capacitive switching, this system allows for continuously adjustable lamp output. This type of lighting system when used as part of an Advanced Life Support biomass production system would provide only the amount of light energy a crop needed at any particular point in its growth cycle. Since most of the equivalent system mass in an ALS system is from the light energy required to grow the crops, controlling that light energy dynamically over a continuous range of operation would dramatically reduce the power consumption and reduce system mass.

  13. A high voltage pulsed power supply for capillary discharge waveguide applications

    Science.gov (United States)

    Abuazoum, S.; Wiggins, S. M.; Issac, R. C.; Welsh, G. H.; Vieux, G.; Ganciu, M.; Jaroszynski, D. A.

    2011-06-01

    We present an all solid-state, high voltage pulsed power supply for inducing stable plasma formation (density ˜1018 cm-3) in gas-filled capillary discharge waveguides. The pulser (pulse duration of 1 μs) is based on transistor switching and wound transmission line transformer technology. For a capillary of length 40 mm and diameter 265 μm and gas backing pressure of 100 mbar, a fast voltage pulse risetime of 95 ns initiates breakdown at 13 kV along the capillary. A peak current of ˜280 A indicates near complete ionization, and the r.m.s. temporal jitter in the current pulse is only 4 ns. Temporally stable plasma formation is crucial for deploying capillary waveguides as plasma channels in laser-plasma interaction experiments, such as the laser wakefield accelerator.

  14. A readout unit for high rate applications

    CERN Document Server

    Toledo, J; Domínguez, D; Guirao-Elias, A; Müller, H

    2002-01-01

    The LHCb readout unit (RU) is a custom entry stage to the readout network of a data-acquisition or trigger system. It performs subevent building from multiple link inputs toward a readout network via a PCI network interface or alternatively toward a high-speed link, via an S-link interface. Incoming event fragments are derandomized, buffered and assembled into single subevents. This process is based on a low- overhead framing convention and matching of equal event numbers. Programmable logic is used both in the input and output stages of the RU module, which may be configured either as a data-link multiplexer or as entry stage to a readout or trigger network. All FPGAs are interconnected via the PCI bus, which is hosted by a networked microprocessor card. Its main tasks are remote FPGA configuration and initialization of the PCI cards. The RU hardware architecture has been optimized for a throughput of up to 200 MB/s at a 1 MHz trigger rate, as required by the most demanding application, the LHCb level-1 trig...

  15. Estimation and monitoring heat discharge rates using Landsat ETM+ thermal infrared data: a case study in Unzen geothermal field, Kyushu, Japan

    Science.gov (United States)

    Mia, Md. B.; Fujimitsu, Yasuhiro; Bromely, Chris J.

    2012-10-01

    The Unzen geothermal field, our study area is active fumaroles, situated in Shimabara Peninsula of Kyushu Island in Japan. Our prime objectives were (1) to estimate radiative heat flux (RHF), (2) to calculate approximately heat discharge rate (HDR) using the relationship of radiative heat flux with the total heat loss derived from two geothermal field studies and (3) finally, to monitor RHF as well as HDR in our study area using seven sets of Landsat 7 ETM+ images from 2000 to 2009. We used the NDVI (Normalized differential vegetation index) method for spectral emissivity estimation, the mono-window algorithm for land surface temperature (LST) and the Stefan-Boltzmann equation analyzing those satellite TIR images for RHF. We obtained a desired strong correlation of LST above ambient with RHF using random samples. We estimated that the maximum RHF was about 251 W/m2 in 2005 and minimum was about 27 W/m2 in 2001. The highest total RHF was about 39.1 MW in 2005 and lowest was about 12 MW in 2001 in our study region. We discovered that the estimated RHF was about 15.7 % of HDR from our studies. We applied this percentage to estimate heat discharge rate in Unzen geothermal area. The monitoring results showed a single fold trend of HDR from 2000 to 2009 with highest about 252 MW in 2005 and lowest about 78 MW in 2001. In conclusion, TIR remote sensing is thought as the best option for monitoring heat losses from fumaroles with high efficiency and low cost.

  16. Stability of DIII-D high-performance, negative central shear discharges

    Science.gov (United States)

    Hanson, J. M.; Berkery, J. W.; Bialek, J.; Clement, M.; Ferron, J. R.; Garofalo, A. M.; Holcomb, C. T.; La Haye, R. J.; Lanctot, M. J.; Luce, T. C.; Navratil, G. A.; Olofsson, K. E. J.; Strait, E. J.; Turco, F.; Turnbull, A. D.

    2017-05-01

    Tokamak plasma experiments on the DIII-D device (Luxon et al 2005 Fusion Sci. Tech. 48 807) demonstrate high-performance, negative central shear (NCS) equilibria with enhanced stability when the minimum safety factor {{q}\\text{min}} exceeds 2, qualitatively confirming theoretical predictions of favorable stability in the NCS regime. The discharges exhibit good confinement with an L-mode enhancement factor H 89  =  2.5, and are ultimately limited by the ideal-wall external kink stability boundary as predicted by ideal MHD theory, as long as tearing mode (TM) locking events, resistive wall modes (RWMs), and internal kink modes are properly avoided or controlled. Although the discharges exhibit rotating TMs, locking events are avoided as long as a threshold minimum safety factor value {{q}\\text{min}}>2 is maintained. Fast timescale magnetic feedback control ameliorates RWM activity, expanding the stable operating space and allowing access to {β\\text{N}} values approaching the ideal-wall limit. Quickly growing and rotating instabilities consistent with internal kink mode dynamics are encountered when the ideal-wall limit is reached. The RWM events largely occur between the no- and ideal-wall pressure limits predicted by ideal MHD. However, evaluating kinetic contributions to the RWM dispersion relation results in a prediction of passive stability in this regime due to high plasma rotation. In addition, the ideal MHD stability analysis predicts that the ideal-wall limit can be further increased to {β\\text{N}}>4 by broadening the current profile. This path toward improved stability has the potential advantage of being compatible with the bootstrap-dominated equilibria envisioned for advanced tokamak (AT) fusion reactors.

  17. Heat dissipation of high rate Li-SOCl sub 2 primary cells

    Science.gov (United States)

    Cho, Y. I.; Halpert, G.; Deligiannis, E.

    1986-01-01

    The heat dissipation problem occurring in the lithium thionyl chloride cells discharged at relatively high rates under normal discharge conditions is examined. Four heat flow paths were identified, and the thermal resistances of the relating cell components along each flow path were accordingly calculated. From the thermal resistance network analysis, it was demonstrated that about 90 percent of the total heat produced within the cell should be dissipated along the radial direction in a spirally wound cell. In addition, the threshold value of the heat generation rate at which cell internal temperature could be maintained below 100 C, was calculated from total thermal resistance and found to be 2.9 W. However, these calculations were made only at the cell components' level, and the transient nature of the heat accumulation and dissipation was not considered. A simple transient model based on the lumped-heat-capacity concept was developed to predict the time-dependent cell temperature at different discharge rates. The overall objective was to examine the influence of cell design variable from the heat removal point of view under normal discharge conditions and to make recommendations to build more efficient lithium cells.

  18. Post-discharge compliance to venous thromboembolism prophylaxis in high-risk orthopaedic surgery: results from the ETHOS registry.

    Science.gov (United States)

    Bergqvist, David; Arcelus, Juan I; Felicissimo, Paulo

    2012-02-01

    Venous thromboembolism (VTE) risk persists for several weeks following high-risk orthopaedic surgery (HROS). The ETHOS registry evaluated post-operative VTE prophylaxis prescribed, and actual VTE prophylaxis received, compared with the 2004 American College of Chest Physicians (ACCP) guidelines in HROS patients. We performed a subanalysis of ETHOS to assess patient compliance with ACCP-adherent prophylaxis after discharge and the factors predicting poor compliance. Consecutive patients undergoing hip fracture surgery, total hip arthroplasty, or knee arthroplasty were enrolled at discharge from 161 centres in 17 European countries if they had received adequate in-hospital VTE prophylaxis. Data on prescribed and actual prophylaxis received were obtained from hospital charts and patient post-discharge diaries. Good compliance was defined as percentage treatment intake ≥80% with no more than two consecutive days without treatment. A total of 3,484 patients (79.4%) received ACCP-adherent anticoagulant prescription at discharge and 2,999 (86.0%) had an evaluable patient diary. In total, 87.7% of evaluable patients were compliant with prescribed treatment after discharge. The most common reason for non-compliance (33.4%) was "drug was not bought". Injection of treatment was not a barrier to good compliance. Main factors affecting compliance related to purchase of and access to treatment, patient education, the person responsible for administering injections, country, and type of hospital ward at discharge. Within our study population, patient compliance with ACCP-adherent thromboprophylaxis prescribed at discharge was good. Improvements in patient education and prescribing practices at discharge may be important in further raising compliance levels in high-risk orthopaedic surgery patients.

  19. High mitogenomic evolutionary rates and time dependency.

    NARCIS (Netherlands)

    Subramanian, S.; Denver, D.R.; Millar, C.D.; Heupink, T.; Aschrafi, A.; Emslie, S.D.; Baroni, C.; Lambert, D.M.

    2009-01-01

    Using entire modern and ancient mitochondrial genomes of Adelie penguins (Pygoscelis adeliae) that are up to 44000 years old, we show that the rates of evolution of the mitochondrial genome are two to six times greater than those estimated from phylogenetic comparisons. Although the rate of

  20. Pancreatitis - discharge

    Science.gov (United States)

    Chronic pancreatitis - discharge; Pancreatitis - chronic - discharge; Pancreatic insufficiency - discharge; Acute pancreatitis - discharge ... You were in the hospital because you have pancreatitis. This is a swelling of the pancreas. You ...

  1. Preliminary study on heat load using calorimetric measurement during long-pulse high-performance discharges on EAST

    Science.gov (United States)

    Liu, Y. K.; Hamada, N.; Hanada, K.; Gao, X.; Liu, H. Q.; Yu, Y. W.; Qian, J. P.; Yang, L.; Xu, T. J.; Jie, Y. X.; Yao, Y.; Wang, S. S.; Xu, J. C.; Yang, Z. D.; Li, G. S.; EAST Team

    2017-04-01

    Experimental Advanced Superconducting Tokamak (EAST) aims to demonstrate steady-state advanced high-performance H-mode plasmas with an ITER-like configuration, plasma control and heating schemes. The plasma-facing components in EAST are actively cooled, providing good conditions for researching long-pulse and high-energy discharges. A long-pulse high-performance plasma discharge (#59892 discharge) of up to 103 s with a core electron temperature of up to 4.5 keV was sustained with an injected energy exceeding 0.22 GJ in the 2015-2016 experimental campaign. A calorimetric measurement utilizing the temperature increment of cooling water is carried out to calculate the heat load on the strike point region of the lower divertor during long-pulse discharges in EAST. For the long-pulse and high-energy discharges, the comparison of the measurement results for the heat load measured by divertor Langmuir probes and the calorimetry diagnostic indicates that most of the heat load is delivered to the divertor panels as plasma, not radiation, and charge exchange neutrals. The ratio of the heat load on the strike point region of the lower divertor to the total injected energy is on average 42.5% per discharge with the lower single null divertor configuration. If the radiated energy loss measured by the fast bolometer diagnostic is taken into consideration, the ratio is found to be 61.6%. The experimental results and the analysis of the physics involved in these discharges are reported and discussed.

  2. The absorption effect of the Lα-line Supplement to the paper 'On the Correlation Between the Hα-line emission rate and the ablation rate of a hydrogen pellet in tokamak discharges' – Nuclear Fusion 24 (1984) 697

    DEFF Research Database (Denmark)

    Chang, C. T.; Thomsen, Kenneth

    1985-01-01

    Several assumptions made in a previous study of the correlation between the Hα-line emission rate and the ablation rate of a hydrogen pellet injected into a tokamak discharge showed that the emission layer of the ablatant as optically thin with respect to all levels of the principal quantum numbe...

  3. Ordinary High Flows and the Stage-Discharge Relationship in the Arid West Region

    Science.gov (United States)

    2011-07-01

    20
 Figure 12. Daily instantaneous peak discharge percent greater than the daily mean discharge at Agua Fria...45
 Figure 35. Agua Fria...Moenkopi Wash, Dry Beaver Creek, Agua Fria River, and New River Semiarid; Potential evaporation exceeds precipitation; Temperature above

  4. Spatial and temporal evolution of ion energies in high power impulse magnetron sputtering plasma discharge

    Science.gov (United States)

    Hecimovic, A.; Ehiasarian, A. P.

    2010-09-01

    High power impulse magnetron sputtering (HIPIMS) is a novel deposition technology successfully implemented on full scale industrial machines. HIPIMS utilizes short pulses of high power delivered to the target in order to generate high amount of metal ions. The life-span of ions between the pulses and their energy distribution could strongly influence the properties and characteristics of the deposited coating. In modern industrial coating machines the sample rotates on a substrate holder and changes its position and distance with regard to the magnetron. Time resolved measurements of the ion energy distribution function (IEDF) at different distances from the magnetron have been performed to investigate the temporal evolution of ions at various distances from target. The measurements were performed using two pressures, 1 and 3 Pa to investigate the influence of working gas pressure on IEDF. Plasma sampling energy-resolved mass spectroscopy was used to measure the IEDF of Ti1+, Ti2+, Ar1+, and Ar2+ ions in HIPIMS plasma discharge with titanium (Ti) target in Ar atmosphere. The measurements were done over a full pulse period and the distance between the magnetron and the orifice of the mass spectrometer was changed from 25 to 215 mm.

  5. Measurement of Plasma density in High Intensity Discharge Lamps by THz Interferometry

    Science.gov (United States)

    Kieckhafer, Alex; Curry, John

    2008-10-01

    A THz interferometer has been constructed with the goal of directly measuring plasma electron densities in High Intensity Discharge (HID) lamp plasmas. The use of THz frequencies has several advantages. Primary of these is the ability to measure high densities. The 0.6 THz system constructed is capable of measuring densities up to 4x10^15 cm-3. Additionally, the short wavelength of 0.6 THz radiation will allow focal spot sizes smaller than a millimeter in diameter, thus enabling high spatial resolution measurements. The system also differs from traditional microwave interferometry in that heterodyning has been eliminated. In inductively driven lamps the plasma recombines twice per AC cycle, when the voltage drops below a critical value. This time-dependent phase shift of the THz beam will allow calculation of density as a function of time. Zero-points can be acquired during the measurement itself due to the twice-per-cycle recombination of the plasma. Detection using electro-optical or nonlinear optical methods can easily achieve the time resolution required for these measurements, while maintaining sufficient signal-to-noise levels for detection without the assistance of lock-in amplification.

  6. Integration Testing of a Modular Discharge Supply for NASA's High Voltage Hall Accelerator Thruster

    Science.gov (United States)

    Pinero, Luis R.; Kamhawi, hani; Drummond, Geoff

    2010-01-01

    NASA s In-Space Propulsion Technology Program is developing a high performance Hall thruster that can fulfill the needs of future Discovery-class missions. The result of this effort is the High Voltage Hall Accelerator thruster that can operate over a power range from 0.3 to 3.5 kW and a specific impulse from 1,000 to 2,800 sec, and process 300 kg of xenon propellant. Simultaneously, a 4.0 kW discharge power supply comprised of two parallel modules was developed. These power modules use an innovative three-phase resonant topology that can efficiently supply full power to the thruster at an output voltage range of 200 to 700 V at an input voltage range of 80 to 160 V. Efficiencies as high as 95.9 percent were measured during an integration test with the NASA103M.XL thruster. The accuracy of the master/slave current sharing circuit and various thruster ignition techniques were evaluated.

  7. Estimates of Climate Change Impact on River Discharge in Japan Based on a Super-High-Resolution Climate Model

    Directory of Open Access Journals (Sweden)

    Yoshinobu Sato

    2012-01-01

    Full Text Available The impact of climate change on river discharge was assessed by hydrological simulations for several major river basins in Japan using the latest version of a super-high-resolution atmospheric general circulation model (AGCM with a horizontal resolution of about 20 km. Projections were made using two different datasets, one representing the present climate (1980 - 1999 and the other representing the end of the 21st century (2080 - 2099 assuming the SRES A1B scenario. River discharge was estimated by a distributed hydrological model calibrated against observed river discharge in advance. The results showed that even if the amount of precipitation does not change much in the future, river discharge will change significantly because of the increase in rainfall, decrease in snowmelt, and increase in evapotranspiration with higher air temperature. The impact of climate change on river discharge will be more significant in the northern part of Japan, especially in the Tohoku and Hokuriku regions. In these regions, the monthly average river discharge at the end of the 21st century was projected to be more than 200% higher in February and approximately 50 - 60% lower in May compared with the present flow. These results imply that the increase in air temperature has important consequences for the hydrological cycle, particularly in regions where the water supply is currently dominated by snowmelt.

  8. A Simulation of the Effects of Varying Repetition Rate and Pulse Width of Nanosecond Discharges on Premixed Lean Methane-Air Combustion

    Directory of Open Access Journals (Sweden)

    Moon Soo Bak

    2012-01-01

    Full Text Available Two-dimensional kinetic simulation has been carried out to investigate the effects of repetition rate and pulse width of nanosecond repetitively pulsed discharges on stabilizing premixed lean methane-air combustion. The repetition rate and pulse width are varied from 10 kHz to 50 kHz and from 9 ns to 2 ns while the total power is kept constant. The lower repetition rates provide larger amounts of radicals such as O, H, and OH. However, the effect on stabilization is found to be the same for all of the tested repetition rates. The shorter pulse width is found to favor the production of species in higher electronic states, but the varying effects on stabilization are also found to be small. Our results indicate that the total deposited power is the critical element that determines the extent of stabilization over this range of discharge properties studied.

  9. Characteristics of Hospice Programs With Problematic Live Discharges.

    Science.gov (United States)

    Teno, Joan M; Bowman, Jason; Plotzke, Michael; Gozalo, Pedro L; Christian, Thomas; Miller, Susan C; Williams, Cindy; Mor, Vincent

    2015-10-01

    Little is known about how hospice live discharges vary by hospice providers' tax status and chain affiliation. To characterize hospices with high rates of problematic patterns of live discharges. Three hospice-level patterns of live discharges were defined as problematic when the facility rate was at the 90th percentile or higher. A hospice with a high rate of patients discharged, hospitalized, and readmitted to hospice was considered to have a problematic live discharge pattern, which we have referred to as burdensome transition. The two other problematic live discharge patterns examined were live discharge in the first seven days of a hospice stay and live discharge after 180 days in hospice. A multivariate logistic model examined variation in the hospice-level rate of each discharge pattern by the hospice's chain affiliation and profit status. This model also adjusted for facility rates of medical diagnoses, nonwhite patients, average age, and the state in which the hospice program is located. In 2010, 3028 hospice programs had 996,208 discharges, with 18.0% being alive. Each proposed problematic pattern of live discharge varied by chain affiliation. For-profit providers without a chain affiliation had a higher rate of burdensome transitions than did for-profit providers in national chains (18.2% vs. 12.1%, P live discharges are higher among for-profit providers, especially those not affiliated with a hospice chain. Copyright © 2015 American Academy of Hospice and Palliative Medicine. All rights reserved.

  10. An Intelligent Sensor for the Ultra-High-Frequency Partial Discharge Online Monitoring of Power Transformers

    Directory of Open Access Journals (Sweden)

    Jian Li

    2016-05-01

    Full Text Available Ultra-high-frequency (UHF partial discharge (PD online monitoring is an effective way to inspect potential faults and insulation defects in power transformers. The construction of UHF PD online monitoring system is a challenge because of the high-frequency and wide-frequency band of the UHF PD signal. This paper presents a novel, intelligent sensor for UHF PD online monitoring based on a new method, namely a level scanning method. The intelligent sensor can directly acquire the statistical characteristic quantities and is characterized by low cost, few data to output and transmit, Ethernet functionality, and small size for easy installation. The prototype of an intelligent sensor was made. Actual UHF PD experiments with three typical artificial defect models of power transformers were carried out in a laboratory, and the waveform recording method and intelligent sensor proposed were simultaneously used for UHF PD measurement for comparison. The results show that the proposed intelligent sensor is qualified for the UHF PD online monitoring of power transformers. Additionally, three methods to improve the performance of intelligent sensors were proposed according to the principle of the level scanning method.

  11. High-intensity-discharger 400-W sodium ballast. Phase II. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Felper, G.

    1981-10-01

    A research and development program directed toward design, test, and evaluation of an energy efficient High Intensity Discharge (HID) Solid-State 400 Watt Ballast lighting system was undertaken. Under Phase I of the project, the existing ballast was modified, performance characteristics were measured, efficiency was compared with a core/coil ballast including energy loss analysis. Six (6) prototype 400 W High Pressure Sodium Ballasts were built, for verification tests by an independent test facility prior to follow-on performance and life tests. This report covers Phase II of the project which was designed to make test data comparisons on results received from the independent test laboratory, determine methods to increase ballast efficiency, determine the importance of power factors, conduct bulb life tests, perform specification review, performance versus cost analysis, investigate the ballast to determine compliance with new FCC requirement, and determine a line transient specification in respect to solid state ballasting. In addition, Phase II required reliability testing, a manufacturing test plan, a marketing study for solid-state ballast, and the manufacture and delivery of fifteen (15) demonstration ballast units to LBL. These requirements are discussed.

  12. Iterative Boltzmann plot method for temperature and pressure determination in a xenon high pressure discharge lamp

    Energy Technology Data Exchange (ETDEWEB)

    Zalach, J.; Franke, St. [INP Greifswald, Felix-Hausdorff-Str. 2, 17489 Greifswald (Germany)

    2013-01-28

    The Boltzmann plot method allows to calculate plasma temperatures and pressures if absolutely calibrated emission coefficients of spectral lines are available. However, xenon arcs are not very well suited to be analyzed this way, as there are only a limited number of lines with atomic data available. These lines have high excitation energies in a small interval between 9.8 and 11.5 eV. Uncertainties in the experimental method and in the atomic data further limit the accuracy of the evaluation procedure. This may result in implausible values of temperature and pressure with inadmissible uncertainty. To omit these shortcomings, an iterative scheme is proposed that is making use of additional information about the xenon fill pressure. This method is proved to be robust against noisy data and significantly reduces the uncertainties. Intentionally distorted synthetic data are used to illustrate the performance of the method, and measurements performed on a laboratory xenon high pressure discharge lamp are analyzed resulting in reasonable temperatures and pressures with significantly reduced uncertainties.

  13. Determination of soluble bromine in an extra-high-pressure mercury discharge lamp by sodium hydroxide decomposition-suppressed ion chromatography.

    Science.gov (United States)

    Mitsumata, Hiroshi; Mori, Toshio; Maeda, Tatsuo; Kita, Yoshiyuki; Kohatsu, Osamu

    2006-02-01

    We have established a simple method for assaying the quantity of soluble bromine in the discharge tubes of an extra-high-pressure mercury discharge lamp. Each discharge tube is destroyed in 5 ml of 10 mM sodium hydroxide, and the recovered sodium hydroxide solution is analyzed by suppressed-ion chromatography using gradient elution. We have clarified that this method can assay less than 1 microg of soluble bromine in a discharge tube.

  14. Study on the influence of the electrode model on discharge characteristics in High-voltage Pulsed Deplugging Technology

    Science.gov (United States)

    Yan, Bingnan; Jing, Zhou; Liang, Zhao

    2017-05-01

    In the oil-field development, blocking caused by impurities leads to a decline in oil production. The high-voltage pulsed deplugging technology can be applied successfully in oil deplugging. One of the key problems in this technology is the influence of the electrode model on discharge characteristics. In this paper, the electrode structure was studied. Firstly, the influence of the electrode gap on electric-field intensity was studied by using ANSYS simulation. Secondly, a high-voltage pulsed discharge experiment system was built and the discharge characteristics were studied under different static pressure when the electrode gap varied. The results show that the larger the electrode gap, the lower the electric strength and the longer the time delay. Short breakdown time delay would make greater energy of impact waves and better blockage relieving effect.

  15. Dynamics of the microstructure of current channels and the generation of high-energy electrons in nanosecond discharges in air

    Energy Technology Data Exchange (ETDEWEB)

    Karelin, V. I.; Trenkin, A. A., E-mail: trenkin@ntc.vniief.ru; Fedoseev, I. G. [Russian Federal Nuclear Center VNIIEF (Russian Federation)

    2015-12-15

    The results of the three-dimensional numerical simulation of the dynamics of the microstructure of high-voltage nanosecond discharges in air at atmospheric pressure are presented. It is established that the fast (at a time of ≈10 ns) broadening and significant decrease in the gas concentration in the microchannels occur as a result of the ohmic heating of microchannels with the diameter of 1–30 μm. It was shown that the broadening of microchannels in a nanosecond diffusive discharge provides an increase in the ratio of the electric field strength to the gas concentration in microchannels to values sufficient for the generation highenergy electron beams and X-ray bremsstrahlung in them. Features of the dynamics of the system of microchannels and its effect on the efficiency of the generation of high-energy electrons in discharges developing in the microstructuring regime of the current channels are considered.

  16. Transition rate diagrams — A new approach to the study of selective excitation processes: The spectrum of manganese in a Grimm-type glow discharge

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, Zdeněk [LECO Instrumente Plzeň spol. s r.o., Plaská 66, 323 25 Plzeň (Czech Republic); Steers, Edward B.M. [London Metropolitan University, 166-220 Holloway Road, London N7 8DB (United Kingdom); Pickering, Juliet C. [Imperial College London, Prince Consort Road, London SW7 2AZ (United Kingdom); Mushtaq, Sohail [London Metropolitan University, 166-220 Holloway Road, London N7 8DB (United Kingdom)

    2014-02-01

    The emission spectra of manganese observed using a Grimm-type glow discharge in pure argon, argon with 0.3% v/v hydrogen and pure neon were studied in order to identify major excitation and ionization processes of manganese in the plasma. A new procedure is proposed, in which each observed emission line is associated with the corresponding transition between different states of the Mn atom or Mn ion, and, by considering all the observed transitions from and into a specific state, a measure of the total rate is determined at which this state is radiatively populated and depopulated. These resulting population/depopulation rates are then plotted as function of level energy. Such plots, called here “transition rate diagrams”, show the role of individual states in the formation of the observed spectrum and can be used to identify possible selective excitation processes. Also, cascade excitation by radiative decay of higher excited states can be conveniently evaluated in this way. A detailed description of the observed Mn I and Mn II spectra is given for Ar, Ar–H{sub 2} and Ne plasmas and relevant excitation/ionization mechanisms are discussed. Matrix effects in analysis of manganese by glow discharge spectroscopy are discussed. A list of important Mn I and Mn II lines excited in the glow discharge plasma is given. - Highlights: • We measured GD-OES spectra of Mn in Ar, Ar(H) and Ne discharges. • We determined transition rate diagrams of Mn I and Mn II in these discharges. • Using those diagrams, we identified major excitation processes involved.

  17. Synthesis of graphene sheets with high electrical conductivity and good thermal stability by hydrogen arc discharge exfoliation.

    Science.gov (United States)

    Wu, Zhong-Shuai; Ren, Wencai; Gao, Libo; Zhao, Jinping; Chen, Zongping; Liu, Bilu; Tang, Daiming; Yu, Bing; Jiang, Chuanbin; Cheng, Hui-Ming

    2009-02-24

    We developed a hydrogen arc discharge exfoliation method for the synthesis of graphene sheets (GSs) with excellent electrical conductivity and good thermal stability from graphite oxide (GO), in combination with solution-phase dispersion and centrifugation techniques. It was found that efficient exfoliation and considerable deoxygenation of GO, and defect elimination and healing of exfoliated graphite can be simultaneously achieved during the hydrogen arc discharge exfoliation process. The GSs obtained by hydrogen arc discharge exfoliation exhibit a high electrical conductivity of approximately 2 x 10(3) S/cm and high thermal stability with oxidization resistance temperature of 601 degrees C, which are much better than those prepared by argon arc discharge exfoliation (approximately 2 x 10(2) S/cm, 525 degrees C) and by conventional thermal exfoliation (approximately 80 S/cm, 507 degrees C) with the same starting GO. These results demonstrate that this hydrogen arc discharge exfoliation method is a good approach for the preparation of GSs with a good quality.

  18. Possible precursors of ball lightning. Observation of closed loops in high voltage discharges

    Energy Technology Data Exchange (ETDEWEB)

    Alexeff, I.; Rader, M. [Univ. of Tennessee, Knoxville, TN (United States)

    1995-05-01

    Several hundred photographs of ultrahigh voltage discharges have been obtained that show closed current loops. These closed current loops may be precursors of ball lightning. One feature of these discharges may explain why observations of ball lightning may be infrequent; that is, there is a distinct threshold in voltage and/or current below which the closed loops do not occur. This threshold current fits other experimental data but is well above the usually observed currents in natural lightning. 10 refs., 3 figs.

  19. Vegetation and Channel Morphology Responses to Ordinary High Water Discharge Events in Arid West Stream Channels

    Science.gov (United States)

    2009-05-01

    events that occur between periods of drought. It is important to understand how vegetation and stream channel morphology respond to various discharge...because there were no discharge events in our study watersheds during our study period that were large enough to affect this part of the channel...AZ 36.94389103 –109.7106684 Southwest– Northeast Compound/ Single Thread Tropical/ Subtropical Steppe Soft Rock Jurassic Navajo sandstone In a

  20. Ionization Capabilities of Hydronium Ions and High Electric Fields Produced by Atmospheric Pressure Corona Discharge.

    Science.gov (United States)

    Sato, Natsuhiko; Sekimoto, Kanako; Takayama, Mitsuo

    2016-01-01

    Atmospheric pressure corona discharge (APCD) was applied to the ionization of volatile organic compounds. The mass spectra of analytes having aromatic, phenolic, anilinic, basic and aliphatic in nature were obtained by using vapor supply and liquid smear supply methods. The vapor supply method mainly gave protonated analytes [A+H]+ caused by proton transfer from hydronium ion H3O+, except for benzene, toluene and n-hexane that have lower proton affinity. The use of the liquid smear supply method resulted in the formation of molecular ion A·+ and/or dehydride analyte [A-H]+, according to the nature of analytes used. The formation of A·+ without fragment ions could be explained by the electron tunneling via high electric fields 108 V/m at the tip of the corona needle. The dehydride analytes [A-H]+ observed in the mass spectra of n-hexane, di- and tributylamines may be explained by the hydride abstraction from the alkyl chains by the hydronium ion. The hydronium ion can play the two-roles for analytes, i.e., the proton donor to form [A+H]+ and the hydride acceptor to form [A-H]+.

  1. Simplified Flood Inundation Mapping Based On Flood Elevation-Discharge Rating Curves Using Satellite Images in Gauged Watersheds

    Directory of Open Access Journals (Sweden)

    Younghun Jung

    2014-05-01

    Full Text Available This study suggests an approach to obtain flood extent boundaries using spatial analysis based on Landsat-5 Thematic Mapper imageries and the digital elevation model. The suggested approach firstly extracts the flood inundation areas using the ISODATA image-processing algorithm from four Landsat 5TM imageries. Then, the ground elevations at the intersections of the extracted flood extent boundaries and the specified river cross sections are read from the digital elevation to estimate the elevation-discharge relationship. Lastly, the flood extent is generated based on the estimated elevation-discharge relationship. The methodology was tested over two river reaches in Indiana, United States. The estimated elevation-discharge relationship showed a good match with the correlation coefficients varying between 0.82 and 0.99. In addition, self-validation was also performed for the estimated spatial extent of the flood by comparing it to the waterbody extracted from the Landsat images used to develop the elevation-discharge relationship. The result indicated that the match between the estimated and the extracted flood extents was better with higher flood magnitude. We expect that the suggested methodology will help under-developed and developing countries to obtain flood maps, which have difficulties getting flood maps through traditional approaches based on computer modeling.

  2. Antena Kupu - Kupu sebagai Sensor Ultra High Frequency (UHF) untuk Mendeteksi Partial Discharge pada Gas Insulation Substation

    OpenAIRE

    Andre, Hanalde; Khayam, Umar

    2013-01-01

    Penggunaan antena sebagai penerima gelombang elektromagnetik dapat digunakan sebagai alat untuk mendeteksi kegiatan partial discharge (PD) yang terjadi pada paralatan tegangan tinggi. Khususnya pada gas insulation substation (GIS), karakteristik gelombang elektromagnetik yang dihasilkan terletak pada rentang ultra high frequency (UHF) dalam rentang 300 MHz – 3 GHz. Karakteristik antena ultra wide band (UWB) diperlukan untuk mendeteksi PD pada rentang yang lebar. Perancangan antena dilakukan...

  3. Long-lived Ar-Hg plasma in the afterglow of a high-current pulsed discharge

    Energy Technology Data Exchange (ETDEWEB)

    Sergeichev, K. F.; Lukina, N. A.; Fesenko, A. A. [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation)

    2013-02-15

    High-density (n > 10{sup 12} cm{sup -3}) argon-mercury plasma produced by a short (t {approx} 20 {mu}s) high-power pulsed discharge in argon with an admixture of mercury vapor at a discharge current of {approx}50 A, an argon pressure of {approx}4 mm Hg, and a mercury vapor pressure of {approx}10{sup -3} mm Hg was studied using optical spectroscopy and radio physics methods. It is found that the lifetime of this plasma after the end of the discharge pulse is up to 10{sup -2} s. It is shown that such an abnormally long lifetime of such an afterglow plasma, as compared to the plasma of an argon discharge without an admixture of mercury vapor, is related to the long residence time of atoms and ions of both argon and mercury in highly excited states due to chemi-ionization processes involving long-lived metastable argon ions. It is suggested that dissociative recombination of highly excited molecular ions of argon play an important role in the transfer of excitation to argon atoms and ions that are close to autoionization states.

  4. High-power, highly stable KrF laser with a 4-kHz pulse repetition rate

    Energy Technology Data Exchange (ETDEWEB)

    Borisov, V M; El' tsov, A V; Khristoforov, O B [State Research Center of Russian Federation ' Troitsk Institute for Innovation and Fusion Research' , Troitsk, Moscow Region (Russian Federation)

    2015-08-31

    An electric-discharge KrF laser (248 nm) with an average output power of 300 W is developed and studied. A number of new design features are related to the use of a laser chamber based on an Al{sub 2}O{sub 3} ceramic tube. A high power and pulse repetition rate are achieved by using a volume discharge with lateral preionisation by the UV radiation of a creeping discharge in the form of a homogeneous plasma sheet on the surface of a plane sapphire plate. Various generators for pumping the laser are studied. The maximum laser efficiency is 3.1%, the maximum laser energy is 160 mJ pulse{sup -1}, and the pulse duration at half maximum is 7.5 ns. In the case of long-term operation at a pulse repetition rate of 4 kHz and an output power of 300 W, high stability of laser output energy (σ ≤ 0.7%) is achieved using an all-solid-state pump system. (lasers)

  5. High-power, highly stable KrF laser with a 4-kHz pulse repetition rate

    Science.gov (United States)

    Borisov, V. M.; El'tsov, A. V.; Khristoforov, O. B.

    2015-08-01

    An electric-discharge KrF laser (248 nm) with an average output power of 300 W is developed and studied. A number of new design features are related to the use of a laser chamber based on an Al2O3 ceramic tube. A high power and pulse repetition rate are achieved by using a volume discharge with lateral preionisation by the UV radiation of a creeping discharge in the form of a homogeneous plasma sheet on the surface of a plane sapphire plate. Various generators for pumping the laser are studied. The maximum laser efficiency is 3.1%, the maximum laser energy is 160 mJ pulse-1, and the pulse duration at half maximum is 7.5 ns. In the case of long-term operation at a pulse repetition rate of 4 kHz and an output power of 300 W, high stability of laser output energy (σ <= 0.7%) is achieved using an all-solid-state pump system.

  6. High frame rate synthetic aperture duplex imaging

    DEFF Research Database (Denmark)

    Stuart, Matthias Bo; Tomov, Borislav Gueorguiev; Pihl, Michael Johannes

    2013-01-01

    Conventional color flow images are limited in velocity range and can either show the high velocities in systole or be optimized for the lower diastolic velocities. The full dynamics of the flow is, thus, hard to visualize. The dynamic range can be significantly increased by employing synthetic ap...

  7. "Ictal" lateralized periodic discharges.

    Science.gov (United States)

    Sen-Gupta, Indranil; Schuele, Stephan U; Macken, Micheal P; Kwasny, Mary J; Gerard, Elizabeth E

    2014-07-01

    Whether lateralized periodic discharges (LPDs) represent ictal or interictal phenomena, and even the circumstances in which they may represent one or the other, remains highly controversial. Lateralized periodic discharges are, however, widely accepted as being ictal when they are time-locked to clinically apparent symptoms. We sought to investigate the characteristics of "ictal" lateralized periodic discharges (ILPDs) defined by time-locked clinical symptoms in order to explore the utility of using this definition to dichotomize LPDs into "ictal" and "nonictal" categories. Our archive of all continuous EEG (cEEG) reports of adult inpatients undergoing prolonged EEG monitoring for nonelective indications between 2007 and 2011 was searched to identify all reports describing LPDs. Lateralized periodic discharges were considered ILPDs when they were reported as being consistently time-locked to clinical symptoms; LPDs lacking a clear time-locked correlate were considered to be "nonictal" lateralized periodic discharges (NILPDs). Patient charts and available neuroimaging studies were also reviewed. Neurophysiologic localization of LPDs, imaging findings, presence of seizures, discharge outcomes, and other demographic factors were compared between patients with ILPDs and those with NILPDs. p-Values were adjusted for false discovery rate (FDR). One thousand four hundred fifty-two patients underwent cEEG monitoring at our institution between 2007 and 2011. Lateralized periodic discharges were reported in 90 patients, 10 of whom met criteria for ILPDs. Nine of the patients with ILPDs demonstrated motor symptoms, and the remaining patient experienced stereotyped sensory symptoms. Ictal lateralized periodic discharges had significantly increased odds for involving central head regions (odds ratio [OR]=11; 95% confidence interval [CI]=2.16-62.6; p=0.018, FDR adjusted), with a trend towards higher proportion of lesions involving the primary sensorimotor cortex (p=0.09, FDR

  8. Overcharge Protection for 4 V Lithium Batteries at High Rates and Low Temperature

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Guoying; Richardson, Thomas J.

    2010-01-04

    Overcharge protection for 4 V Li{sub 1.05}Mn{sub 1.95}O{sub 4}/lithium cells at charging rates in excess of 1 mA/cm{sup 2} (3C) and at temperatures as low as -20 C was achieved using a bilayer separator coated with two electroactive polymers. High rate and low temperature overcharge protection and discharge performance were improved by employing a design in which the polymer-coated portion of the separator is in parallel with the cell rather than between the electrodes. The effects of different membrane supports for the electroactive polymers are also examined.

  9. Numerical Investigation of Symmetry Breaking and Critical Behavior of the Acoustic Streaming Field in High-Intensity Discharge Lamps

    CERN Document Server

    Baumann, Bernd; Wolff, Marcus; Manders, Freddy; Suijker, Jos

    2014-01-01

    For energy efficiency and material cost reduction it is preferred to drive high-intensity discharge lamps at frequencies of approximately 300 kHz. However, operating lamps at these high frequencies bears the risk of stimulating acoustic resonances inside the arc tube, which can result in low frequency light flicker and even lamp destruction. The acoustic streaming effect has been identified as the link between high frequency resonances and low frequency flicker. A highly coupled 3D multiphysics model has been set up to calculate the acoustic streaming velocity field inside the arc tube of high-intensity discharge lamps. It has been found that the velocity field suffers a phase transition to an asymmetrical state at a critical acoustic streaming force. The system behaves similar to a ferromagnet near the Curie point. Furthermore, it is discussed how the model allows to investigate the light flicker phenomenon. Concerning computer resources the procedure is considerably less demanding than a direct approach wit...

  10. High readmission rate after heart valve surgery

    DEFF Research Database (Denmark)

    Sibilitz, K L; Berg, S K; Thygesen, Lau Caspar

    2015-01-01

    age (hazard ratio (95% CI): 1.3 (1.0-1.6)), male sex (1.2 (1.0-1.5)), mitral valve surgery (1.3 (1.0-1.6)), and infective endocarditis after surgery (1.8 (1.1-3.0), p: 0.01) predicted readmission, whereas higher age (2.3 (1.0-5.4)), higher comorbidity score (3.2 (1.8-6.0)), and infective endocarditis......BACKGROUND: After heart valve surgery, knowledge on long-term self-reported health status and readmission is lacking. Thus, the optimal strategy for out-patient management after surgery remains unclear. METHODS: Using a nationwide survey with linkage to Danish registers with one year follow-up, we...... included all adults 6-12 months after heart valve surgery irrespective of valve procedure, during Jan-June 2011 (n = 867). Participants completed a questionnaire regarding health-status (n = 742), and answers were compared with age- and sex-matched healthy controls. Readmission rates and mortality were...

  11. The Relationship Between Hospital Construction and High-Risk Infant Auditory Function at NICU Discharge: A Retrospective Descriptive Cohort Study.

    Science.gov (United States)

    Willis, Valerie

    2017-01-01

    To describe the difference in auditory function at neonatal intensive care unit (NICU) discharge between high-risk infant cases exposed to hospital construction during NICU stay and those not exposed. Noise produced by routine NICU caregiving exceeds recommended intensity. As California hospitals undergo construction to meet seismic safety regulations, vulnerable neonates are potentially exposed to even higher levels of noise. Ramifications are unknown. Retrospective data-based descriptive cohort design was used to compare high-risk infant auditory function at NICU discharge between hospital construction exposed and unexposed groups. N = 540 infant cases (243 construction exposed and 297 unexposed controls). Infant cases born and discharged from the study site NICU in the year 2010 (unexposed) and year 2015 (exposed) and received a newborn hearing screening by automated auditory brainstem evoked response (ABER) prior to discharge with results reported. Infant cases excluded: hearing screen results by ABER unavailable, potentially confounding characteristics (congenital infection, major anomalies including cleft lip and/or palate), and transferred into or out of the study site. ABER. descriptive statistics (SPSS Version 24.0), hypothesis testing, correlation, and logistic regression. The difference in auditory function at NICU discharge between high-risk infant cases exposed to hospital construction noise and those unexposed was statistically insignificant, χ2 = 1.666, df = 4, p = .1968, 95% confidence interval [-0.635, 2.570]. More research is needed to better understand whether hospital construction exposure during NICU admission negatively affects high-risk infant auditory function. Findings may catalyze theory development, future research, and child health policy.

  12. Effectiveness of structured planned post discharge support to patients with chronic obstructive pulmonary disease for reducing readmission rates

    DEFF Research Database (Denmark)

    Pedersen, Preben Ulrich; Ersgard, Karen Bagger; Soerensen, Tina Brandt

    2017-01-01

    BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a preventable and treatable disease, characterized by airflow limitation. The disease has a significant impact on the lives of patients and is a challenge for the health care due to readmissions to hospitals. OBJECTIVES: This review aimed...... to identify, appraise and synthesize the best available evidence on the effectiveness of discharge interventions that can reduce readmission of patients with COPD. TYPES OF PARTICIPANTS: Hospitalized patients, aged 18 years or over, who had been diagnosed with COPD and were admitted to hospital due to acute...... exacerbation. TYPES OF INTERVENTIONS: Studies that evaluated discharge interventions that supported patients managing symptoms of COPD. TYPES OF STUDIES: Randomized controlled trials, non-randomized controlled trials, quasi-experimental or cohort studies. OUTCOMES: Readmission, defined as hospitalization...

  13. Evaluation of the contact switch materials in high voltage power supply for generate of underwater shockwave by electrical discharge

    Directory of Open Access Journals (Sweden)

    K Higa

    2016-10-01

    Full Text Available We have developed the high voltage power-supply unit by Cockcroft-Walton circuit for ingenerate high pressure due to underwater shockwave by electrical discharge. This high voltage power supply has the problem of the metal contact switch operation that contact switch stop by melting and bonding due to electrical spark. We have studied the evaluation of materials of contact switch for the reducing electrical energy loss and the problem of contact switch operation. In this research, measurement of discharge voltage and high pressure due to underwater shockwave was carried out using the contact switch made of different materials as brass plate, brass-carbon plate-brass and carbon block. The contact switch made of carbon is effective to reduce energy loss and problem of contactor switch operation.

  14. High salinity tolerance of the Red Sea coral Fungia granulosa under desalination concentrate discharge conditions: an in situ photophysiology experiment

    KAUST Repository

    Van Der Merwe, Riaan

    2014-11-10

    Seawater reverse osmosis desalination concentrate may have chronic and/or acute impacts on the marine ecosystems in the near-field area of the discharge. Environmental impact of the desalination plant discharge is supposedly site- and volumetric- specific, and also depends on the salinity tolerance of the organisms inhabiting the water column in and around a discharge environment. Scientific studies that aim to understand possible impacts of elevated salinity levels are important to assess detrimental effects to organisms, especially for species with no mechanism of osmoregulation, e.g., presumably corals. Previous studies on corals indicate sensitivity toward hypo- and hyper-saline environments with small changes in salinity already affecting coral physiology. In order to evaluate sensitivity of Red Sea corals to increased salinity levels, we conducted a long-term (29 days) in situ salinity tolerance transect study at an offshore seawater reverse osmosis (SWRO) discharge on the coral Fungia granulosa. While we measured a pronounced increase in salinity and temperature at the direct outlet of the discharge structure, effects were indistinguishable from the surrounding environment at a distance of 5 m. Interestingly, corals were not affected by varying salinity levels as indicated by measurements of the photosynthetic efficiency. Similarly, cultured coral symbionts of the genus Symbiodinium displayed remarkable tolerance levels in regard to hypo- and hypersaline treatments. Our data suggest that increased salinity and temperature levels from discharge outlets wear off quickly in the surrounding environment. Furthermore, F. granulosa seem to tolerate levels of salinity that are distinctively higher than reported for other corals previously. It remains to be determined whether Red Sea corals in general display increased salinity tolerance, and whether this is related to prevailing levels of high(er) salinity in the Red Sea in comparison to other oceans.

  15. High speed imaging, lightning mapping arrays and thermal imaging: a synergy for the monitoring of electrical discharges at the onset of volcanic explosions

    Science.gov (United States)

    Gaudin, Damien; Cimarelli, Corrado; Behnke, Sonja; Cigala, Valeria; Edens, Harald; McNutt, Stefen; Smith, Cassandra; Thomas, Ronald; Van Eaton, Alexa

    2017-04-01

    Volcanic lightning is being increasingly studied, due to its great potential for the detection and monitoring of ash plumes. Indeed, it is observed in a large number of ash-rich volcanic eruptions and it produces electromagnetic waves that can be detected remotely in all weather conditions. Electrical discharges in volcanic plume can also significantly change the structural, chemical and reactivity properties of the erupted material. Although electrical discharges are detected in various regions of the plume, those happening at the onset of an explosion are of particular relevance for the early warning and the study of volcanic jet dynamics. In order to better constrain the electrical activity of young volcanic plumes, we deployed at Sakurajima (Japan) in 2015 a multiparametric set-up including: i) a lightning mapping array (LMA) of 10 VHF antennas recording the electromagnetic waves produced by lightning at a sample rate of 25 Msps; ii) a visible-light high speed camera (5000 frames per second, 0.5 m pixel size, 300 m field of view) shooting short movies (approx. duration 1 s) at different stages of the plume evolution, showing the location of discharges in relation to the plume; and iii) a thermal camera (25 fps, 1.5 m pixel size, 800 m field of view) continuously recording the plume and allowing the estimation of its main source parameters (volume, rise velocity, mass eruption rate). The complementarity of these three setups is demonstrated by comparing and aggregating the data at various stages of the plume development. In the earliest stages, the high speed camera spots discrete small discharges, that appear on the LMA data as peaks superimposed to the continuous radio frequency (CRF) signal. At later stages, flashes happen less frequently and increase in length. The correspondence between high speed camera and LMA data allows to define a direct correlation between the length of the flash and the intensity of the electromagnetic signal. Such correlation is

  16. High data rate optical transceiver terminal

    Science.gov (United States)

    Clarke, E. S.

    1973-01-01

    The objectives of this study were: (1) to design a 400 Mbps optical transceiver terminal to operate from a high-altitude balloon-borne platform in order to permit the quantitative evaluation of a space-qualifiable optical communications system design, (2) to design an atmospheric propagation experiment to operate in conjunction with the terminal to measure the degrading effects of the atmosphere on the links, and (3) to design typical optical communications experiments for space-borne laboratories in the 1980-1990 time frame. As a result of the study, a transceiver package has been configured for demonstration flights during late 1974. The transceiver contains a 400 Mbps transmitter, a 400 Mbps receiver, and acquisition and tracking receivers. The transmitter is a Nd:YAG, 200 Mhz, mode-locked, CW, diode-pumped laser operating at 1.06 um requiring 50 mW for 6 db margin. It will be designed to implement Pulse Quaternary Modulation (PQM). The 400 Mbps receiver utilizes a Dynamic Crossed-Field Photomultiplier (DCFP) detector. The acquisition receiver is a Quadrant Photomultiplier Tube (QPMT) and receives a 400 Mbps signal chopped at 0.1 Mhz.

  17. The Effect of the Mode of Gas Preionization on the Parameters of Runaway Electrons in High-Pressure Discharges

    Science.gov (United States)

    Kozhevnikov, V. Yu.; Kozyrev, A. V.; Semeniuk, N. S.

    2017-04-01

    The results of theoretical modeling of the process of formation of a nanosecond discharge in a coaxial discharge gap filled with a high-pressure gas are presented. Two cardinally different evolution scenarios of the nanosecond discharge are addressed: A) in a uniformly volume pre-ionized gas medium and B) in a strongly spatially-nonuniform initially-ionized region near the cathode with a small curvature radius. Relying on the minimal mathematical model of a high-voltage discharge and the description of the physical kinetics of runaway electrons, it is shown using the Boltzmann kinetic equation that the amplitude and duration of a current pulse of runaway electrons and their energy spectrum strongly depend on the mode of gas preionization in the gap. In particular, the other conditions being equal, near-cathode initiation gives rise to the generation of a large group of low-energy runaway electrons within the late current-switching stage. The volume-homogeneous gas preionization can reduce the number of fast electrons by nearly two orders of magnitude compared to the regime without preionization.

  18. Time-dependent simulation of plasma and electrodes in high-intensity discharge lamps with different electrode shapes

    CERN Document Server

    Flesch, P

    2003-01-01

    The subject of this paper is the modelling of d.c. and a.c. high-intensity Hg-discharge lamps with differently shaped electrodes. Different arc attachments on the electrodes are studied and insight for the development of new electrodes is gained. The model includes the entire discharge plasma (plasma column, hot plasma spots in front of electrodes, near-electrode non-LTE-plasma) as well as anode and cathode. No subdivision of the discharge space into different regions is necessary (like space charge layer, ionization zone, plasma column). This is achieved by using a differential equation for a non-LTE electrical conductivity which is applicable for local thermal equilibrium (LTE-)regions as well as for non-LTE plasma regions close to the electrodes in a high pressure plasma. Modelling results for a 0.6 MPa mercury discharge considering six different electrode shapes (anode and cathode) are presented and compared with experimental results. The electrodes have different diameters and different electrode tips, s...

  19. Research in karst aquifers developed in high-mountain areas combining KARSYS models with springs discharge records. Picos de Europa, Spain

    Science.gov (United States)

    Ballesteros, Daniel; Meléndez, Mónica; Malard, Arnauld; Jiménez-Sánchez, Montserrat; Heredia, Nemesio; Jeannin, Pierre-Yves; García-Sansegundo, Joaquín

    2014-05-01

    The study of karst aquifers developed in high-mountain areas is quite complex since the application of many techniques of hydrogeology in these areas is difficult, expensive, and requires many hours of field work. In addition, the access to the study area is usually conditioned by the orography and the meteorological conditions. A pragmatic approach to study these aquifers can be the combination of geometric models of the aquifer with the monitoring of the discharge rate of springs and the meteorological records. KARSYS approach (Jeannin et al. 2013) allows us to elaborate a geometric model of karst aquifers establishing the boundaries of the groundwater bodies, the main drainage axes and providing evidences of the catchment delineation of the springs. The aim of this work is to analyse the functioning of the karst aquifer from the western and central part of the Picos de Europa Mountains (Spain) combining the KARSYS approach, the discharge record from two springs and the meteorological records (rain, snow and temperature). The Picos de Europa (North Spain) is a high-mountains area up to 2.6 km altitude with 2,500 mm/year of precipitations. The highest part of these mountains is covered by snow four to seven months a year. The karst aquifer is developed in Carboniferous limestone which is strongly compartmentalized in, at least, 17 groundwater bodies. The method of work includes: 1) the elaboration of a hydrogeological 3D model of the geometry of the karst aquifers by KARSYS approach, 2) the definition of the springs catchment areas based on the hydrogeological 3D model, 3) the selection of two representative springs emerging from the aquifers to study it, 4) the continuous monitoring of water levels in two karst springs since October 2013, 5) the transformation of the water level values to flow values using height-stream relation curves constructed by measures of the spring discharge, and 5) the comparison of the spring discharge rate records and meteorological

  20. The Effect of Minimum Wage Rates on High School Completion

    Science.gov (United States)

    Warren, John Robert; Hamrock, Caitlin

    2010-01-01

    Does increasing the minimum wage reduce the high school completion rate? Previous research has suffered from (1. narrow time horizons, (2. potentially inadequate measures of states' high school completion rates, and (3. potentially inadequate measures of minimum wage rates. Overcoming each of these limitations, we analyze the impact of changes in…

  1. Initiation of ignition by the action of a high-current pulsed discharge on a gas

    NARCIS (Netherlands)

    Starikovskii, AY

    2003-01-01

    The possibility of nonthermal initiation of chemical reactions by a uniform pulsed nanosecond discharge is demonstrated. Dependences of variation of the ignition delay on initial conditions are obtained. It is shown that the main role in combustion initiation under conditions of a pulsed gas

  2. High-pressure behaviour of an X-ray preionized discharge pumped XeCl laser

    NARCIS (Netherlands)

    Gerritsen, J.W.; Ernst, G.J.

    1988-01-01

    The output characteristics are described of an X-ray preionized discharge pumped XeCl laser, fed by a low-impedance pulse forming line (PFL), at pressures up to 12 bar. The influence of a multichannel rail gap placed between the PFL and the laser head on the output energy was studied. We found an

  3. Numerical Modeling of Pulsed Electrical Discharges for High-Speed Flow Control

    Science.gov (United States)

    2012-02-01

    compute the electric potential: r2 = =0 (6) where 0 is the permittivity of free space. B. Gas Properties and Boundary Conditions The 15-species, 42...Density Measurements in Air and Air/ Fuel Nanosecond Pulse Discharges by Laser Induced Fluorescence," Journal of Physics D: Applied Physics, Vol. 42

  4. Impact of pulsed-electric field and high-voltage electrical discharges on red wine microbial stabilization and quality characteristics.

    Science.gov (United States)

    Delsart, C; Grimi, N; Boussetta, N; Miot Sertier, C; Ghidossi, R; Vorobiev, E; Mietton Peuchot, M

    2016-01-01

    In this study, pulsed-electric fields (PEF) and high-voltage electrical discharges (HVED) are proposed as new techniques for the microbial stabilization of red wines before bottling. The efficiency of the treatment was then evaluated. PEF and HVED-treatments have been applied to wine for the inactivation of Oenococcus oeni CRBO 9304, O. oeni CRBO 0608, Pediococcus parvulus CRBO 2.6 and Brettanomyces bruxellensis CB28. Different treatment times (1, 2, 4, 6, 8 and 10 ms) were used at 20 kV cm(-1) for the PEF treatments and at 40 kV for the HVED treatments, which correspond to applied energies from 80 to 800 kJ l(-1) . The effects of the treatments on the microbial inactivation rate and on various characteristics of red wines (phenolic composition, chromatic characteristics and physico-chemical parameters) were measured. The application of PEF or HVED treatments on red wine allowed the inactivation of alteration yeasts (B. bruxellensis CB28) and bacteria (O. oeni CRBO 9304, O. oeni CRBO 0608 and P. parvulus CRBO 2.6). The electric discharges at 40 kV were less effective than the PEF even after 10 ms of treatments. Indeed, 4 ms of PEF treatment at 20 kV cm(-1) were sufficient to inactivate all micro-organisms present in the wines. Also, the use of PEF had no negative impact on the composition of wines compared to the HVED treatments. Contrary to PEF, the phenolics compounds were degraded after the HVED treatment and the physico-chemical composition of wine were modified with HVED. PEF technology seems to be an interesting alternative to stabilize microbiologically wines before bottling and without modifying their composition. This process offers many advantages for winemakers: no chemical inputs, low energy consumption (320 kJ l(-1) ), fast (treatment time of 4 ms) and athermal (ΔT ≈ 10°C). © 2015 The Society for Applied Microbiology.

  5. High regression rate, high density hybrid fuels Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR program will investigate high energy density novel nanofuels combined with high density binders for use with an N2O oxidizer. Terves has developed...

  6. Development and application of network virtual instrument for emission spectrum of pulsed high-voltage direct current discharge

    Science.gov (United States)

    Gong, X.; Wu, Q.

    2017-12-01

    Network virtual instrument (VI) is a new development direction in current automated test. Based on LabVIEW, the software and hardware system of VI used for emission spectrum of pulsed high-voltage direct current (DC) discharge is developed and applied to investigate pulsed high-voltage DC discharge of nitrogen. By doing so, various functions are realized including real time collection of emission spectrum of nitrogen, monitoring operation state of instruments and real time analysis and processing of data. By using shared variables and DataSocket technology in LabVIEW, the network VI system based on field VI is established. The system can acquire the emission spectrum of nitrogen in the test site, monitor operation states of field instruments, realize real time face-to-face interchange of two sites, and analyze data in the far-end from the network terminal. By employing the network VI system, the staff in the two sites acquired the same emission spectrum of nitrogen and conducted the real time communication. By comparing with the previous results, it can be seen that the experimental data obtained by using the system are highly precise. This implies that the system shows reliable network stability and safety and satisfies the requirements for studying the emission spectrum of pulsed high-voltage discharge in high-precision fields or network terminals. The proposed architecture system is described and the target group gets the useful enlightenment in many fields including engineering remote users, specifically in control- and automation-related tasks.

  7. Apparatus and method for tuned unsteady flow purging of high pulse rate spark gaps

    Energy Technology Data Exchange (ETDEWEB)

    Thayer, W.J. III.

    1988-10-12

    A spark gap switch apparatus is disclosed which is capable of operating at a high pulse rate which comprises an insulated housing; a pair of spaced apart electrodes each having one end thereof within a first bore formed in the housing and defining a spark gap therebetween; pressure wave reflector means in the first bore in the housing and spaced from the spark gap and capable of admitting purge flow; and a second enlarged bore contiguous with the first bore and spaced from the opposite side of the spark gap; whereby pressure waves generated during discharge of a spark across the spark gap will reflect off the wave reflector means and back from the enlarged bore to the spark gap to clear from the spark gap hot gases residues generated during the discharge and simultaneously restore the gas density and pressure in the spark gap to its initial value. 8 figs.

  8. Apparatus and method for tunes unsteady flow purging of high pulse rate spark gaps

    Energy Technology Data Exchange (ETDEWEB)

    Thayer, W.J. III.

    1990-11-13

    This patent describes a spark gap switch apparatus capable of operating at a high pulse rate. It comprises: an insulated housing; a pair of spaced apart electrodes each having one end thereof within a first bore formed in the housing and defining a spark gap therebetween; pressure wave reflector means in the first bore in the housing and spaced from the spark gap; and a second enlarged bore contiguous with the first bore and spaced from the opposite side of the spark gap from the wave reflector means; whereby pressure waves generated during discharge of a spark across the spark gap will reflect off the reflector means and back from the enlarged bore to the spark gap to clear from the spark gap hot gas residues generated during the discharge and reestablish the initial pressure and density of purge gas within the spark gap.

  9. Apparatus and method for tuned unsteady flow purging of high pulse rate spark gaps

    Energy Technology Data Exchange (ETDEWEB)

    Thayer, III, William J. (Kent, WA)

    1990-01-01

    A spark gap switch apparatus is disclosed which is capable of operating at a high pulse rate which comprises an insulated housing; a pair of spaced apart electrodes each having one end thereof within a first bore formed in the housing and defining a spark gap therebetween; a pressure wave reflector in the first bore in the housing and spaced from the spark gap and capable of admitting purge flow; and a second enlarged bore contiguous with the first bore and spaced from the opposite side of the spark gap; whereby pressure waves generated during discharge of a spark across the spark gap will reflect off the wave reflector and back from the enlarged bore to the spark gap to clear from the spark gap hot gases residues generated during the discharge and simultaneously restore the gas density and pressure in the spark gap to its initial value.

  10. Balancing current drive and heating in DIII-D high noninductive current fraction discharges through choice of the toroidal field

    Science.gov (United States)

    Ferron, J. R.; Holcomb, C. T.; Luce, T. C.; Politzer, P. A.; Turco, F.; DeBoo, J. C.; Doyle, E. J.; In, Y.; La Haye, R. J.; Murakami, M.; Okabayashi, M.; Park, J. M.; Petrie, T. W.; Petty, C. C.; Reimerdes, H.

    2011-11-01

    In order to maintain stationary values of the stored energy and the plasma current in a tokamak discharge with all of the current driven noninductively, the sum of the α-heating power and the power required to provide externally driven current must be equal to the power required to maintain the pressure against transport losses. In a study of high noninductive current fraction discharges in the DIII-D tokamak, it is shown that in the case of present-day tokamaks with no α-heating, adjustment of the toroidal field strength (BT) is a tool to obtain this balance between the required current drive and heating powers with other easily modifiable discharge parameters (βN, q95, discharge shape, ne) fixed at values chosen to satisfy specific constraints. With all of the external power sources providing both heating and current drive, and βN and q95 fixed, the fraction of externally driven current scales with BT with little change in the bootstrap current fraction, thus allowing the noninductive current fraction to be adjusted.

  11. Efficient Activation of High-Loading Sulfur by Small CNTs Confined Inside a Large CNT for High-Capacity and High-Rate Lithium-Sulfur Batteries.

    Science.gov (United States)

    Jin, Feiying; Xiao, Suo; Lu, Lijie; Wang, Yong

    2016-01-13

    Sulfur with a high specific capacity of 1673 mAh g(-1) is yet to be used as commercial cathode for lithium batteries because of its low utilization rate and poor cycle stability. In this work, a tube-in-tube carbon structure is demonstrated to relieve the critical problems with sulfur cathode: poor electrical conductivity, dissolution of lithium polysulfides, and large volume change during cycling. A number of small carbon nanotubes (∼20 nm in diameter) and a high loading amount of 85.2 wt % sulfur are both filled completely inside a large amorphous carbon nanotube (∼200 nm in diameter). Owing to the presence of these electrically conductive, highly flexible and structurally robust small CNTs and a large CNT overlayer, sulfur material exhibits a high utilization rate and delivers a large discharge capacity of 1633 mAh g(-1) (based on the mass of sulfur) at 0.1 C, approaching its theoretical capacity (1673 mAh g(-1)). The obtained S-CNTs@CNT electrode demonstrates superior high-rate cycling performances. Large discharge capacities of ∼1146, 1121, and 954 mAh g(-1) are observed after 150 cycles at large current rates of 1, 2, and 5 C, respectively.

  12. High-Rate Strong-Signal Quantum Cryptography

    Science.gov (United States)

    Yuen, Horace P.

    1996-01-01

    Several quantum cryptosystems utilizing different kinds of nonclassical lights, which can accommodate high intensity fields and high data rate, are described. However, they are all sensitive to loss and both the high rate and the strong-signal character rapidly disappear. A squeezed light homodyne detection scheme is proposed which, with present-day technology, leads to more than two orders of magnitude data rate improvement over other current experimental systems for moderate loss.

  13. Origin of life: hypothesized roles of high-energy electrical discharges, infrared radiation, thermosynthesis and pre-photosynthesis.

    Science.gov (United States)

    Trevors, J T

    2012-12-01

    The hypothesis is proposed that during the organization of pre-biotic bacterial cell(s), high-energy electrical discharges, infrared radiation (IR), thermosynthesis and possibly pre-photosynthesis were central to the origin of life. High-energy electrical discharges generated some simple organic molecules available for the origin of life. Infrared radiation, both incoming to the Earth and generated on the cooling Earth with day/night and warming/cooling cycles, was a component of heat engine thermosynthesis before enzymes and the genetic code were present. Eventually, a primitive forerunner of photosynthesis and the capability to capture visible light emerged. In addition, the dual particle-wave nature of light is discussed from the perspective that life requires light acting both as a wave and particle.

  14. Laser sustained discharge nozzle apparatus for the production of an intense beam of high kinetic energy atomic species

    Science.gov (United States)

    Cross, Jon B.; Cremers, David A.

    1988-01-01

    Laser sustained discharge apparatus for the production of intense beams of high kinetic energy atomic species. A portion of the plasma resulting from a laser sustained continuous optical discharge which generates energetic atomic species from a gaseous source thereof is expanded through a nozzle into a region of low pressure. The expanded plasma contains a significant concentration of the high kinetic energy atomic species which may be used to investigate the interaction of surfaces therewith. In particular, O-atoms having velocities in excess of 3.5 km/s can be generated for the purpose of studying their interaction with materials in order to develop protective materials for spacecraft which are exposed to such energetic O-atoms during operation in low earth orbit.

  15. High-performance cathode elements for gas-discharge light sources

    Directory of Open Access Journals (Sweden)

    Sevastyanov V. V.

    2009-02-01

    Full Text Available Application of cathode elements of the arc-discharge activator made on the basis of developed material — alloy of iridium and rare-earth metals (of cerium group — has been suggested. The working samples of arc lamps have been produced and tested. The location of metal-alloy cathode has been optimized. The tests demonstrated, that after 4500 hours of work the lighting-up and glowing parameters of such lamps remained stable.

  16. Effect of hole geometry and Electric-Discharge Machining (EDM) on airflow rates through small diameter holes in turbine blade material

    Science.gov (United States)

    Hippensteele, S. A.; Cochran, R. P.

    1980-01-01

    The effects of two design parameters, electrode diameter and hole angle, and two machine parameters, electrode current and current-on time, on air flow rates through small-diameter (0.257 to 0.462 mm) electric-discharge-machined holes were measured. The holes were machined individually in rows of 14 each through 1.6 mm thick IN-100 strips. The data showed linear increase in air flow rate with increases in electrode cross sectional area and current-on time and little change with changes in hole angle and electrode current. The average flow-rate deviation (from the mean flow rate for a given row) decreased linearly with electrode diameter and increased with hole angle. Burn time and finished hole diameter were also measured.

  17. Low productivity of Chinook salmon strongly correlates with high summer stream discharge in two Alaskan rivers in the Yukon drainage

    Science.gov (United States)

    Neuswanger, Jason R.; Wipfli, Mark S.; Evenson, Matthew J.; Hughes, Nicholas F.; Rosenberger, Amanda E.

    2015-01-01

    Yukon River Chinook salmon (Oncorhynchus tshawytscha) populations are declining for unknown reasons, creating hardship for thousands of stakeholders in subsistence and commercial fisheries. An informed response to this crisis requires understanding the major sources of variation in Chinook salmon productivity. However, simple stock–recruitment models leave much of the variation in this system’s productivity unexplained. We tested adding environmental predictors to stock–recruitment models for two Yukon drainage spawning streams in interior Alaska — the Chena and Salcha rivers. Low productivity was strongly associated with high stream discharge during the summer of freshwater residency for young-of-the-year Chinook salmon. This association was more consistent with the hypothesis that sustained high discharge negatively affects foraging conditions than with acute mortality during floods. Productivity may have also been reduced in years when incubating eggs experienced major floods or cold summers and falls. These freshwater effects — especially density dependence and high discharge — helped explain population declines in both rivers. They are plausible as contributors to the decline of Chinook salmon throughout the Yukon River drainage.

  18. Ignition and afterglow dynamics of a high pressure nanosecond pulsed helium micro-discharge: II. Rydberg molecules kinetics

    Science.gov (United States)

    Carbone, Emile A. D.; Schregel, Christian-Georg; Czarnetzki, Uwe

    2016-10-01

    In this paper, we discuss the experimental results presented in Schregel et al (2016 Plasma Sources Sci. Technol. 25 054003) on a high pressure micro-discharge operated in helium and driven by nanosecond voltage pulses. A simple global plasma chemistry model is developed to describe the ions, excited atomic and molecular species dynamics in the ignition and early afterglow regimes. The existing experimental data on high pressure helium kinetics is reviewed and critically discussed. It is highlighted that several inconsistencies in the branching ratio of neutral assisted associative and dissociative processes currently exist in the literature and need further clarification. The model allows to pinpoint the mechanisms responsible for the large amounts of Rydberg molecules produced in the discharge and for the helium triplet metastable state in the afterglow. The main losses of electrons are also identified. The fast quenching of excited He (n  >  3) states appears to be a significant source of Rydberg molecules which has been previously neglected. The plasma model finally draws a simplified, but still accurate description of high pressure helium discharges based on available experimental data for ion and neutral helium species.

  19. Highly efficient resistive plate chambers for high rate environment

    CERN Document Server

    Cwiok, M; Górski, M; Królikowski, J

    1999-01-01

    The full scale prototype of an inverted double gap RPC module for ME-1/1 station of the CMS detector was tested in the gamma irradiation facility at the CERN SPS muon beam. The chamber made of medium resistivity bakelite and filled with "green gas" mixture of C /sub 2/H/sub 2/F/sub 4//iso-butane/SF/sub 6/ has wide efficiency plateau and good timing properties when operated in avalanche mode under continuous irradiation with strong /sup 137/Cs source for rates up to about 5 kHz/cm/sup 2//gap. (10 refs).

  20. High rate flame synthesis of highly crystalline iron oxide nanorods

    Science.gov (United States)

    Merchan-Merchan, W.; Saveliev, A. V.; Taylor, A. M.

    2008-03-01

    Single-step flame synthesis of iron oxide nanorods is performed using iron probes inserted into an opposed-flow methane oxy-flame. The high temperature reacting environment of the flame tends to convert elemental iron into a high density layer of iron oxide nanorods. The diameters of the iron oxide nanorods vary from 10 to 100 nm with a typical length of a few microns. The structural characterization performed shows that nanorods possess a highly ordered crystalline structure with parameters corresponding to cubic magnetite (Fe3O4) with the [100] direction oriented along the nanorod axis. Structural variations of straight nanorods such as bends, and T-branched and Y-branched shapes are frequently observed within the nanomaterials formed, opening pathways for synthesis of multidimensional, interconnected networks.

  1. Characterizing hyporheic exchange processes using high-frequency electrical conductivity-discharge relationships on subhourly to interannual timescales

    Science.gov (United States)

    Singley, Joel G.; Wlostowski, Adam N.; Bergstrom, Anna J.; Sokol, Eric R.; Torrens, Christa L.; Jaros, Chris; Wilson, Colleen E.; Hendrickson, Patrick J.; Gooseff, Michael N.

    2017-05-01

    Concentration-discharge (C-Q) relationships are often used to quantify source water contributions and biogeochemical processes occurring within catchments, especially during discrete hydrological events. Yet, the interpretation of C-Q hysteresis is often confounded by complexity of the critical zone, such as numerous source waters and hydrochemical nonstationarity. Consequently, researchers must often ignore important runoff pathways and geochemical sources/sinks, especially the hyporheic zone because it lacks a distinct hydrochemical signature. Such simplifications limit efforts to identify processes responsible for the transience of C-Q hysteresis over time. To address these limitations, we leverage the hydrologic simplicity and long-term, high-frequency Q and electrical conductivity (EC) data from streams in the McMurdo Dry Valleys, Antarctica. In this two end-member system, EC can serve as a proxy for the concentration of solutes derived from the hyporheic zone. We utilize a novel approach to decompose loops into subhysteretic EC-Q dynamics to identify individual mechanisms governing hysteresis across a wide range of timescales. We find that hydrologic and hydraulic processes govern EC response to diel and seasonal Q variability and that the effects of hyporheic mixing processes on C-Q transience differ in short and long streams. We also observe that variable hyporheic turnover rates govern EC-Q patterns at daily to interannual timescales. Last, subhysteretic analysis reveals a period of interannual freshening of glacial meltwater streams related to the effects of unsteady flow on hyporheic exchange. The subhysteretic analysis framework we introduce may be applied more broadly to constrain the processes controlling C-Q transience and advance understanding of catchment evolution.

  2. High rate lithium-sulfur battery enabled by sandwiched single ion conducting polymer electrolyte.

    Science.gov (United States)

    Sun, Yubao; Li, Gai; Lai, Yuanchu; Zeng, Danli; Cheng, Hansong

    2016-02-22

    Lithium-sulfur batteries are highly promising for electric energy storage with high energy density, abundant resources and low cost. However, the battery technologies have often suffered from a short cycle life and poor rate stability arising from the well-known "polysulfide shuttle" effect. Here, we report a novel cell design by sandwiching a sp(3) boron based single ion conducting polymer electrolyte film between two carbon films to fabricate a composite separator for lithium-sulfur batteries. The dense negative charges uniformly distributed in the electrolyte membrane inherently prohibit transport of polysulfide anions formed in the cathode inside the polymer matrix and effectively blocks polysulfide shuttling. A battery assembled with the composite separator exhibits a remarkably long cycle life at high charge/discharge rates.

  3. High rate lithium-sulfur battery enabled by sandwiched single ion conducting polymer electrolyte

    Science.gov (United States)

    Sun, Yubao; Li, Gai; Lai, Yuanchu; Zeng, Danli; Cheng, Hansong

    2016-01-01

    Lithium-sulfur batteries are highly promising for electric energy storage with high energy density, abundant resources and low cost. However, the battery technologies have often suffered from a short cycle life and poor rate stability arising from the well-known “polysulfide shuttle” effect. Here, we report a novel cell design by sandwiching a sp3 boron based single ion conducting polymer electrolyte film between two carbon films to fabricate a composite separator for lithium-sulfur batteries. The dense negative charges uniformly distributed in the electrolyte membrane inherently prohibit transport of polysulfide anions formed in the cathode inside the polymer matrix and effectively blocks polysulfide shuttling. A battery assembled with the composite separator exhibits a remarkably long cycle life at high charge/discharge rates. PMID:26898772

  4. Strong suppression of impurity accumulation in steady-state hydrogen discharges with high power NBI heating on LHD

    Science.gov (United States)

    Nakamura, Y.; Tamura, N.; Yoshinuma, M.; Suzuki, C.; Yoshimura, S.; Kobayashi, M.; Yokoyama, M.; Nunami, M.; Nakata, M.; Nagaoka, K.; Tanaka, K.; Peterson, B. J.; Ida, K.; Osakabe, M.; Morisaki, T.; the LHD Experiment Group

    2017-05-01

    Strong suppression of impurity accumulation is observed in long pulse hydrogen discharges with high power NBI (neutral beam injection) heating (P nbi  >  10 MW) on the large helical device (LHD), even in the impurity accumulation window where the intrinsic impurities such as Fe and C are always accumulated into the plasma core. Density scan experiments in these discharges demonstrate to vanish the window and a new operational regime without impurity accumulation is found in steady state hydrogen discharges. Impurity pinch decreases with increasing ion temperature gradient and carbon Mach number. The peaking of the measured carbon profiles shows strong anti-correlations with the Mach number and its radial gradient. An external torque has a big impact on impurity transport and strong co-current rotation leads to an extremely hollow carbon profile, so-called ‘impurity hole’ observed in high ion temperature modes. Impurity pinch in the plasmas with net zero torque input (balanced NBI injection) is also strongly reduced by increasing ion temperature gradient, which can drive turbulent modes. The combination effect of turbulence and toroidal rotation plays an important role in the impurity transport.

  5. Measurement and Analysis of Partial Discharge using an Ultra-High Frequency Sensor for Gas Insulated Structures

    Directory of Open Access Journals (Sweden)

    Wang Guoming

    2017-09-01

    Full Text Available Although the gas insulated structures have a high degree of reliability, the unavoidable defects are primary reason of their failures. Partial discharge (PD has been regarded as an effective indication for condition monitoring and diagnosis of gas insulated switchgears (GISs to ensure their reliable and stable operation. Among various PD detection methods, the ultra-high frequency (UHF technique has the advantages of on-line motoring and defect classification. In this paper, there are presented 7 types of artificial electrode systems fabricated for simulation of real insulation defects in gas insulated structures. A real-time measurement system was developed to acquire defect patterns in a form of phase-resolve partial discharge (PRPD intensity graph, using a UHF sensor. Further, the discharge distribution and statistical characteristics were extracted for defect identification using a neural network algorithm. In addition, a conversion experiment was proposed by detecting the PD pulse simultaneously using a non-induction resistor and a UHF sensor. A relationship between the magnitude of UHF signal and the amplitude of apparent charge was established, which was used for evaluation of PD using the UHF sensor.

  6. Comparison of three dielectric barrier discharges regarding their physical characteristics and influence on the adhesion properties on maple, high density fiberboards and wood plastic composite

    Science.gov (United States)

    Peters, F.; Hünnekens, B.; Wieneke, S.; Militz, H.; Ohms, G.; Viöl, W.

    2017-11-01

    In this study, three different dielectric barrier discharges, based on the same setup and run with the same power supply, are characterized by emission spectroscopy with regards to the reduced electrical field strength, and the rotational, vibrational and electron temperature. To compare discharges common for the treatment on wood, a coplanar surface barrier discharge, a direct dielectric barrier discharge and a jet system/remote plasma are chosen. To minimize influences due to the setups or power, the discharges are realized with the same electrodes and power supply and normalized to the same power. To evaluate the efficiency of the different discharges and the influence on treated materials, the surface free energy is determined on a maple wood, high density fiberboard and wood plastic composite. The influence is measured depending on the treatment time, with the highest impact in the time of 5 s.

  7. Regenerative Soot-IX: C3 as the dominant, stable carbon cluster in high pressure sooting discharges

    CERN Document Server

    Janjua, Sohail Ahmad; Khan, S D; Khalid, R; Aleem, A; Ahmad, Shoaib

    2016-01-01

    Results are presented that have been obtained while operating the graphite hollow cathode duoplasmatron ion source in dual mode under constant discharge current. This dual mode operation enabled us to obtain the mass and emission spectra simultaneously. In mass spectra C3 is the main feature but C4 and C5 are also prominent, whereas in emission spectra C2 is also there and its presence shows that it is in an excited state rather than in an ionic state. These facts provide evidence that C3 is produced due to the regeneration of a soot forming sequence and leave it in ionic state. C3 is a stable molecule and the only dominant species among the carbon clusters that survives in a regenerative sooting environment at high-pressure discharges.

  8. Experimental measurements concerning the stator insulation partial discharge level of a hydro-generator of high power

    Science.gov (United States)

    Haţiegan, C.; Răduca, E.; Popescu, C.; Hamat, C. O.; Băra, A.; Anghel, D.; Pîrşan, D. A.

    2018-01-01

    The paper presents a determining and evaluating method from an experimental point of view of the partial discharges level from the insulation of the stator of a synchronous hydro-generator of high power that appear at different temperatures. The temperature is measured directly on the coil with placed thermo-resistant elements between the superior and inferior bars. Also, the level of partial discharges with the coil age in a cold state, at the temperature level of the surrounding environment from within the stator, but also in a warm state at different temperatures, is measured. Through this method there is created the possibility of highlighting some eventual degradations of the coil insulation of a hydro-generator.

  9. Heart bypass surgery - discharge

    Science.gov (United States)

    Off-pump coronary artery bypass - discharge; OPCAB - discharge; Beating heart surgery - discharge; Bypass surgery - heart - discharge; CABG - discharge; Coronary artery bypass graft - discharge; Coronary artery ...

  10. Factors Associated With the Increasing Rates of Discharges Directly Home From Intensive Care Units-A Direct From ICU Sent Home Study.

    Science.gov (United States)

    Lau, Vincent I; Priestap, Fran A; Lam, Joyce N H; Ball, Ian M

    2016-09-20

    To evaluate the relationship between rates of discharge directly to home (DDH) from the intensive care unit (ICU) and bed availability (ward and ICU). Also to identify patient characteristics that make them candidates for safe DDH and describe transfer delay impact on length of stay (LOS). Retrospective cohort study of all adult patients who survived their stay in our medical-surgical-trauma ICU between April 2003 and March 2015. Median age was 49 years (interquartile range [IQR]: 33.5-60.4), and the majority of the patients were males (54.8%). Median number of preexisting comorbidities was 5 (IQR: 2-7) diagnoses. Discharge directly to home increased from 28 (3.1% of all survivors) patients in 2003 to 120 (12.5%) patients in 2014. The mean annual rate of DDH was between 11% and 12% over the last 6 years. Approximately 62% (n = 397) of patients waited longer than 4 hours for a ward bed, with a median delay of 2.0 days (IQR: 0.5-4.7) before being DDH. There was an inverse correlation between ICU occupancy and DDH rates (r P = -.55, P ICU bed occupancy but were not associated with ward occupancy. The DDH patients are young, have few comorbidities on admission, and few discharge diagnoses, which are usually reversible single system problems with low disease burden. Transfers to the ward are delayed in a majority of cases, leading to increased ICU LOS and likely increased overall hospital LOS as well. © The Author(s) 2016.

  11. Sympathetic-induced changes in discharge rate and spike-triggered average twitch torque of low-threshold motor units in humans.

    Science.gov (United States)

    Roatta, Silvestro; Arendt-Nielsen, Lars; Farina, Dario

    2008-11-15

    Animal and in vitro studies have shown that the sympathetic nervous system modulates the contractility of skeletal muscle fibres, which may require adjustments in the motor drive to the muscle in voluntary contractions. In this study, these mechanisms were investigated in the tibialis anterior muscle of humans during sympathetic activation induced by the cold pressor test (CPT; left hand immersed in water at 4 degrees C). In the first experiment, 11 healthy men performed 20 s isometric contractions at 10% of the maximal torque, before, during and after the CPT. In the second experiment, 12 healthy men activated a target motor unit at the minimum stable discharge rate for 5 min in the same conditions as in experiment 1. Intramuscular electromyographic (EMG) signals and torque were recorded and used to assess the motor unit discharge characteristics (experiment 1) and spike-triggered average twitch torque (experiment 2). CPT increased the diastolic blood pressure and heart rate by (mean +/- S.D.) 18 +/- 9 mmHg and 4.7 +/- 6.5 beats min(-1) (P < 0.01), respectively. In experiment 1, motor unit discharge rate increased from 10.4 +/- 1.0 pulses s(-1) before to 11.1 +/- 1.4 pulses s(-1) (P < 0.05) during the CPT. In experiment 2, the twitch half-relaxation time decreased by 15.8 +/- 9.3% (P < 0.05) during the CPT with respect to baseline. These results provide the first evidence of an adrenergic modulation of contractility of muscle fibres in individual motor units in humans, under physiological sympathetic activation.

  12. Measuring health literate discharge practices.

    Science.gov (United States)

    Innis, Jennifer; Barnsley, Jan; Berta, Whitney; Daniel, Imtiaz

    2017-02-13

    Purpose Health literate discharge practices meet patient and family health literacy needs in preparation for care transitions from hospital to home. The purpose of this paper is to measure health literate discharge practices in Ontario hospitals using a new organizational survey questionnaire tool and to perform psychometric testing of this new survey. Design/methodology/approach This survey was administered to hospitals in Ontario, Canada. Exploratory factor analysis and reliability testing were performed. Findings The participation rate of hospitals was 46 percent. Exploratory factor analysis demonstrated that there were five factors. The survey, and each of the five factors, had moderate to high levels of reliability. Research limitations/implications There is a need to expand the focus of further research to examine the experiences of patients and families. Repeating this study with a larger sample would facilitate further survey development. Practical implications Measuring health literate discharge practices with an organizational survey will help hospital managers to understand their performance and will help direct quality improvement efforts to improve patient care at hospital discharge and to decrease hospital readmission. Originality/value There has been little research into how patients are discharged from hospital. This study is the first to use an organizational survey tool to measure health literate discharge practices.

  13. Using heart rate "Sigma sport 1300" in the operational control of special endurance cyclists of higher discharges (for example, cross-country

    Directory of Open Access Journals (Sweden)

    Voropay Sergej Nikolaevich

    2011-11-01

    Full Text Available It is shown the efficiency of the use of «Sigma Sport 1300» in operational control of special endurance athletes. The study involved 10 athletes of higher discharges. At baseline for each athlete was defined range of indicators of heart rate and intensity of the zone. It is established that the best indicators of changes in special endurance observed in the control of the intensity of objective internal performance. It is noted that the subjective assessment can be influenced by many extraneous factors: the cumulative effect of exercise, emotional athlete to the start of classes.

  14. Miniature High Stability High Temperature Space Rated Blackbody Radiance Source

    Science.gov (United States)

    Jones, J. A.; Beswick, A. G.

    1987-09-01

    This paper presents the design and test performance of a conical cavity type blackbody radiance source that will meet the requirements of the Halogen Occultation Experiment (HALOE) on the NASA Upper Atmospheric Research Satellite program (UARS). Since a radiance source meeting the requirements of this experiment was unavailable in the commercial market, a development effort was undertaken by the HALOE Project. The blackbody radiance source operates in vacuum at 1300 K + 0.5 K over any 15-minute interval, uses less than 7.5 watts of power, maintains a 49°C outer case temperature, and fits within the 2.5 x 2.5 x 3.0 inch envelope allocated inside the HALOE instrument. Also, the unit operates in air, during ground testing of the HALOE instrument, where it uses 17 watts of power with an outer case temperature of 66°C. The thrust of this design effort was to minimize the heat losses, in order to keep the power usage under 7.5 watts, and to minimize the amount of silica in the materials. Silica in the presence of the platinum heater winding used in this design would cause the platinum to erode, changing the operating temperature set-point. The design required the development of fabrication techniques which would provide very small, close tolerance parts from extremely difficult-to-machine materials. Also, a space rated ceramic core and unique, low thermal conductance, ceramic-to-metal joint was developed, tested and incorporated in this design. The completed flight qualification hardware has undergone performance, environmental and life testing. The design configuration and test results are discussed in detail in this paper.

  15. Technology of discharge and laser resonators for high power CO2 lasers. Koshutsuryoku CO2 laser ni tsukawareru hoden reiki laser kyoshinki gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Takenaka, Y.; Kuzumoto, M. (Mitsubishi Electric Corp., Tokyo (Japan))

    1994-03-20

    This paper describes discharge excitation technology and resonator technology as basic technologies for high power CO2 lasers. As a result of progress in high-frequency power element techniques, the discharge excitation technology now generally uses laser excitation using AC discharge of capacity coupling type. Its representative example is silent discharge (SD) excitation. This is a system to excite laser by applying high voltages with as high frequency as 100 kHz to 1 MHz across a pair of electrodes covered with a dielectric material. The system maintains stability in discharge even if power supply voltage amplitude is modulated, and easily provides pulse outputs. Discharge excitation for diffusion cooled type CO2 laser generates a discharge in a gap with a gap length of about 2 mm, and can perform gas cooling by means of thermal conduction of gas, whereas a compact resonator can be fabricated. A resonator for the diffusion cooled type CO2 laser eliminates gas circulation and cooling systems, hence the device can be made more compact. A report has been given that several of these compact resonators were combined, from which a laser output of 85W was obtained by using RF discharge of 2kW. 43 refs., 21 figs.

  16. Bronchiolitis - discharge

    Science.gov (United States)

    RSV bronchiolitis - discharge; Respiratory syncytial virus bronchiolitis - discharge ... Your child has bronchiolitis , which causes swelling and mucus to build up in the smallest air passages of the lungs. In the hospital, ...

  17. Angina - discharge

    Science.gov (United States)

    ... also learn how to take care of your heart disease . Diet and lifestyle Try to limit how much alcohol ... surgery - discharge Heart bypass surgery - minimally invasive - discharge Heart disease - risk ... Review Date 8/2/2016 Updated by: Michael ...

  18. High-photosensitivity a-SiGe: H films prepared by RF glow discharge plasma CVD method

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Fangqing (Dept. of Physics, Lanzhou Univ. (China)); Song Zhizhong (Dept. of Physics, Lanzhou Univ. (China)); Guo Yongping (Dept. of Physics, Lanzhou Univ. (China)); Chen Guanghua (Dept. of Physics, Lanzhou Univ. (China))

    1993-04-01

    Highly photosensitive and narrow band gap a-SiGe:H films have been prepared by the RF glow discharge plasma CVD method. The photosensitivity was 2.01x10[sup 5] for the film with an optical band gap of E[sub g]=1.47 eV. H[sub 2] dilution and a relatively high RF power are attributed to the improving of the optoelectrical properties. Thermally induced changes of the a-SiGe:H films have been also investigated. (orig.)

  19. Combined mesophilic anaerobic and thermophilic aerobic digestion process for high-strength food wastewater to increase removal efficiency and reduce sludge discharge.

    Science.gov (United States)

    Jang, H M; Park, S K; Ha, J H; Park, J M

    2014-01-01

    In this study, a process that combines the mesophilic anaerobic digestion (MAD) process with thermophilic aerobic digestion (TAD) for high-strength food wastewater (FWW) treatment was developed to examine the removal of organic matter and methane production. All effluent discharged from the MAD process was separated into solid and liquid portions. The liquid part was discarded and the sludge part was passed to the TAD process for further degradation. Then, the digested sludge from the TAD process was recycled back to the MAD unit to achieve low sludge discharge from the combined process. The reactor combination was operated in two phases: during Phase I, 40 d of total hydraulic retention time (HRT) was applied; during Phase II, 20 d was applied. HRT of the TAD process was fixed at 5 d. For a comparison, a control process (single-stage MAD) was operated with the same HRTs of the combined process. Our results indicated that the combined process showed over 90% total solids, volatile solids and chemical oxygen demand removal efficiencies. In addition, the combined process showed a significantly higher methane production rate than that of the control process. Consequently, the experimental data demonstrated that the combined MAD-TAD process was successfully employed for high-strength FWW treatment with highly efficient organic matter reduction and methane production.

  20. Effect of air flow on the micro-discharge dynamics in an array of integrated coaxial microhollow dielectric barrier discharges

    Science.gov (United States)

    Nayak, Gaurav; Du, Yanjun; Brandenburg, Ronny; Bruggeman, Peter J.

    2017-03-01

    The micro-discharge properties and evolution in a 2D array of integrated coaxial microhollow dielectric barrier discharges are studied by using highly time-resolved electrical and optical diagnostics. The study is focused on the effect of the gas flow rate and gas residence time on discharge properties. The investigated integrated coaxial microhollow discharge geometry allows operating the discharge at exceptionally small residence times, which can be equal to or even smaller than the discharge period, at reasonable gas flow rates. The gas flow has an impact on gas heating, residual humidity, pre-ionization density and the densities of excited and reactive species produced by previous discharges. A unique voltage-charge plot is obtained with elongated periods without discharge activity. A very significant effect of flow on NO emission is observed that relates to the impact of flow on the NO production in these micro-discharges. Using the emission intensities of molecular bands of the second positive system of nitrogen and the first negative system of the nitrogen ion, effective reduced electric field strengths are obtained with a maximum equal to 870 Td. The reduced electric field decreases with increasing gas flow rate. This behavior is consistent with the reduction of the overall discharge intensity due to a reduced amount of charges present in the discharge gap. Both the flow rate and a reduction in water impurity changing the ion mobility can be responsible for the different effective electric field distributions at the highest and no flow conditions.

  1. Thermal-sprayed, thin-film pyrite cathodes for thermal batteries -- Discharge-rate and temperature studies in single cells

    Energy Technology Data Exchange (ETDEWEB)

    GUIDOTTI,RONALD A.; REINHARDT,FREDERICK W.; DAI,JINXIANG; XIAO,T. DANNY; REISNER,DAVID

    2000-05-25

    Using an optimized thermal-spray process, coherent, dense deposits of pyrite (FeS{sub 2}) with good adhesion were formed on 304 stainless steel substrates (current collectors). After leaching with CS{sub 2} to remove residual free sulfur, these served as cathodes in Li(Si)/FeS{sub 2} thermal cells. The cells were tested over a temperature range of 450 C to 550 C under baseline loads of 125 and 250 mA/cm{sup 2}, to simulate conditions found in a thermal battery. Cells built with such cathodes outperformed standard cells made with pressed-powder parts. They showed lower interracial resistance and polarization throughout discharge, with higher capacities per mass of pyrite. Post-treatment of the cathodes with Li{sub 2}O coatings at levels of >7% by weight of the pyrite was found to eliminate the voltage transient normally observed for these materials. Results equivalent to those of standard lithiated catholytes were obtained in this manner. The use of plasma-sprayed cathodes allows the use of much thinner cells for thermal batteries since only enough material needs to be deposited as the capacity requirements of a given application demand.

  2. Tesla coil discharges guided by femtosecond laser filaments in air

    OpenAIRE

    Brelet, Yohann; Houard, Aurélien; Arantchouk, Leonid; Forestier, Benjamin; Liu, Yi; Prade, Bernard; Carbonnel, Jérôme; André, Yves-Bernard; Mysyrowicz, André

    2012-01-01

    International audience; A Tesla coil generator was designed to produce high voltage pulses oscillating at 100 kHz synchronisable with a nanosecond temporal jitter. Using this compact high voltage generator, we demonstrate reproducible meter long discharges in air at a repetition rate of 1 Hz. Triggering and guiding of the discharges are performed in air by femtosecond laser filaments.

  3. Tesla coil discharges guided by femtosecond laser filaments in air

    Science.gov (United States)

    Brelet, Yohann; Houard, Aurélien; Arantchouk, Leonid; Forestier, Benjamin; Liu, Yi; Prade, Bernard; Carbonnel, Jérôme; André, Yves-Bernard; Mysyrowicz, André

    2012-04-01

    A Tesla coil generator was designed to produce high voltage pulses oscillating at 100 kHz synchronisable with a nanosecond temporal jitter. Using this compact high voltage generator, we demonstrate reproducible meter long discharges in air at a repetition rate of 1 Hz. Triggering and guiding of the discharges are performed in air by femtosecond laser filaments.

  4. Image Enhancement for High frame-rate Neutron Radiography

    OpenAIRE

    Saito, Y; Ito, D.

    2015-01-01

    High frame rate neutron radiography has been utilized to investigate two-phase flow in a metallic duct. However, images obtained by high frame-rate neutron radiography suffered from severe statistical noise due to its short exposure time. In this study, a spatio-temporal filter was applied to reduce the noise in the sequence images obtained by high frame-rate neutron radiography. Experiments were performed at the B4-port of the Research Reactor Institute, Kyoto University, which has a thermal...

  5. Development of High Efficiency Versatile Arc Discharge Ion Source (VADIS) at CERN Isolde

    CERN Document Server

    Penescu, L; Lettry, J; Stora, T

    2010-01-01

    We report here recent developments of Forced Electron Beam Impact Arc Discharge (FEBIAD) ion sources at CERN-ISOLDE. As a result of the propositions to improve the ionization efficiency, two FEBIAD prototypes have been produced and successfully tested in 2008. Off-line studies showed that the 1+ ionization efficiencies for noble gases are 5 to 20 times larger than with the standard ISOLDE FEBIAD ion sources, and reach 60% for Radon, which allowed the identification at ISOLDE of 229Rn, an isotope that had never previously been observed in the laboratory. A factor 3 increase is also expected for the ionization efficiency of the other elements. The experimental and theoretical methodology is presented. The theoretical model which gives precise insights on the processes affecting the ionization is used to design optimal sources for the different chemical classes of the produced isotopes, as already demonstrated for noble gases.

  6. Supershort avalanche electron beams and x-ray in high-pressure nanosecond discharges

    Science.gov (United States)

    Tarasenko, V. F.; Baksht, E. H.; Kostyrya, I. D.; Lomaev, M. I.; Rybka, D. V.

    2008-10-01

    The properties of a supershort avalanche electron beam (S AEB) and X-ray radiation produced using a nanosecond volume discharge are examined. An electron beam of the runaway electrons with amplitude of ~ 50 A has been obtained in air atmospheric pressure. It is reported that S AEB is formed in the angle above 2π sr. Three groups of the runaway electrons are formed in a gas diode under atmospheric air pressure, when nanosecond voltage pulses with amplitude of hundreds of kilovolts are applied. The electron beam has been generated behind a 45 μm thick AlBe foil in SF6 and Xe under the pressure of 2 arm, and in He under the pressure of about 12 atm. The paper gives the analysis of a generation mechanism of SAEB.

  7. Infrared gas phase study on plasma-polymer interactions in high-current diffuse dielectric barrier discharge

    Science.gov (United States)

    Liu, Y.; Welzel, S.; Starostin, S. A.; van de Sanden, M. C. M.; Engeln, R.; de Vries, H. W.

    2017-06-01

    A roll-to-roll high-current diffuse dielectric barrier discharge at atmospheric pressure was operated in air and Ar/N2/O2 gas mixtures. The exhaust gas from the discharge was studied using a high-resolution Fourier-transform infrared spectrometer in the range from 3000 to 750 cm-1 to unravel the plasma-polymer interactions. The absorption features of HxNyOz, COx, and HCOOH (formic acid) were identified, and the relative densities were deduced by fitting the absorption bands of the detected molecules. Strong interactions between plasma and polymer (Polyethylene-2,6-naphthalate, or PEN) in precursor-free oxygen-containing gas mixtures were observed as evidenced by a high COx production. The presence of HCOOH in the gas effluent, formed through plasma-chemical synthesis of COx, turns out to be a sensitive indicator for etching. By adding tetraethylorthosilicate precursor in the plasma, dramatic changes in the COx production were measured, and two distinct deposition regimes were identified. At high precursor flows, a good agreement with the precursor combustion and the COx production was observed, whereas at low precursor flows an etching-deposition regime transpires, and the COx production is dominated by polymer etching.

  8. Cardiac catheterization - discharge

    Science.gov (United States)

    Catheterization - cardiac - discharge; Heart catheterization - discharge: Catheterization - cardiac; Heart catheterization; Angina - cardiac catheterization discharge; CAD - cardiac catheterization discharge; Coronary ...

  9. Electric discharge microplasmas generated in highly fluctuating fluids: Characteristics and application to the synthesis of molecular diamond

    Science.gov (United States)

    Stauss, Sven

    2014-10-01

    Plasma-based fabrication of novel nanomaterials and nanostructures is paramount for the development of next-generation electronic devices and for green energy applications. In particular, controlling the interactions between plasmas and materials interfaces, and the plasma fluctuations are crucial for further development of plasma-based processes and bottom-up growth of nanomaterials. Discharge microplasmas generated in supercritical fluids represent a special class of high-pressure plasmas, where fluctuations on the molecular scale influence the discharge properties and the possible bottom-up growth of nanomaterials. In the first part of the talk, we will discuss an anomaly observed for microplasmas generated near the critical point, a local decrease in the breakdown voltage, which has been observed for both molecular and monoatomic gases. This anomalous behavior is suggested to be caused by the concomitant decrease of the ionization potential due to the formation of clusters near the critical point, and the formation of extended electron mean free paths induced by the high-density fluctuation near the critical point. We will also show that when generating microplasma discharges close to the critical point, that the high-density fluctuation of the supercritical fluid persists. In the second part of the presentation, we will first introduce the basic properties of diamondoids and their potential for application in many different fields - biotechnology, medicine, opto- and nanoelectronics - before discussing their synthesis by microplasmas generated inside both conventional batch-type and continuous flow reactors, using the smallest diamondoid, adamantane, as a precursor and seed. Finally we show that one possible growth mechanism of larger diamondoids from smaller ones consists in the repeated abstraction of hydrogen terminations and the addition of methyl radicals. Supported financially in part by Grant No. 23760688 and Grant No. 21110002 from the Ministry of

  10. Transit dose calculation in high dose rate brachytherapy (HDR ...

    African Journals Online (AJOL)

    Transit doses around a high dose rate 192Ir brachytherapy source were calculated using Sievert Integral at positions where the moving source was located exactly between two adjacent dwell positions. The correspond-ing transit dose rates were obtained by using energy absorption coefficients. Discrete step sizes of 0.25 ...

  11. Rural and Urban High School Dropout Rates: Are They Different?

    Science.gov (United States)

    Jordan, Jeffrey L.; Kostandini, Genti; Mykerezi, Elton

    2012-01-01

    This study estimates the high school dropout rate in rural and urban areas, the determinants of dropping out, and whether the differences in graduation rates have changed over time. We use geocoded data from two nationally representative panel household surveys (NLSY 97 and NLSY 79) and a novel methodology that corrects for biases in graduation…

  12. Pedalling rate affects endurance performance during high-intensity cycling

    DEFF Research Database (Denmark)

    Nielsen, Jens Steen; Hansen, Ernst Albin; Sjøgaard, Gisela

    2004-01-01

    The purpose of this study into high-intensity cycling was to: (1) test the hypothesis that endurance time is longest at a freely chosen pedalling rate (FCPR), compared to pedalling rates 25% lower (FCPR-25) and higher (FCPR+25) than FCPR, and (2) investigate how physiological variables, such as m...

  13. Properties and etching rates of negative ions in inductively coupled plasmas and dc discharges produced in Ar/SF6

    DEFF Research Database (Denmark)

    Draghici, Mihai; Stamate, Eugen

    2010-01-01

    of negative ion to electron exceeded 300 in dc mode while it was below 100 in the ICP mode. The possibility to apply a large positive bias to an electrode without affecting the plasma potential and the transition from a negative sheath to anodic glow are also investigated. The etching rates by positive...... and negative ions are evaluated on silicon substrate for different Ar/SF6 gas ratios. The etching rate by negative ions was with less than 5% smaller than that by positive ions....

  14. High Count Rate Single Photon Counting Detector Array Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An optical communications receiver requires efficient and high-rate photon-counting capability so that the information from every photon, received at the aperture,...

  15. CASSINI HIGH RATE DETECTOR V17.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  16. CASSINI HIGH RATE DETECTOR V2.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  17. CASSINI HIGH RATE DETECTOR V12.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  18. CASSINI HIGH RATE DETECTOR V8.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  19. CASSINI HIGH RATE DETECTOR V10.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  20. CASSINI HIGH RATE DETECTOR V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  1. CASSINI HIGH RATE DETECTOR V13.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  2. CASSINI HIGH RATE DETECTOR V9.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  3. CASSINI HIGH RATE DETECTOR V3.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  4. CASSINI HIGH RATE DETECTOR V7.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  5. CASSINI HIGH RATE DETECTOR V4.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  6. CASSINI HIGH RATE DETECTOR V11.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  7. CASSINI HIGH RATE DETECTOR V14.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  8. CASSINI HIGH RATE DETECTOR V5.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  9. CASSINI HIGH RATE DETECTOR V6.0

    Data.gov (United States)

    National Aeronautics and Space Administration — The High Rate Detector (HRD) from the University of Chicago is an independent part of the CDA instrument on the Cassini Orbiter that measures the dust flux and...

  10. High Burn Rate Hybrid Fuel for Improved Grain Design Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A novel type of fuel providing high burning rate for hybrid rocket applications is proposed. This fuel maintains a hydrodynamically rough surface to...

  11. Preparation of carbon-encapsulated iron nanoparticles in high yield by DC arc discharge and their characterization

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fan [Department of Chemistry, School of Science, Tianjin University, Tianjin 300072 (China); Cui, Lan; Lin, Kui [Center of Analysis, Tianjin University, Tianjin 300072 (China); Jin, Feng-min; Wang, Bin [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Shi, Shu-xiu [Department of Chemistry, School of Science, Tianjin University, Tianjin 300072 (China); Yang, De-an [School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China); Wang, Hui [Center of Analysis, Tianjin University, Tianjin 300072 (China); He, Fei [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Chen, Xiao-ping [Center of Analysis, Tianjin University, Tianjin 300072 (China); Cui, Shen, E-mail: cuishen@tju.edu.cn [Department of Chemistry, School of Science, Tianjin University, Tianjin 300072 (China)

    2013-03-15

    Highlights: ► CEINPs with core–shell structure and high Fe content were prepared in high yield by DC arc discharge. ► The anode II with a mass ratio of total iron to carbon 8:1 was used in DC arc discharge. ► The possible process of formation of CEINPs is briefly discussed. ► The uniformity of composition of anode is very important for the formation of CEINPs. ► The MEF and MMF of iron element may also play an important role in the formation of CEINPs. -- Abstract: Carbon-encapsulated iron nanoparticles (CEINPs) were prepared by DC arc discharge under nitrogen atmosphere of high temperature. The products were characterized by transmission electron microscope (TEM), high-resolution transmission electron microscope (HRTEM), X-ray diffractometer (XRD), energy dispersive X-ray (EDX) spectroscope, and X-ray photoelectron spectroscope (XPS), and their magnetic properties were measured by physical property measurement system (PPMS). The product B{sub I}, obtained from the anode I, contains the nanoparticles of iron and iron carbide, and carbon coating with imperfect and disordered layer structure. The product B{sub II}, obtained from the anode II, mainly consists of CEINPs, whose cores mainly consist of iron and iron carbide and shells contain about 3–7 graphitic layers. The iron contents in the products B{sub I} and B{sub II} are 44.8 and 82.6 wt.%, respectively. The products B{sub I} and B{sub II} have similar phase composition which includes carbon, iron, iron carbide, ferrous and ferric oxide, iron nitride, and carbon nitride. The saturation magnetization (Ms) of the products B{sub I} and B{sub II} are 29.35 and 88.66 emu/g and their coercivity (Hc) are 220 and 240 Oe, respectively. The total yields of all the products formed in the arc discharge chamber from anodes I and II, except for the cylinder-shaped deposits formed on the top of the cathode, are 25.8 and 22.3 wt.%, respectively. The possible process of formation of CEINPs is briefly discussed on

  12. Mozart K.448 attenuates spontaneous absence seizure and related high-voltage rhythmic spike discharges in Long Evans rats.

    Science.gov (United States)

    Lin, Lung-Chang; Juan, Chun-Ting; Chang, Hsueh-Wen; Chiang, Ching-Tai; Wei, Ruey-Chang; Lee, Mei-Wen; Mok, Hin-Kiu; Yang, Rei-Cheng

    2013-05-01

    Recent research has revealed more evidence supporting the positive effects of music on humans and animals. However, evidence of music's effects on improving epilepsy in animals is sparse. This study aimed to clarify the influence of Mozart's music in Long Evans rats, which are characterized by spontaneous absence epilepsy (SAE) and high-voltage rhythmic spike (HVRS) discharges. Continuous electroencephalograms comprised of HVRS discharges, and behavioral performance were recorded in Long Evans rats (n=5) before, during, and after exposure to the Mozart's Sonata for Two Pianos in D Major, K.448 (Mozart K.448). The same evaluation was repeated after they had been subjected to daily exposure of the music for 20 days. Seizure frequencies and spontaneous HVRS discharges were reduced in all of the SAE rats during and after music exposure compared with the pre-music stage. The average seizure frequencies were 79.8±24.6, 48±15.2, and 33±12.1/h before, during, and after music exposure, respectively. The average run of spike episodes were 84.6±18.4, 52±17.8, and 36.8±16.9/h before, during, and after music exposure, respectively. The seizure frequencies and related run of spike episodes decreased by 39.8% and 38.5% during, and 58.6% and 56.6% post music exposure, respectively. The average run of spike durations and spike numbers also showed significant decreases (reduction by 47.1%, 47.8% during music and 60.8%, 61.3% post music). After daily music exposure for 20 days, the number of HVRS discharges and seizure frequencies during and after music exposure, however, showed no further accumulative reduction or adaptation effect. These results suggest that Mozart K.448 had a positive short-term effect in attenuating the spontaneous HVRS discharges in Long Evans rats. However, the mechanism needs further investigation. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Quantum Communication with a High-Rate Entangled Photon Source

    Science.gov (United States)

    Wilson, Nathaniel C.; Chaffee, Dalton W.; Lekki, John D.; Wilson, Jeffrey D.

    2016-01-01

    A high generation rate photon-pair source using a dual element periodically-poled potassium titanyl phosphate (PP KTP) waveguide is described. The photon-pair source features a high pair generation rate, a compact power-efficient package, and continuous wave (CW) or pulsed operation. Characterization and test results are presented. Details and preliminary results of a laboratory free-space QKD experiment with the B92 protocol are also presented.

  14. The Relationship between Toxics Release Inventory Discharges and Mortality Rates in Rural and Urban Areas of the United States

    Science.gov (United States)

    Hendryx, Michael; Fedorko, Evan

    2011-01-01

    Background: Potential environmental exposures from chemical manufacturing or industrial sites have not been well studied for rural populations. The current study examines whether chemical releases from facilities monitored through the Toxics Release Inventory (TRI) program are associated with population mortality rates for both rural and urban…

  15. A rate-dependent Hosford-Coulomb model for predicting ductile fracture at high strain rates

    Directory of Open Access Journals (Sweden)

    Marcadet Stephane J.

    2015-01-01

    Full Text Available The Hosford-Coulomb model incorporates the important effect of the Lode angle parameter in addition to the stress triaxiality to predict the initiation of ductile fracture. A strain-rate dependent extension of the Hosford-Coulomb model is presented to describe the results from low, intermediate and high strain rate fracture experiments on advanced high strength steels (DP590 and TRIP780. The model predictions agree well with the experimental observation of an increase in ductility as function of strain rate for stress states ranging from uniaxial to equi-biaxial tension.

  16. High strain rate response of rabbit femur bones.

    Science.gov (United States)

    Shunmugasamy, Vasanth Chakravarthy; Gupta, Nikhil; Coelho, Paulo G

    2010-11-16

    Strain rate dependence of the mechanical response of hard tissues has led to a keen interest in their dynamic properties. The current study attempts to understand the high strain rate characteristics of rabbit femur bones. The testing was conducted using a split-Hopkinson pressure bar equipped with a high speed imaging system to capture the fracture patterns. The bones were also characterized under quasi-static compression to enable comparison with the high strain rate results. The quasi-static compressive moduli of the epiphyseal and diaphyseal regions were measured to be in the range of 2-3 and 5-7GPa, respectively. Under high strain rate loading conditions the modulus is observed to increase with strain rate and attains values as high as 15GPa for epiphyseal and 30GPa for diaphyseal regions of the femur. The strength at high strain rate was measured to be about twice the quasi-static strength value. A large number of small cracks initiated on the specimen surface close to the incident bar. Coalescence of crack branches leading to fewer large cracks resulted in specimen fragmentation. In comparison, the quasi-static failure was due to shear cracking. Copyright © 2010 Elsevier Ltd. All rights reserved.

  17. Performance of high flow rate samplers for respirable particle collection.

    Science.gov (United States)

    Lee, Taekhee; Kim, Seung Won; Chisholm, William P; Slaven, James; Harper, Martin

    2010-08-01

    The American Conference of Governmental Industrial hygienists (ACGIH) lowered the threshold limit value (TLV) for respirable crystalline silica (RCS) exposure from 0.05 to 0.025 mg m(-3) in 2006. For a working environment with an airborne dust concentration near this lowered TLV, the sample collected with current standard respirable aerosol samplers might not provide enough RCS for quantitative analysis. Adopting high flow rate sampling devices for respirable dust containing silica may provide a sufficient amount of RCS to be above the limit of quantification even for samples collected for less than full shift. The performances of three high flow rate respirable samplers (CIP10-R, GK2.69, and FSP10) have been evaluated in this study. Eleven different sizes of monodisperse aerosols of ammonium fluorescein were generated with a vibrating orifice aerosol generator in a calm air chamber in order to determine the sampling efficiency of each sampler. Aluminum oxide particles generated by a fluidized bed aerosol generator were used to test (i) the uniformity of a modified calm air chamber, (ii) the effect of loading on the sampling efficiency, and (iii) the performance of dust collection compared to lower flow rate cyclones in common use in the USA (10-mm nylon and Higgins-Dewell cyclones). The coefficient of variation for eight simultaneous samples in the modified calm air chamber ranged from 1.9 to 6.1% for triplicate measures of three different aerosols. The 50% cutoff size ((50)d(ae)) of the high flow rate samplers operated at the flow rates recommended by manufacturers were determined as 4.7, 4.1, and 4.8 microm for CIP10-R, GK2.69, and FSP10, respectively. The mass concentration ratio of the high flow rate samplers to the low flow rate cyclones decreased with decreasing mass median aerodynamic diameter (MMAD) and high flow rate samplers collected more dust than low flow rate samplers by a range of 2-11 times based on gravimetric analysis. Dust loading inside the

  18. Stretching of red blood cells at high strain rates

    Science.gov (United States)

    Mancuso, J. E.; Ristenpart, W. D.

    2017-10-01

    Most work on the mechanical behavior of red blood cells (RBCs) in flow has focused on simple shear flows. Relatively little work has examined RBC deformations in the physiologically important extensional flow that occurs at the entrance to a constriction. In particular, previous work suggests that RBCs rapidly stretch out and then retract upon entering the constriction, but to date no model predicts this behavior for the extremely high strain rates typically experienced there. In this Rapid Communication, we use high speed video to perform systematic measurements of the dynamic stretching behavior of RBCs as they enter a microfluidic constriction. We demonstrate that both the Kelvin-Voigt and Skalak viscoelastic models capture the observed stretching dynamics, up to strain rates as high as 2000 s-1. The results indicate that the effective elastic modulus of the RBC membrane at these strain rates is an order of magnitude larger than moduli measured by micropipette aspiration or other low strain rate techniques.

  19. Solidification at the High and Low Rate Extreme

    Energy Technology Data Exchange (ETDEWEB)

    Meco, Halim [Iowa State Univ., Ames, IA (United States)

    2004-12-19

    The microstructures formed upon solidification are strongly influenced by the imposed growth rates on an alloy system. Depending on the characteristics of the solidification process, a wide range of growth rates is accessible. The prevailing solidification mechanisms, and thus the final microstructure of the alloy, are governed by these imposed growth rates. At the high rate extreme, for instance, one can have access to novel microstructures that are unattainable at low growth rates. While the low growth rates can be utilized for the study of the intrinsic growth behavior of a certain phase growing from the melt. Although the length scales associated with certain processes, such as capillarity, and the diffusion of heat and solute, are different at low and high rate extremes, the phenomena that govern the selection of a certain microstructural length scale or a growth mode are the same. Consequently, one can analyze the solidification phenomena at both high and low rates by using the same governing principles. In this study, we examined the microstructural control at both low and high extremes. For the high rate extreme, the formation of crystalline products and factors that control the microstructure during rapid solidification by free-jet melt spinning are examined in Fe-Si-B system. Particular attention was given to the behavior of the melt pool at different quench-wheel speeds. Since the solidification process takes place within the melt-pool that forms on the rotating quench-wheel, we examined the influence of melt-pool dynamics on nucleation and growth of crystalline solidification products and glass formation. High-speed imaging of the melt-pool, analysis of ribbon microstructure, and measurement of ribbon geometry and surface character all indicate upper and lower limits for melt-spinning rates for which nucleation can be avoided, and fully amorphous ribbons can be achieved. Comparison of the relevant time scales reveals that surface-controlled melt

  20. Metallurgical applications of shock wave and high strain rate phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Murr, L.E.; Staudhammer, K.P.; Meyers, M.A.

    1986-01-01

    This book presents the papers given at a conference on the impact testing of metals. Topics considered at the conference included dynamic consolidation, the analysis of dislocation kinetics across shocks, high-strain-rate deformation, adiabatic shear band phenomena, dynamic fracture, explosive metal working, shock synthesis and the property modification of materials, and novel concepts and applications of high pressure.

  1. High flow rate microsieve for bio medical applications

    NARCIS (Netherlands)

    van Rijn, C.J.M.; Nijdam, W.; Elwenspoek, Michael Curt

    1995-01-01

    A new composite filtration membrane having a thin filtration or sieving layer has been developed. This filtration membrane with a high pore density and a narrow pore size distribution on a macro porous support shows good separation behaviour and a high flow rate. Because of the construction method,

  2. Authoritative School Climate and High School Dropout Rates

    Science.gov (United States)

    Jia, Yuane; Konold, Timothy R.; Cornell, Dewey

    2016-01-01

    This study tested the association between school-wide measures of an authoritative school climate and high school dropout rates in a statewide sample of 315 high schools. Regression models at the school level of analysis used teacher and student measures of disciplinary structure, student support, and academic expectations to predict overall high…

  3. Performance of the Ultra-High Rate Germanium (UHRGe) System

    Energy Technology Data Exchange (ETDEWEB)

    Fast, James E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dion, Michael P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rodriguez, Douglas C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); VanDevender, Brent A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wood, Lynn S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wright, Michael E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-12-01

    This report describes the final performance achieved with the detector system developed for the Ultra High Rate Germanium (UHRGe) project. The system performance has been evaluated at low, moderate and high rates and includes the performance of real-time analysis algorithms running in the FPGA of the data acquisition system. This performance is compared to that of offline analyses of streaming waveform data collected with the same data acquisition system the performance of a commercial Multi-Channel Analyzer designed for high-resolution spectroscopy applications, the Canberra LYNX.

  4. Breakdown Limit Studies in High Rate Gaseous Detectors

    CERN Document Server

    Ivaniouchenkov, Yu; Peskov, Vladimir; Ramsey, B D

    1998-01-01

    We report results from a systematic study of breakdown limits for novel high rate gaseous detectors: MICROMEGAS, CAT and GEM, together with more conventional devices such as thin-gap parallel-mesh chambers and high-rate wire chambers. It was found that for all these detectors, the maximum achievable gain, before breakdown appears, drops dramatically with incident flux, and is sometimes inversely proportional to it. Further, in the presence of alpha particles, typical of the backgrounds in high-energy experiments, additional gain drops of 1-2 orders of magnitude were observed for many detectors. It was found that breakdowns at high rates occur through what we have termed an "accumulative" mechanism, which does not seem to have been previously reported in the literature. Results of these studies may help in choosing the optimum detector for given experimental conditions.

  5. Methodology for DSC calibration in high heating rates

    Directory of Open Access Journals (Sweden)

    Carlos Isidoro Braga

    2011-05-01

    Full Text Available Despite the large use of differential scanning calorimetry (DSC technique in advanced polymer materials characterization, the new methodology called DSC in high heating rates was developed. The heating rate during conventional DSC experiments varying from 10 to 20ºC.min-¹, sample mass from 10 to 15mg and standard aluminum sample pan weighting, approximately, 27mg. In order to contribute to a better comprehension of DSC behavior in different heating rates, this work correlates as high heating rate influences to the thermal events in DSC experiments. Samples of metallic standard (In, Pb, Sn and Zn with masses varying from 0.570mg to 20.9mg were analyzed in multiples sample heating rate from 4 to 324°C. min-¹. In order to make properly all those experiments, a precise and careful temperature and enthalpy calibrations were performed and deeply discussed. Thus, this work shows a DSC methodology able to generate good and reliable results on experiments under any researcher choice heating rates to characterize the advanced materials used, for example, for aerospace industry. Also it helps the DSC users to find in their available instruments, already installed, a better and more accurate DSC test results, improving in just one shot the analysis sensitivity and resolution. Polypropylene melting and enthalpy thermal events are also studied using both the conventional DSC method and high heating rate method.

  6. Efficient, high rep rate, large-bore kinetically enhanced copper vapor laser with low (thermal assembly.

    Science.gov (United States)

    Singh, Bijendra; Subramaniam, V V; Daultabad, S R; Chakraborty, Ashim

    2009-10-01

    Large-bore kinetically enhanced copper vapor laser (CVL) based on new thermal assembly consisting of different density zones of insulation material (alumina fiber) around the discharge tube is demonstrated for the first time with efficiency eta > or = 1% at extremely low specific input power (SIP) of insulation material, efficiency of approximately 1.2% was achieved at lowest SIP of approximately 0.75 kW/l. Net reduction in the input power of approximately 1 kW was observed on using this thermal assembly as compared to nonprofiled thermal assembly. These results show significant improvement (25%-30%) at low input requirements of the laser on using new thermal assembly around the discharge tube with overall electro-optical efficiency eta > or = 1%. Maximum laser power achieved from the laser was approximately 78 W at approximately 9.8 kHz rep rate with efficiency of approximately 1.4%. This large-bore CVL is also capable of operating efficiently (eta approximately 1%) at high rep rate of -17 kHz with maximum laser power of approximately 50 W. Performance of the laser under various operating conditions is also presented in this short paper.

  7. Evolution of high tooth replacement rates in sauropod dinosaurs.

    Directory of Open Access Journals (Sweden)

    Michael D D'Emic

    Full Text Available BACKGROUND: Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. METHODOLOGY/PRINCIPAL FINDINGS: We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days. Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. CONCLUSIONS/SIGNIFICANCE: Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size, and derived titanosaurs and

  8. Evolution of high tooth replacement rates in sauropod dinosaurs.

    Science.gov (United States)

    D'Emic, Michael D; Whitlock, John A; Smith, Kathlyn M; Fisher, Daniel C; Wilson, Jeffrey A

    2013-01-01

    Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days). Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size), and derived titanosaurs and diplodocoids independently evolved the highest known tooth replacement rates among archosaurs.

  9. Integrating GPS with GLONASS for high-rate seismogeodesy

    Science.gov (United States)

    Geng, Jianghui; Jiang, Peng; Liu, Jingnan

    2017-04-01

    High-rate GPS is a precious seismogeodetic tool to capture coseismic displacements unambiguously and usually improved by sidereal filtering to mitigate multipath effects dominating the periods of tens of seconds to minutes. We further introduced GLONASS (Globalnaya navigatsionnaya sputnikovaya sistema) data into high-rate GPS to deliver over 2000 24 h displacements at 99 stations in Europe. We find that the major displacement errors induced by orbits and atmosphere on the low-frequency band that are not characterized by sidereal repeatabilities can be amplified markedly by up to 40% after GPS sidereal filtering. In contrast, integration with GLONASS can reduce the noise of high-rate GPS significantly and near uniformly over the entire frequency band, especially for the north components by up to 40%, suggesting that this integration is able to mitigate more errors than only multipath within high-rate GPS. Integrating GPS with GLONASS outperforms GPS sidereal filtering substantially in ameliorating displacement noise by up to 60% over a wide frequency band (e.g., 2 s-0.5 days) except a minor portion between 100 and 1000 s. High-rate multi-GNSS (Global Navigation Satellite System) can be enhanced further by sidereal filtering, which should however be carefully implemented to avoid adverse complications of the noise spectrum of displacements.

  10. A new strategy to improve the high-rate performance of hydrogen storage alloys with MoS2 nanosheets

    Science.gov (United States)

    Chen, L. X.; Zhu, Y. F.; Yang, C. C.; Chen, Z. W.; Zhang, D. M.; Jiang, Q.

    2016-11-01

    The poor high-rate dischargeability of negative electrode materials (hydrogen storage alloys) has hindered applications of nickel metal hydride batteries in high-power fields, new-energy vehicles, power tools, military devices, etc. In this work, a new strategy is developed to improve the high-rate performance of hydrogen storage alloys by coating MoS2 nanosheets on alloy surfaces. The capacity retention rate of the composite electrode reaches 50.5% at a discharge current density of 3000 mA g-1, which is 2.7 times that of bare alloy (18.4%). The density functional theory simulations indicate that such an outstanding performance is derived from adjustments of ion concentrations at the electrode/electrolyte interface by MoS2 nanosheets: (1) the higher OH- concentration facilitates the electrochemical reaction of MHads + OH- - e- → M + H2O; and (2) the lower H+ concentration leads to a large gradient between the electrode/electrolyte interface and interior of alloys, which is beneficial for the diffusion of atomic hydrogen during the discharging process.

  11. Digitized reality: Effects of high frame rate on visual perception

    OpenAIRE

    Loertscher, Miriam Laura; Iseli, Christian

    2016-01-01

    The digital revolution changed film production and its aesthetics in many ways. Although motion is a defining feature of moving images, it is also one of their most problematic aspects because of blurred images or other signal processing artifacts. An artistic research project was conducted to test the effects of high frame rates (HFR) on visual perception. Typical camera movements were recorded in different frame rates (24 / 48 / 96 fps) to generate test sequences for a cinema experiment. 69...

  12. Charge and Discharge Analyses of a PCM Storage System Integrated in a High-Temperature Solar Receiver

    Directory of Open Access Journals (Sweden)

    Ambra Giovannelli

    2017-11-01

    Full Text Available Solar Dish Micro Gas Turbine (MGT systems have the potential to become interesting small-scale power plants in off-grid or mini-grid contexts for electricity or poly-generation production. The main challenging component of such systems is the solar receiver which should operate at high temperatures with concentrated solar radiations, which strongly vary with time. This paper deals with the design and the analysis of a novel solar receiver integrated with a short-term storage system based on Phase Change Materials to prevent sudden variations in the maximum temperature of the MGT working fluid. Particularly, the charge and discharge behavior of the storage system was analyzed by means of Computational Fluid Dynamic methods to evaluate the potentiality of the concept and the component capabilities. Achieved results were highly satisfactory: the novel solar receiver has a good thermal inertia and can prevent relevant fluctuations in the working fluid temperature for 20–30 min.

  13. Relationship between insurance and 30-day readmission rates in patients 65 years and older discharged from an acute care hospital with hospice services.

    Science.gov (United States)

    Whitney, Patricia; Chuang, Elizabeth J

    2016-10-01

    Patients who are dual eligible for both Medicare and Medicaid have previously been shown to have increased healthcare utilization and cost. However, this relationship has not been examined for patients at the end of life. Dual eligible patients enrolled in hospice may receive more comprehensive care in the community, reducing readmissions in the final weeks or months of life. Determine whether patients who have dual coverage with Medicare and Medicaid and are discharged with referral to hospice services after palliative care consult during their hospitalization differ in their 30-day readmission rate compared with similar patients with other types of insurance. Retrospective cohort study. Three acute care hospitals affiliated with Montefiore Medical Center in the Bronx, New York. In total, 2755 inpatients who received palliative care consultation and were discharged with hospice services. Dual eligible for Medicare and Medicaid compared with other insurance status. Readmission to Montefiore Medical Center for any reason within 30 days of the index admission. Overall, 9.24% of patients with dual Medicare and Medicaid coverage were readmitted within 30 days compared with 13.12% of others (adjusted odds ratio: 0.77; 95% confidence interval: 0.59-0.98; P = 0.041). Dual eligibility for Medicare and Medicaid is associated with lower 30-day readmission rates in patients enrolled in a hospice program. Insurance coverage that increases access to custodial care (home attendant hours and residential care) may help decrease burdensome hospital readmissions near the end of life. Journal of Hospital Medicine 2016;11:688-693. © 2016 Society of Hospital Medicine. © 2016 Society of Hospital Medicine.

  14. A review of reaction rates in high temperature air

    Science.gov (United States)

    Park, Chul

    1989-01-01

    The existing experimental data on the rate coefficients for the chemical reactions in nonequilibrium high temperature air are reviewed and collated, and a selected set of such values is recommended for use in hypersonic flow calculations. For the reactions of neutral species, the recommended values are chosen from the experimental data that existed mostly prior to 1970, and are slightly different from those used previously. For the reactions involving ions, the recommended rate coefficients are newly chosen from the experimental data obtained more recently. The reacting environment is assumed to lack thermal equilibrium, and the rate coefficients are expressed as a function of the controlling temperature, incorporating the recent multitemperature reaction concept.

  15. THE AMERICAN HIGH SCHOOL GRADUATION RATE: TRENDS AND LEVELS*

    Science.gov (United States)

    Heckman, James J.; LaFontaine, Paul A.

    2009-01-01

    This paper applies a unified methodology to multiple data sets to estimate both the levels and trends in U.S. high school graduation rates. We establish that (a) the true rate is substantially lower than widely used measures; (b) it peaked in the early 1970s; (c) majority/minority differentials are substantial and have not converged for 35 years; (d) lower post-1970 rates are not solely due to increasing immigrant and minority populations; (e) our findings explain part of the slowdown in college attendance and rising college wage premiums; and (f) widening graduation differentials by gender help explain increasing male-female college attendance gaps. PMID:20625528

  16. High rate tests of the LHCb RICH Upgrade system

    CERN Multimedia

    Blago, Michele Piero

    2016-01-01

    One of the biggest challenges for the upgrade of the LHCb RICH detectors from 2020 is to readout the photon detectors at the full 40 MHz rate of the LHC proton-proton collisions. A test facility has been setup at CERN with the purpose to investigate the behaviour of the Multi Anode PMTs, which have been proposed for the upgrade, and their readout electronics at high trigger rates. The MaPMTs are illuminated with a monochromatic laser that can be triggered independently of the readout electronics. A first series of tests, including threshold scans, is performed at low trigger rates (20 kHz) for both the readout and the laser with the purpose to characterise the behaviour of the system under test. Then the trigger rate is increased in two separate steps. First the MaPMTs are exposed to high illumination by triggering the pulsed laser at a high (20 MHz) repetition rate while the DAQ is readout at the same low rate as before. In this way the performance of the MaPMTs and the attached electronics can be evaluated ...

  17. High strain rate superplasticity in metals and composites

    Energy Technology Data Exchange (ETDEWEB)

    Nieh, T.G.; Wadsworth, J. [Lawrence Livermore National Lab., CA (United States); Higashi, K. [Osaka Prefecture Univ., Sakai (Japan). Dept. of Mechanicl Systems Engineering

    1993-07-01

    Superplastic behavior at very high strain rates (at or above 1 s{sup {minus}1}) in metallic-based materials is an area of increasing interest. The phenomenon has been observed quite extensively in metal alloys, metal-matrix composites (MMC), and mechanically-alloyed (MA) materials. In the present paper, experimental results on high strain rate behavior in 2124 Al-based materials, including Zr-modified 2124, SiC-reinforced 2124, MA 2124, and MA 2124 MMC, are presented. Except for the required fine grain size, details of the structural requirements of this phenomenon are not yet understood. Despite this, a systematic approach to produce high strain rate superplasticity (HSRS) in metallic materials is given in this paper. Evidences indicate that the presence of a liquid phase, or a low melting point region, at boundary interfaces is responsible for HSRS.

  18. Complex pulsing schemes for high frame rate imaging

    DEFF Research Database (Denmark)

    Misaridis, Thanassis; Fink, Mathias; Jensen, Jørgen Arendt

    2002-01-01

    High frame rate ultrasound imaging can be achieved by simultaneous transmission of multiple focused beams along different directions. However, image quality degrades by the interference among beams. An alternative approach is to transmit spherical waves of a basic short pulse with frequency codin......B. With the proposed imaging strategy of pulse train excitation, a whole image can be formed with only two emissions, making it possible to obtain high quality images at a frame rate of 20 to 25 times higher than that of conventional phased array imaging......High frame rate ultrasound imaging can be achieved by simultaneous transmission of multiple focused beams along different directions. However, image quality degrades by the interference among beams. An alternative approach is to transmit spherical waves of a basic short pulse with frequency coding...

  19. Semi-solid electrodes having high rate capability

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Yet-Ming; Duduta, Mihai; Holman, Richard; Limthongkul, Pimpa; Tan, Taison

    2017-11-28

    Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode, a semi-solid cathode that includes a suspension of an active material and a conductive material in a liquid electrolyte, and an ion permeable membrane disposed between the anode and the cathode. The semi-solid cathode has a thickness in the range of about 250 .mu.m-2,500 .mu.m, and the electrochemical cell has an area specific capacity of at least 5 mAh/cm.sup.2 at a C-rate of C/2.

  20. Discharge coefficient of semi-circular labyrinth side weir in ...

    African Journals Online (AJOL)

    Labyrinth weirs have a proven hydraulic advantage due to their increased discharge rate at the same head for a given design condition. ... coefficient of the semi-circular labyrinth side weir gives a relatively high discharge coefficient value compared to other types of classic side weir positioned on a straight channel.

  1. Laser-induced incandescence (LII) diagnostic for in situ monitoring of nanoparticle synthesis in a high-pressure arc discharge

    Science.gov (United States)

    Yatom, Shurik; Vekselman, Vladislav; Mitrani, James; Stratton, Brentley; Raitses, Yevgeny; LaboratoryPlasma Nanosynthesis Team

    2016-10-01

    A DC arc discharge is commonly used for synthesis of carbon nanoparticles, including buckyballs, carbon nanotubes, and graphene flakes. In this work we show the first results of nanoparticles monitored during the arc discharge. The graphite electrode is vaporized by high current (60 A) in a buffer Helium gas leading to nanoparticle synthesis in a low temperature plasma. The arc was shown to oscillate, which can possibly influence the nano-synthesis. To visualize the nanoparticles in-situ we employ the LII technique. The nanoparticles with radii >50 nm, emerging from the arc area are heated with a short laser pulse and incandesce. The resulting radiation is captured with an ICCD camera, showing the location of the generated nanoparticles. The images of incandescence are studied together with temporally synchronized fast-framing imaging of C2 emission, to connect the dynamics of arc instabilities, C2 molecules concentration and nanoparticles. The time-resolved incandescence signal is analyzed with combination of ex-situ measurements of the synthesized nanoparticles and LII modeling, to provide the size distribution of produced nanoparticles. This work was supported by US Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division.

  2. Exploring X-ray lasing in nitrogen pinch plasma at very high and fast discharge current excitation

    Science.gov (United States)

    Barnwal, S.; Nigam, S.; Aneesh, K.; Prasad, Y. B. S. R.; Sharma, M. L.; Tripathi, P. K.; Joshi, A. S.; Naik, P. A.; Vora, H. S.; Gupta, P. D.

    2017-06-01

    The possibility to demonstrate X-ray lasing in nitrogen at 13.4 nm through recombination scheme driven by capillary discharge excitation has been explored at a high discharge current of 95 kA, with 46 ns quarter period. The emission from nitrogen pinch plasma showed a fast pulse at the instant of pinch formation, overriding the long duration Bremsstrahlung emission. The spectroscopic study revealed dominant X-ray line emissions at 2.8 and 2.1 nm, apart from various X-ray line emissions at higher wavelengths. Line emission at 2.8 nm confirms the formation of NVI charge state of nitrogen. At lower pressures, faint emission of Ly-α line at 2.4 nm indicated formation of NVII ions by further heating. The favourable role of pre-pulse in the formation of higher charge states of nitrogen was also established beyond doubt. This study provides important inputs for future experiments towards demonstration of X-ray lasing at 13.4 nm.

  3. High removal rate laser-based coating removal system

    Science.gov (United States)

    Matthews, Dennis L.; Celliers, Peter M.; Hackel, Lloyd; Da Silva, Luiz B.; Dane, C. Brent; Mrowka, Stanley

    1999-11-16

    A compact laser system that removes surface coatings (such as paint, dirt, etc.) at a removal rate as high as 1000 ft.sup.2 /hr or more without damaging the surface. A high repetition rate laser with multiple amplification passes propagating through at least one optical amplifier is used, along with a delivery system consisting of a telescoping and articulating tube which also contains an evacuation system for simultaneously sweeping up the debris produced in the process. The amplified beam can be converted to an output beam by passively switching the polarization of at least one amplified beam. The system also has a personal safety system which protects against accidental exposures.

  4. On transition from diffuse mode to the constricted one with high-current cathode spot in overvoltage open discharge in D2

    Science.gov (United States)

    Akishev, Yu S.; Karalnik, V. B.; Medvedev, M. A.; Petryakov, A. V.; Trushkin, N. I.; Shafikov, A. G.

    2017-11-01

    So called “open discharges” in a narrow gap between the solid cathode and grid anode are widely used for generation of the pulsed high-current electron beams with energy up to 100 keV. The need to get high-energy e-beams leads to the necessity in using of strong overvoltage of the short gas gap with the reduced electric field of the order of 105 Td or higher. The discharge under strong overvoltage is unstable and tends to transit into high-current regime with low voltage. In the case of the open discharge in D2 at low pressure (about 0.5-2 Torr) and powered by stepwise voltage with amplitude up to 25 kV we revealed that this discharge exhibits two diffuse regimes which follow one by one and finally transits into the constricted mode with formation of high-current spots on the cathode. The physical properties of these gas discharge regimes have been explored in detail with the usage of the fast multi-frame camera synchronized with the current and voltage of discharge. Our findings promote more insight into physics of the overvoltage open discharge generating the e-beams with energy up to 25 keV.

  5. Derivation and test of high order fluid model for streamer discharges

    NARCIS (Netherlands)

    A. Markosyan (Aram); S. Dujko (Sasa); U. Ebert (Ute); A. Blaszczyk; R. Hiptmair; P. Leuchtmann; J. Ostrowski

    2012-01-01

    textabstractA high order fluid model for streamer dynamics is developed by closing the system after the 4th moment of the Boltzmann equation in local mean energy approximation. This is done by approximating the high order pressure tensor in the heat flux equation through the previous moments.

  6. Study of the thermohydraulics of CO2 discharge from a high pressure reservoir

    NARCIS (Netherlands)

    Ahmad, M.; Osch, M.B.V.; Buit, L.; Florisson, O.; Hulsbosch-Dam, C.; Spruijt, M.; Davolio, F.

    2013-01-01

    An experimental test set up has been constructed to carry out controlled CO2 release experiments from a high pressure vessel. The test set up is made up of a 500l stainless steel vessel where CO2 can be introduced up to high pressures and where controlled releases can be conducted. The work

  7. Sensitivity to Envelope Interaural Time Differences at High Modulation Rates

    Science.gov (United States)

    Bleeck, Stefan; McAlpine, David

    2015-01-01

    Sensitivity to interaural time differences (ITDs) conveyed in the temporal fine structure of low-frequency tones and the modulated envelopes of high-frequency sounds are considered comparable, particularly for envelopes shaped to transmit similar fidelity of temporal information normally present for low-frequency sounds. Nevertheless, discrimination performance for envelope modulation rates above a few hundred Hertz is reported to be poor—to the point of discrimination thresholds being unattainable—compared with the much higher (>1,000 Hz) limit for low-frequency ITD sensitivity, suggesting the presence of a low-pass filter in the envelope domain. Further, performance for identical modulation rates appears to decline with increasing carrier frequency, supporting the view that the low-pass characteristics observed for envelope ITD processing is carrier-frequency dependent. Here, we assessed listeners’ sensitivity to ITDs conveyed in pure tones and in the modulated envelopes of high-frequency tones. ITD discrimination for the modulated high-frequency tones was measured as a function of both modulation rate and carrier frequency. Some well-trained listeners appear able to discriminate ITDs extremely well, even at modulation rates well beyond 500 Hz, for 4-kHz carriers. For one listener, thresholds were even obtained for a modulation rate of 800 Hz. The highest modulation rate for which thresholds could be obtained declined with increasing carrier frequency for all listeners. At 10 kHz, the highest modulation rate at which thresholds could be obtained was 600 Hz. The upper limit of sensitivity to ITDs conveyed in the envelope of high-frequency modulated sounds appears to be higher than previously considered. PMID:26721926

  8. Compressed sensing for high frame rate, high resolution and high contrast ultrasound imaging.

    Science.gov (United States)

    Jing Liu; Qiong He; Jianwen Luo

    2015-08-01

    Compressed sensing (CS) or compressive sampling allows much lower sampling frequency than the Nyquist sampling frequency. In this paper, we propose a novel technique, named compressed sensing based synthetic transmit aperture (CS-STA), to speed up the acquisition of ultrasound imaging. Ultrasound transducer transmits plane wave with random apodizations for several times and receives the corresponding echoes. The full dataset of STA is then recovered from the recorded echoes using a CS reconstruction algorithm. Finally, a standard STA beamforming is performed on the dataset to form a B-mode image. When the number of CS-STA firings is smaller than the number of STA firings, higher frame rate is achieved. In addition, CS-STA maintains the high resolution of STA because of the CS recovered full dataset of STA, and improves the contrast due to plane wave firings. Computer simulations and phantom experiments are carried out to investigate the feasibility and performance of the proposed CS-STA method. The CS-STA method is proven to be capable of obtaining simultaneously high frame rate, high solution and high contrast ultrasound imaging.

  9. GPU accelerated OCT processing at megahertz axial scan rate and high resolution video rate volumetric rendering

    Science.gov (United States)

    Jian, Yifan; Wong, Kevin; Sarunic, Marinko V.

    2013-03-01

    In this report, we describe how to highly optimize a CUDA based platform to perform real time optical coherence tomography data processing and 3D volumetric rendering using commercially-available cost-effective graphic processing units (GPUs). The maximum complete attainable axial scan processing rate (including memory transfer and rendering frame) was 2.2 megahertz for 16 bits pixel depth and 2048 pixels/A-scan, the maximum 3D volumetric rendering speed is 23 volumes/second (size:1024×256×200). To the best of our knowledge, this is the fastest processing rate reported to date with single-chip GPU and the first implementation of real time video rate volumetric OCT processing and rendering that is capable of matching the ultrahigh-speed OCT acquisition rates.

  10. 21 CFR 1040.30 - High-intensity mercury vapor discharge lamps.

    Science.gov (United States)

    2010-04-01

    ... operating time means the sum of the times during which electric current passes through the high-pressure arc... the Director, Center for Devices and Radiological Health, with the key to the code or symbols and the...

  11. A Zero Dimensional Time-Dependent Model of High-Pressure Ablative Capillary Discharge (Preprint)

    National Research Council Canada - National Science Library

    Pekker, Leonid

    2008-01-01

    ... plasma core and the ablative capillary walls. The model includes the thermodynamics of partially ionized plasmas and non-ideal effects taking place in the high density plasma and assumes local thermodynamic equilibrium (LTE...

  12. Low primary cesarean rate and high VBAC rate with good outcomes in an Amish birthing center.

    Science.gov (United States)

    Deline, James; Varnes-Epstein, Lisa; Dresang, Lee T; Gideonsen, Mark; Lynch, Laura; Frey, John J

    2012-01-01

    Recent national guidelines encourage a trial of labor after cesarean (TOLAC) as a means of increasing vaginal births after cesarean (VBACs) and decreasing the high US cesarean birth rate and its consequences (2010 National Institute of Health Consensus Statement and American College of Obstetricians and Gynecologists revised guideline). A birthing center serving Amish women in Southwestern Wisconsin offered an opportunity to look at the effects of local culture and practices that support vaginal birth and TOLAC. This study describes childbirth and perinatal outcomes during a 17-year period in LaFarge, Wisconsin. We undertook a retrospective analysis of the records of all women admitted to the birth center in labor. Main outcome measures include rates of cesarean deliveries, TOLAC and VBAC deliveries, and perinatal outcomes for 927 deliveries between 1993 and 2010. The cesarean rate was 4% (35 of 927), the TOLAC rate was 100%, and the VBAC rate was 95% (88 of 92). There were no cases of uterine rupture and no maternal deaths. The neonatal death rate of 5.4 of 1,000 was comparable to that of Wisconsin (4.6 of 1,000) and the United States (4.5 of 1,000). Both the culture of the population served and a number of factors relating to the management of labor at the birthing center have affected the rates of cesarean delivery and TOLAC. The results of the LaFarge Amish study support a low-technology approach to delivery where good outcomes are achieved with low cesarean and high VBAC rates.

  13. Electrophoretic Deposition of Gallium with High Deposition Rate

    Directory of Open Access Journals (Sweden)

    Hanfei Zhang

    2014-12-01

    Full Text Available In this work, electrophoretic deposition (EPD is reported to form gallium thin film with high deposition rate and low cost while avoiding the highly toxic chemicals typically used in electroplating. A maximum deposition rate of ~0.6 μm/min, almost one order of magnitude higher than the typical value reported for electroplating, is obtained when employing a set of proper deposition parameters. The thickness of the film is shown to increase with deposition time when sequential deposition is employed. The concentration of Mg(NO32, the charging salt, is also found to be a critical factor to control the deposition rate. Various gallium micropatterns are obtained by masking the substrate during the process, demonstrating process compatibility with microfabrication. The reported novel approach can potentially be employed in a broad range of applications with Ga as a raw material, including microelectronics, photovoltaic cells, and flexible liquid metal microelectrodes.

  14. High ratings of satisfaction with fertility treatment are common

    DEFF Research Database (Denmark)

    Schmidt, L; Holstein, B E; Boivin, J

    2003-01-01

    /delivery and the report of marital benefits resulting from the infertility experience. Lower social class was a significant predictor for satisfaction. CONCLUSIONS: Both men and women in fertility treatment had high ratings on medical and patient-centred care. It seemed that satisfaction with the psychosocial services...

  15. Advances in high rate anaerobic treatment: staging of reactor systems.

    NARCIS (Netherlands)

    Lier, van J.B.; Zee, van der F.P.; Tan, N.C.G.; Rebac, S.; Kleerebezem, R.

    2001-01-01

    Anaerobic wastewater treatment (AnWT) is considered as the most cost-effective solution for organically polluted industrial waste streams. Particularly the development of high-rate systems, in which hydraulic retention times are uncoupled from solids retention times, has led to a world-wide

  16. High rate of teenage pregnancy and sexually transmitted infections ...

    African Journals Online (AJOL)

    There is increased in teenage pregnancy despite the presence of dual protection practice and health care awareness programmes related to health and sexuality education in South Africa. The present study explores the underlying causes of high teenage pregnancy and sexually transmitted diseases rates, including HIV ...

  17. High Frame Rate Synthetic Aperture 3D Vector Flow Imaging

    DEFF Research Database (Denmark)

    Villagómez Hoyos, Carlos Armando; Holbek, Simon; Stuart, Matthias Bo

    2016-01-01

    , current volumetric ultrasonic flow methods are limited to one velocity component or restricted to a reduced field of view (FOV), e.g. fixed imaging planes, in exchange for higher temporal resolutions. To solve these problems, a previously proposed accurate 2-D high frame rate vector flow imaging (VFI...

  18. Minimum Variance Beamforming for High Frame-Rate Ultrasound Imaging

    DEFF Research Database (Denmark)

    Holfort, Iben Kraglund; Gran, Fredrik; Jensen, Jørgen Arendt

    2007-01-01

    emissions. An increase in resolution is seen when using only one single emission. Furthermore, it is seen that an increase of the number of emissions does not alter the FWHM. Thus, the MV beamformer introduces the possibility for high frame-rate imaging with increased resolution....

  19. Behaviour of uranium alloys at high loading rates

    Energy Technology Data Exchange (ETDEWEB)

    Rolc, S.; Pechacek, J.; Krejci, J. (Ceskoslovenska Akademie Ved, Brno (CS). Ustav Fyzikalni Metalurgie); Buchar, J.

    1991-10-01

    The mechanical behaviour of depleted uranium, uranium with molybdenum, niobium, titanium and rhenium was investigated under high strain rates. The Hopkinson split pressure bar was used. The spallation of these materials was also studied. The correlation of the spall strength, {sigma}{sub c}, with flow properties was found. 11 refs., 4 figs., 1 tab..

  20. High rates of catalytic hydrogen combustion with air over coated ...

    Indian Academy of Sciences (India)

    BHASKAR DEVU MUKRI

    2017-08-02

    Aug 2, 2017 ... High rates of catalytic hydrogen combustion with air over. Ti0.97Pd0.03O2−δ coated cordierite monolith. BHASKAR DEVU MUKRI. ∗ and M S HEGDE. Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India. E-mail: bhaskardm@gmail.com. MS received 9 May 2017; ...

  1. Temporal dynamics of high repetition rate pulsed single longitudinal ...

    Indian Academy of Sciences (India)

    Theoretical and experimental studies of temporal dynamics of grazing incidence grating (GIG) cavity, single-mode dye laser pumped by high repetition rate copper vapour laser (CVL) are presented. Spectral chirp of the dye laser as they evolve in the cavity due to transient phase dynamics of the amplifier gain medium is ...

  2. Adapting high-rate anaerobic treatment to Middle East conditions

    NARCIS (Netherlands)

    Mahmoud, N.A.; Zeeman, G.; Lier, van J.B.

    2008-01-01

    High-rate anaerobic technologies offer cost-effective solutions for sewage treatment in the Middle East and Palestine in particular. The sewage characteristics in Palestine are quite different from the values elsewhere and show solids contents of more than 1000 mg chemical oxygen demand (COD)ss/L

  3. Plant respirometer enables high resolution of oxygen consumption rates

    Science.gov (United States)

    Foster, D. L.

    1966-01-01

    Plant respirometer permits high resolution of relatively small changes in the rate of oxygen consumed by plant organisms undergoing oxidative metabolism in a nonphotosynthetic state. The two stage supply and monitoring system operates by a differential pressure transducer and provides a calibrated output by digital or analog signals.

  4. Methanol conversion in high-rate anaerobic reactors

    NARCIS (Netherlands)

    Weijma, J.; Stams, A.J.M.

    2001-01-01

    An overview on methanol conversion in high-rate anaerobic reactors is presented, with the focus on technological as well as microbiological aspects. The simple C1-compound methanol can be degraded anaerobically in a complex way, in which methanogens, sulfate reducing bacteria and homoacetogens

  5. Twinning in copper deformed at high strain rates

    Indian Academy of Sciences (India)

    †Department of Physics, Nelson Mandela Metropolitan University, Port Elizabeth, South Africa. MS received 25 February 2010; revised 13 August 2012. Abstract. Copper samples having varying microstructures were deformed at high strain rates using a split-. Hopkinson pressure bar. Transmission electron microscopy ...

  6. Facile synthesis of Co3O4 spheres and their unexpected high specific discharge capacity for Lithium-ion batteries

    Science.gov (United States)

    Wang, Zhengdong; Qu, Shaohua; Cheng, Yonghong; Zheng, Chenghui; Chen, Siyu; Wu, Hongjing

    2017-09-01

    We report a facile, one-pot hydrothermal synthesis of Co3O4 solid spheres and multi-shelled Co3O4 hollow spheres with a controlled number of movable internal Co3O4 shells. Moreover, the magnetic properties of the multi-shelled Co3O4 hollow spheres were first investigated by the SQUID magnetometer. Interestingly, the Co3O4 solid spheres calcined at 430 °C deliver an unexpected high specific discharge capacity of 1976 and 1129 mAh g-1 for the 17th and 100th cycle at 100 mA g-1, respectively. In addition, the Co3O4 solid spheres calcined at 430 °C also show good capacity retention (i.e., 1129 mAh g-1 after 100 cycles). The significant performance improvement offers the potential to open up an avenue for next-generation LIBs.

  7. Multitudinous industrialized fabrication of BNNT with high-energy ball milling and arc-discharge-aided template methods

    Science.gov (United States)

    Wang, Shouren; Wen, Daosheng; Wang, Gaoqi; Yang, Liying; Guo, Peiquan; Qiao, Yang

    2017-10-01

    A novel large-scale fabrication technology for single-walled boron nitride nanotube (BNNT) relying on a template of single-walled carbon nanotube (SWCNTs) was introduced. In order to obtain large-scale product, the high-energy ball milling-aided heating technology was used to promote the formation of BNNTs. And arc-discharge methods were used to provide nitrogen ion source. The products were oxidized at 800 °C in air atmosphere to obtain pure BNNTs. The structure and morphology of BNNTs were characterized by X-ray diffraction, transmission electron microscopy, Fourier transformation infrared spectroscopy, and thermogravimetric analysis. The multitudinous industrialized preparation methods for BNNTs were realized as a simple and effective route.

  8. Towards long pulse high performance discharges in Tore Supra: experimental knowledge and technological developments for heat exhaust

    Energy Technology Data Exchange (ETDEWEB)

    TORE SUPRA Collaboration

    1995-08-01

    This document deals with fusion heat exhaust experiments in Tore Supra tokamak. The purpose of the Tore Supra tokamak is to achieve and control long pulse powerful discharges. High input power is required to generate the non inductive current, approximately 25 MW . The conception and realisation of a Plasma Facing Component (PFC) scheme able to deal with this large amount of power is the main issue. A description of the water loop used for power removal and of the calorimetric system to determine the overall heat exhaust balance is provided. The infra-red measurements used during plasma operation are also described, together with several heat exhaust devices. The behaviour of ion cyclotron and lower hybrid wave launchers is addressed. Eventually, some information is provided on technological developments of PFC in Tore Supra. (TEC). 61 refs., 34 figs.

  9. Discharge lamp technologies

    Science.gov (United States)

    Dakin, James

    1994-03-01

    This talk is an overview of discharge lamp technology commonly employed in general lighting, with emphasis on issues pertinent to lighting for plant growth. Since the audience is primarily from the plant growth community, and this begins the light source part of the program, we will start with a brief description of the discharge lamps. Challenges of economics and of thermal management make lamp efficiency a prime concern in controlled environment agriculture, so we will emphasize science considerations relating to discharge lamp efficiency. We will then look at the spectra and ratings of some representative lighting products, and conclude with a discussion of technological advances.

  10. Discharge lamp technologies

    Science.gov (United States)

    Dakin, James

    1994-01-01

    This talk is an overview of discharge lamp technology commonly employed in general lighting, with emphasis on issues pertinent to lighting for plant growth. Since the audience is primarily from the plant growth community, and this begins the light source part of the program, we will start with a brief description of the discharge lamps. Challenges of economics and of thermal management make lamp efficiency a prime concern in controlled environment agriculture, so we will emphasize science considerations relating to discharge lamp efficiency. We will then look at the spectra and ratings of some representative lighting products, and conclude with a discussion of technological advances.

  11. INTENSE ENERGETIC GAS DISCHARGE

    Science.gov (United States)

    Luce, J.S.

    1960-03-01

    A method and apparatus for initiating and sustaining an energetic gas arc discharge are described. A hollow cathode and a hollow anode are provided. By regulating the rate of gas flow into the interior of the cathode, the arc discharge is caused to run from the inner surface of the cathode with the result that adequate space-charge neutralization is provided inside the cathode but not in the main arc volume. Thus, the gas fed to the cathode is substantially completely ionized before it leaves the cathode, with the result that an energetic arc discharge can be maintained at lower operating pressures.

  12. High salmon density and low discharge create periodic hypoxia in coastal rivers

    Science.gov (United States)

    Christopher J. Sergeant; J. Ryan Bellmore; Casey McConnell; Jonathan W. Moore

    2017-01-01

    Dissolved oxygen (DO) is essential to the survival of almost all aquatic organisms. Here, we examine the possibility that abundant Pacific salmon (Oncorhynchus spp.) and low streamflow combine to create hypoxic events in coastal rivers. Using high-frequency DO time series from two similar watersheds in southeastern Alaska, we summarize DO regimes...

  13. Discharge Characteristics of Large-Area High-Power RF Ion Source for Positive and Negative Neutral Beam Injectors

    Science.gov (United States)

    Chang, Doo-Hee; Jeong, Seung Ho; Park, Min; Kim, Tae-Seong; Jung, Bong-Ki; Lee, Kwang Won; In, Sang Ryul

    2016-12-01

    A large-area high-power radio-frequency (RF) driven ion source was developed for positive and negative neutral beam injectors at the Korea Atomic Energy Research Institute (KAERI). The RF ion source consists of a driver region, including a helical antenna and a discharge chamber, and an expansion region. RF power can be transferred at up to 10 kW with a fixed frequency of 2 MHz through an optimized RF matching system. An actively water-cooled Faraday shield is located inside the driver region of the ion source for the stable and steady-state operations of high-power RF discharge. Plasma ignition of the ion source is initiated by the injection of argon-gas without a starter-filament heating, and the argon-gas is then slowly exchanged by the injection of hydrogen-gas to produce pure hydrogen plasmas. The uniformities of the plasma parameter, such as a plasma density and an electron temperature, are measured at the lowest area of the driver region using two RF-compensated electrostatic probes along the direction of the short-and long-dimensions of the driver region. The plasma parameters will be compared with those obtained at the lowest area of the expansion bucket to analyze the plasma expansion properties from the driver region to the expansion region. supported by the Ministry of Science, ICT and Future Planning of the Republic of Korea under the ITER Technology R&D Program, and National R&D Program Through the National Research Foundation of Korea (NRF) Funded by the Ministry of Science, ICT & Future Planning (NRF-2014M1A7A1A03045372)

  14. The main natural lows of high-rate coal pyrolysis

    Directory of Open Access Journals (Sweden)

    Chemyavsky Nikola V.

    2003-01-01

    Full Text Available The importance of coal pyrolysis studies for the development of energy technologies is evident, since pvrolysis is the first stage of any process of coal thermal conversion. In combustion, pyrolysis determines conditions of coal ignition and the rate of char after-burning, in gasification, pyrolysis determines total yield of gasification products. It must be noted that in modern energy technologies pyrolysis occurs at high late of coal particle heating (=10 K/s for different fluidized bed, or FB-technologies or super-high-rate (>10**5 K/s for entrained-flow gasification, and in some of them at high pressure. In CETI during last 12 years the detailed study of pyrolysis in FB laboratory-scale PYROLYSIS-D plant and entramed-flow pilot-scale GSP-01 plant, was carried out. In this paper main results of mentioned investigations are given. Kinetic constants for bituminous coals and anthracite high heating rates in entrained flow for high temperatures (>1500 °C and >1900 °C, and in fluidized bed conditions in temperature range 972-1273 K. In order to describe data obtained in fluidized bed conditions, G--model based method of calculation of devolatization dynamics was suited to FB heating conditions. Calculated and experimental kinetic data are in good agreement. The result proves that at FB-pvrolysis conditions intrinsic mass-transfer limitations are negligible and devolatilization is really kinetic-controlled.

  15. Impact of receiver and constellation on high rate GNSS phase rate measurements to monitor ionospheric irregularities

    Science.gov (United States)

    Ghoddousi-Fard, Reza

    2017-11-01

    High rate (1 Hz) GPS and GLONASS phase rate measurements from the global Real Time International GNSS Service (RT-IGS) network are used to monitor ionospheric irregularities. In this paper, impact of different receiver types and satellite constellations on GNSS-derived indices are studied. Constellation dependent background phase noise is quantified at RT-IGS stations for different receiver categories. Improved sampling of the ionosphere is achieved using multiple constellations. Correlation of hourly mean values of dual constellation GNSS indices with hourly magnetic ranges at a co-located auroral magnetic observatory slightly increased compared to when single constellation is used.

  16. Magnetic Implosion for Novel Strength Measurements at High Strain Rates

    Energy Technology Data Exchange (ETDEWEB)

    Lee, H.; Preston, D.L.; Bartsch, R.R.; Bowers, R.L.; Holtkamp, D.; Wright, B.L.

    1998-10-19

    Recently Lee and Preston have proposed to use magnetic implosions as a new method for measuring material strength in a regime of large strains and high strain rates inaccessible to previously established techniques. By its shockless nature, this method avoids the intrinsic difficulties associated with an earlier approach using high explosives. The authors illustrate how the stress-strain relation for an imploding liner can be obtained by measuring the velocity and temperature history of its inner surface. They discuss the physical requirements that lead us to a composite liner design applicable to different test materials, and also compare the code-simulated prediction with the measured data for the high strain-rate experiments conducted recently at LANL. Finally, they present a novel diagnostic scheme that will enable us to remove the background in the pyrometric measurement through data reduction.

  17. A High Rate Tension Device for Characterizing Brain Tissue

    CERN Document Server

    Rashid, Badar; Gilchrist, Michael; 10.1177/1754337112436900

    2013-01-01

    The mechanical characterization of brain tissue at high loading velocities is vital for understanding and modeling Traumatic Brain Injury (TBI). The most severe form of TBI is diffuse axonal injury (DAI) which involves damage to individual nerve cells (neurons). DAI in animals and humans occurs at strains > 10% and strain rates > 10/s. The mechanical properties of brain tissues at these strains and strain rates are of particular significance, as they can be used in finite element human head models to accurately predict brain injuries under different impact conditions. Existing conventional tensile testing machines can only achieve maximum loading velocities of 500 mm/min, whereas the Kolsky bar apparatus is more suitable for strain rates > 100/s. In this study, a custom-designed high rate tension device is developed and calibrated to estimate the mechanical properties of brain tissue in tension at strain rates < 90/s, while maintaining a uniform velocity. The range of strain can also be extended to 100% de...

  18. Systematic Uncertainties in High-Rate Germanium Data

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, Andrew J.; Fast, James E.; Fulsom, Bryan G.; Pitts, William K.; VanDevender, Brent A.; Wood, Lynn S.

    2016-10-06

    For many nuclear material safeguards inspections, spectroscopic gamma detectors are required which can achieve high event rates (in excess of 10^6 s^-1) while maintaining very good energy resolution for discrimination of neighboring gamma signatures in complex backgrounds. Such spectra can be useful for non-destructive assay (NDA) of spent nuclear fuel with long cooling times, which contains many potentially useful low-rate gamma lines, e.g., Cs-134, in the presence of a few dominating gamma lines, such as Cs-137. Detectors in use typically sacrifice energy resolution for count rate, e.g., LaBr3, or visa versa, e.g., CdZnTe. In contrast, we anticipate that beginning with a detector with high energy resolution, e.g., high-purity germanium (HPGe), and adapting the data acquisition for high throughput will be able to achieve the goals of the ideal detector. In this work, we present quantification of Cs-134 and Cs-137 activities, useful for fuel burn-up quantification, in fuel that has been cooling for 22.3 years. A segmented, planar HPGe detector is used for this inspection, which has been adapted for a high-rate throughput in excess of 500k counts/s. Using a very-high-statistic spectrum of 2.4*10^11 counts, isotope activities can be determined with very low statistical uncertainty. However, it is determined that systematic uncertainties dominate in such a data set, e.g., the uncertainty in the pulse line shape. This spectrum offers a unique opportunity to quantify this uncertainty and subsequently determine required counting times for given precision on values of interest.

  19. A Novel Temperature Measurement Approach for a High Pressure Dielectric Barrier Discharge Using Diode Laser Absorption Spectroscopy (Preprint)

    National Research Council Canada - National Science Library

    Leiweke, R. J; Ganguly, B. N

    2006-01-01

    A tunable diode laser absorption spectroscopic technique is used to measure both electronically excited state production efficiency and gas temperature rise in a dielectric barrier discharge in argon...

  20. High-frame-rate echocardiography with reduced sidelobe level.

    Science.gov (United States)

    Hasegawa, Hideyuki; Kanai, Hiroshi

    2012-11-01

    Echocardiography has become an indispensable modality for diagnosis of the heart. It enables observation of the shape of the heart and estimation of global heart function based on B-mode and M-mode imaging. Methods for echocardiographic estimation of myocardial strain and strain rate have also been developed to evaluate regional heart function. Furthermore, it has been recently shown that echocardiographic measurements of transmural transition of myocardial contraction/relaxation and propagation of vibration caused by closure of the heart valve would be useful for evaluation of myocardial function and viscoelasticity. However, such measurements require a frame rate (typically >200 Hz) much higher than that achieved by conventional ultrasonic diagnostic equipment. We have recently realized a high frame rate of about 300 Hz with a full field of view of 90° using diverging transmit beams and parallel receive beamforming. Although high-frame-rate imaging was made possible by this method, the side lobe level was slightly larger than that of the conventional method. To reduce the side lobe level, phase coherence imaging has recently been developed. Using this method, the spatial resolution is improved and the side lobe level is also reduced. However, speckle-like echoes, for example, echoes from the inside of the heart wall, are also suppressed. In the present study, a method for reducing the side lobe level while preserving speckle-like echoes was developed. The side lobe level was evaluated using a wire phantom. The side lobe level of the high-frame-rate imaging using unfocused diverging beams was improved by 13.3 dB by the proposed method. In in vivo measurements, a B-mode image of the heart of a 23-year-old healthy male could be obtained while preserving the speckle pattern in the heart wall at a frame rate of 316 Hz with a full field of view of 90°.

  1. Effects of oxygen gas flow rates and Ga contents on structural properties of Ga-doped ZnO films prepared by ion-plating with a DC arc discharge

    Energy Technology Data Exchange (ETDEWEB)

    Terasako, Tomoaki, E-mail: terasako.tomoaki.mz@ehime-u.ac.jp [Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama-shi, Ehime 790-8577 (Japan); Nomoto, Junichi; Makino, Hisao; Yamamoto, Naoki [Research Institute, Kochi University of Technology, 185 Miyanokuchi, Tosayamada-cho, Kami-shi, Kochi 782-8502 (Japan); Shirakata, Sho [Graduate School of Science and Engineering, Ehime University, 3 Bunkyo-cho, Matsuyama-shi, Ehime 790-8577 (Japan); Yamamoto, Tetsuya [Research Institute, Kochi University of Technology, 185 Miyanokuchi, Tosayamada-cho, Kami-shi, Kochi 782-8502 (Japan)

    2015-12-01

    Structural properties of highly c-axis oriented polycrystalline Ga-doped ZnO (GZO) films prepared by ion-plating with a DC arc discharge were studied in terms of the oxygen gas flow rate (F{sub O2}) introduced into the chamber during the deposition process and the Ga{sub 2}O{sub 3} content in the GZO sintered pellet. The X-ray diffraction (XRD) measurements revealed that the GZO films have the residual compressive stress along the a-axis direction (in-plane) and the tensile stress along the c-axis direction (out-of-plane). The increase in F{sub O2} or the increase in Ga{sub 2}O{sub 3} content was effective for relaxing the in-plane compressive stress induced by the so-called atomic peening effect. The positive correlation between the carrier concentration (n) and the primitive cell volume (V) would be due to the incorporation of Ga atoms substituting Zn sites (Ga{sub Zn}s) together with the generation of n-type intrinsic defects or complex defects. - Highlights: • Films of Ga-doped ZnO (GZO) films were deposited by ion-plating with a DC arc discharge. • Structural properties of GZO films were examined by X-ray diffraction measurements. • GZO films had the residual compressive stress along the a-axis direction. • There was the correlation between the carrier concentration and the cell volume.

  2. Conventional Point-Velocity Records and Surface Velocity Observations for Estimating High Flow Discharge

    Directory of Open Access Journals (Sweden)

    Giovanni Corato

    2014-10-01

    Full Text Available Flow velocity measurements using point-velocity meters are normally obtained by sampling one, two or three velocity points per vertical profile. During high floods their use is inhibited due to the difficulty of sampling in lower portions of the flow area. Nevertheless, the application of standard methods allows estimation of a parameter, α, which depends on the energy slope and the Manning roughness coefficient. During high floods, monitoring of velocity can be accomplished by sampling the maximum velocity, umax, only, which can be used to estimate the mean flow velocity, um, by applying the linear entropy relationship depending on the parameter, M, estimated on the basis of historical observed pairs (um, umax. In this context, this work attempts to analyze if a correlation between α and M holds, so that the monitoring for high flows can be addressed by exploiting information from standard methods. A methodology is proposed to estimate M from α, by coupling the “historical” information derived by standard methods, and “new” information from the measurement of umax surmised at later times. Results from four gauged river sites of different hydraulic and geometric characteristics have shown the robust estimation of M based on α.

  3. Mitigation of divertor heat loads by strike point sweeping in high power JET discharges

    Science.gov (United States)

    Silburn, S. A.; Matthews, G. F.; Challis, C. D.; Frigione, D.; Graves, J. P.; Mantsinen, M. J.; Belonohy, E.; Hobirk, J.; Iglesias, D.; Keeling, D. L.; King, D.; Kirov, K.; Lennholm, M.; Lomas, P. J.; Moradi, S.; Sips, A. C. C.; Tsalas, M.; Contributors, JET

    2017-12-01

    Deliberate periodic movement (sweeping) of the high heat flux divertor strike lines in tokamak plasmas can be used to manage the heat fluxes experienced by exhaust handling plasma facing components, by spreading the heat loads over a larger surface area. Sweeping has recently been adopted as a routine part of the main high performance plasma configurations used on JET, and has enabled pulses with 30 MW plasma heating power and 10 MW radiation to run for 5 s without overheating the divertor tiles. We present analysis of the effectiveness of sweeping for divertor temperature control on JET, using infrared camera data and comparison with a simple 2D heat diffusion model. Around 50% reduction in tile temperature rise is obtained with 5.4 cm sweeping compared to the un-swept case, and the temperature reduction is found to scale slower than linearly with sweeping amplitude in both experiments and modelling. Compatibility of sweeping with high fusion performance is demonstrated, and effects of sweeping on the edge-localised mode behaviour of the plasma are reported and discussed. The prospects of using sweeping in future JET experiments with up to 40 MW heating power are investigated using a model validated against existing experimental data.

  4. Highly variable rates of genome rearrangements between hemiascomycetous yeast lineages.

    Directory of Open Access Journals (Sweden)

    2006-03-01

    Full Text Available Hemiascomycete yeasts cover an evolutionary span comparable to that of the entire phylum of chordates. Since this group currently contains the largest number of complete genome sequences it presents unique opportunities to understand the evolution of genome organization in eukaryotes. We inferred rates of genome instability on all branches of a phylogenetic tree for 11 species and calculated species-specific rates of genome rearrangements. We characterized all inversion events that occurred within synteny blocks between six representatives of the different lineages. We show that the rates of macro- and microrearrangements of gene order are correlated within individual lineages but are highly variable across different lineages. The most unstable genomes correspond to the pathogenic yeasts Candida albicans and Candida glabrata. Chromosomal maps have been intensively shuffled by numerous interchromosomal rearrangements, even between species that have retained a very high physical fraction of their genomes within small synteny blocks. Despite this intensive reshuffling of gene positions, essential genes, which cluster in low recombination regions in the genome of Saccharomyces cerevisiae, tend to remain syntenic during evolution. This work reveals that the high plasticity of eukaryotic genomes results from rearrangement rates that vary between lineages but also at different evolutionary times of a given lineage.

  5. Precise muon drift tube detectors for high background rate conditions

    Energy Technology Data Exchange (ETDEWEB)

    Engl, Albert

    2011-08-04

    The muon spectrometer of the ATLAS-experiment at the Large Hadron Collider consists of drift tube chambers, which provide the precise measurement of trajectories of traversing muons. In order to determine the momentum of the muons with high precision, the measurement of the position of the muon in a single tube has to be more accurate than {sigma}{<=}100 {mu}m. The large cross section of proton-proton-collisions and the high luminosity of the accelerator cause relevant background of neutrons and {gamma}s in the muon spectrometer. During the next decade a luminosity upgrade to 5.10{sup 34} cm{sup -2}s{sup -1} is planned, which will increase the background counting rates considerably. In this context this work deals with the further development of the existing drift chamber technology to provide the required accuracy of the position measurement under high background conditions. Two approaches of improving the drift tube chambers are described: - In regions of moderate background rates a faster and more linear drift gas can provide precise position measurement without changing the existing hardware. - At very high background rates drift tube chambers consisting of tubes with a diameter of 15 mm are a valuable candidate to substitute the CSC muon chambers. The single tube resolution of the gas mixture Ar:CO{sub 2}:N{sub 2} in the ratio of 96:3:1 Vol %, which is more linear and faster as the currently used drift gas Ar:CO{sub 2} in the ratio of 97:3 Vol %, was determined at the Cosmic Ray Measurement Facility at Garching and at high {gamma}-background counting rates at the Gamma Irradiation Facility at CERN. The alternative gas mixture shows similar resolution without background. At high background counting rates it shows better resolution as the standard gas. To analyse the data the various parts of the setup have to be aligned precisely to each other. The change to an alternative gas mixture allows the use of the existing hardware. The second approach are drift tubes

  6. Testing of fiber composites at high strain rates

    Science.gov (United States)

    Daniel, I. M.; Liber, T.

    1978-01-01

    An experimental investigation was conducted to determine strain rate effects in fiber composites. Unidirectional composite specimens of boron/epoxy, graphite/epoxy, S-glass/epoxy and Kevlar/epoxy were tested at tensile strain rates of up to 27 m/m/sec. Longitudinal, transverse and in-plane shear properties, including modulus, Poisson's ratio, strength and ultimate strain, were determined by testing 0-, 90and 10-degree unidirectional coupons. Strains were measured by means of strain gages bonded on the coupons and loads were measured by means of a strain gage load cell. All specimens were loaded in an electrohydraulic loading system. The 0-degree properties which are governed by the fibers do not vary much with strain rate except for the Kevlar/epoxy material which shows an increase in both modulus and strength. The strain rate effects on 90-degree properties were small with a general trend toward higher strength with increasing strain rate. The most noticeable effect was on in-plane shear properties with shear strength values at high strain rates approximately fifteen percent higher than static values.

  7. High triacylglycerol turnover rate in human skeletal muscle

    DEFF Research Database (Denmark)

    Sacchetti, Massimo; Saltin, Bengt; Olsen, David B

    2004-01-01

    could be due to the observed decline in plasma insulin concentration (-74%, P skeletal muscle in post-absorptive healthy individuals is esterified into IMTAG, due to its high turnover rate (29 h pool(-1)). An increase in FA level...... into IMTAG in vastus lateralis muscle was determined during two consecutive 4-h periods (2-6 h and 6-10 h). Fifty to sixty per cent of the FA taken up from the circulation were esterified into IMTAG, whereas 32 and 42% were oxidized between 2-6 and 6-10 h, respectively. IMTAG fractional synthesis rate was 3...

  8. High shear rate rheometry of low-viscosity liquids

    Science.gov (United States)

    Lodge, Arthur S.

    1987-11-01

    A new instrument called LODGE STRESSMETER was developed to measure the shear elasticity and viscosity of general and multigrade oils at high shear rates. This will make possible the measurements of normal stress difference N1 for values of shear rate up to 5 x 10 to the 5th power is temperature of 150 C. New surprising data show (as yet unexplained) the the N1 contribution to the minimum oil film thickness could be as much as 75 percent of the contribution from viscosity. This raises hope for the use of oils with lower viscosity, leading to improved fuel economy and an increase in the range of motorized vehicles.

  9. Ear discharge

    Science.gov (United States)

    ... antibiotic medicines, which are placed in the ear. Antibiotics may be given by mouth if a ruptured eardrum from an ear infection is causing the discharge. Alternative Names Drainage from the ear; Otorrhea; Ear bleeding; ...

  10. Osteomyelitis - discharge

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000297.htm Osteomyelitis - discharge To use the sharing features on this page, please enable JavaScript. You have osteomyelitis , a bone infection caused by bacteria or other ...

  11. Capacitor discharge engineering

    CERN Document Server

    Früngel, Frank B A

    1976-01-01

    High Speed Pulse Technology, Volume III: Capacitor Discharge Engineering covers the production and practical application of capacitor dischargers for the generation and utilization of high speed pulsed of energy in different forms. This nine-chapter volume discusses the principles of electric current, voltage, X-rays, gamma rays, heat, beams of electrons, neutrons and ions, magnetic fields, sound, and shock waves in gases and liquids. Considerable chapters consider the applications of capacitor discharges, such as impulse hardening of steel, ultrapulse welding of precision parts, X-ray flash t

  12. Study of Gas Dynamic Effects in Non-Uniform High Pressure Electrical Discharges.

    Science.gov (United States)

    1980-08-01

    PAGE BEFORE COMPLETING FORM el-REOT . GOVT ACCESSION No. 3. mg91: ATLG UME UD O,.AS.qNMICPFECSIN 1NU IFR 27 May - 2 Augu J.T HPRE’SSLRE ELECTRI CAL DI...addition, in order to achieve high average power output from the pulsed systems, while the systems can be scaled up in size to any practical limit, once...behavior exhibits several features under various conditions. The most promient of these are outlined in Fig. 17a. Many smaller scale perturbations are

  13. Discharge instabilities in high-pressure fluorine based excimer laser gas mixtures

    OpenAIRE

    Mathew, D

    2007-01-01

    Fluorine based excimer lasers such as KrF, ArF and F2 are currently the most powerful sources available in the ultraviolet wavelength range, operating at 248 nm, at 193 nm and at 157 nm, respectively. They are thus of central importance for numerous applications in this range. At these short wavelengths, reaching the laser threshold for an efficient operation, F2-based lasers require to be pumped, in a controlled manner, with very high power densities. This can practically be achieved only vi...

  14. Characteristics of plasma sterilizer using microwave torch plasma with AC high-voltage discharge plasma

    Science.gov (United States)

    Itarashiki, Tomomasa; Hayashi, Nobuya; Yonesu, Akira

    2016-01-01

    Microwave plasma sterilization has recently been attracting attention for medical applications. However, it is difficult to perform low-temperature sterilization in short time periods. Increasing the output power shortens the time required for sterilization but causes the temperature to increase. To overcome this issue, we have developed a hybrid plasma system that combines a microwave torch plasma and a high-voltage mesh plasma, which allows radicals to be produced at low temperatures. Using this system, successful sterilization was shown to be possible in a period of 45 min at a temperature of 41 °C.

  15. High Data Rate Optical Wireless Communications Based on Ultraviolet Band

    KAUST Repository

    Sun, Xiaobin

    2017-10-01

    Optical wireless communication systems based on ultraviolet (UV)-band has a lot inherent advantages, such as low background solar radiation, low device dark noise. Besides, it also has small restrictive requirements for PAT (pointing, acquisition, and tracking) because of its high atmospheric scattering with molecules and aerosols. And these advantages are driving people to explore and utilize UV band for constructing and implementing a high-data-rate, less PAT communication links, such as diffuse-line-of-sight links (diffuse-LOS) and non-line-of-sight (NLOS). The responsivity of the photodetector at UV range is far lower than that of visible range, high power UV transmitters which can be easily modulated are under investigation. These factors make it is hard to realize a high-data-rate diffuse-LOS or NLOS UV communication links. To achieve a UV link mentioned above with current devices and modulation schemes, this thesis presents some efficient modulation schemes and available devices for the time being. Besides, a demonstration of ultraviolet-B (UVB) communication link is implemented utilizing quadrature amplitude modulation (QAM) orthogonal frequency-division multiplexing (OFDM). The demonstration is based on a 294-nm UVB-light-emitting-diode (UVB-LED) with a full-width at half-maximum (FWHM) of 9 nm, and according to the measured L-I-V curve, we set the bias voltage as 7V for maximum the ac amplitude and thus get a high signal-noise-ratio (SNR) channel, and the light output power is 190 μW with such bias voltage. Besides, there is a unique silica gel lens on top of the LED to concentrate the beam. A -3-dB bandwidth of 29 MHz was measured and a high-speed near-solar-blind communication link with a data rate of 71 Mbit/s was achieved using 8-QAM-OFDM at perfect alignment, and 23.6 Mbit/s using 2-QAM-OFDM when the angle subtended by the pointing direction of the UVB-LED and photodetector (PD) is 12 degrees, thus establishing a diffuse-line-of-sight (LOS) link

  16. Facile Solution Route to Synthesize Nanostructure Li4Ti5O12 for High Rate Li-Ion Battery

    Directory of Open Access Journals (Sweden)

    M. V. Tran

    2016-01-01

    Full Text Available High rate Li-ion batteries have been given great attention during the last decade as a power source for hybrid electric vehicles (HEVs, EVs, etc. due to the highest energy and power density. These lithium batteries required a new design of material structure as well as innovative electrode materials. Among the promising candidates, spinel Li4Ti5O12 has been proposed as a high rate anode to replace graphite anode because of high capacity and a negligible structure change during intercalation of lithium. In this work, we synthesized a spinel Li4Ti5O12 in nanosize by a solution route using LiOH and Ti(OBu4 as precursor. An evaluation of structure and morphology by XRD and SEM exhibited pure spinel phase Li4Ti5O12 and homogenous nanoparticles around 100 nm. In the charge-discharge test, nanospinel Li4Ti5O12 presents excellent discharge capacity 160 mAh/g at rate C/10, as well as good specific capacities of 120, 110, and 100 mAh/g at high rates C, 5C and 10C, respectively.

  17. Dynamic High-Temperature Characterization of an Iridium Alloy in Compression at High Strain Rates

    Energy Technology Data Exchange (ETDEWEB)

    Song, Bo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Experimental Environment Simulation Dept.; Nelson, Kevin [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Mechanics of Materials Dept.; Lipinski, Ronald J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Nuclear Fuel Cycle Technology Dept.; Bignell, John L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Structural and Thermal Analysis Dept.; Ulrich, G. B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Radioisotope Power Systems Program; George, E. P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Radioisotope Power Systems Program

    2014-06-01

    Iridium alloys have superior strength and ductility at elevated temperatures, making them useful as structural materials for certain high-temperature applications. However, experimental data on their high-temperature high-strain-rate performance are needed for understanding high-speed impacts in severe elevated-temperature environments. Kolsky bars (also called split Hopkinson bars) have been extensively employed for high-strain-rate characterization of materials at room temperature, but it has been challenging to adapt them for the measurement of dynamic properties at high temperatures. Current high-temperature Kolsky compression bar techniques are not capable of obtaining satisfactory high-temperature high-strain-rate stress-strain response of thin iridium specimens investigated in this study. We analyzed the difficulties encountered in high-temperature Kolsky compression bar testing of thin iridium alloy specimens. Appropriate modifications were made to the current high-temperature Kolsky compression bar technique to obtain reliable compressive stress-strain response of an iridium alloy at high strain rates (300 – 10000 s-1) and temperatures (750°C and 1030°C). Uncertainties in such high-temperature high-strain-rate experiments on thin iridium specimens were also analyzed. The compressive stress-strain response of the iridium alloy showed significant sensitivity to strain rate and temperature.

  18. Silane Discharge Ion Chemistry.

    Science.gov (United States)

    Chatham, Robert Hood, III

    We have studied silane dc, rf and dc proximity discharges, using mass spectroscopic measurements of the positive ions as a detailed diagnostic for the type of discharge used to produce hydrogenated amorphous silicon solar photovoltaic cells. The properties and quality of these films depends in a very complex way upon the interactions of the many reactive neutral and ion species in the discharge. We have developed qualitative models of the ion chemical processes in these discharges from our measurements. Knowledge of the ion-molecule and electron-molecule collision cross sections is important to any attempt at understanding silane discharge chemistry. Consequently, we have measured the electron impact ionization cross sections for silane and disilane, and for comparison purposes also for methane and ethane. In addition, we have measured the rate coefficients for charge exchange reactions of He('+), Ne('+), and Ar('+) with silane, disilane, methane, and ethane, as these are important to understanding discharges in inert gas-silane mixtures. We have developed a detailed quantitative model of the cathode sheath region of a silane dc discharge, by extending the best recent calculation of the electron motion in the sheath to a self-consistent form which includes the ion motion. This model is used with comparison of silane dc discharge data to diagnose the ion chemistry occurring in the sheath region of silane dc discharge. The understanding of the discharge ion chemical processes that we have gained in this study represent an important step toward understanding the chemical and physical processes leading to film growth.

  19. Molten Salt Synthesis and High Rate Performance of the ‘‘Desert-Rose’’ form of LiCoO2

    Energy Technology Data Exchange (ETDEWEB)

    H Chen; C Grey

    2011-12-31

    The synthesis of a novel nanostructure of LiCoO{sub 2}, and its performance as a cathode for a high-rate lithium ion battery, is described. The LiCoO{sub 2} nanostructure resembles the morphology of a known natural mineral: 'desert rose' gypsum. A range of measurement techniques are used to investigate the growth mechanism of this structure and the origin of its high rate charge/discharge properties.

  20. CO-AXIAL DISCHARGES

    Science.gov (United States)

    Luce, J.S.; Smith, L.P.

    1960-11-22

    A method and apparatus are given for producing coaxial arc discharges in an evacuated enclosure and within a strong, confining magnetic field. The arcs are maintained at a high potential difference. Electrons will diffuse to the more positive arc from the negative arc, and positive ions will diffuse from the more positive arc to the negative arc. Coaxial arc discharges have the advantage that ions which return to strike the positive arc discharge will lose no energy since they do not strike a solid wall or electrode. Those discharges are useful in confining an ionized plasma between the discharges, and have the advantage of preventing impurities from the walls of the enclosure from entering ihe plasma area because of the arc barrier set up bv the cylindrical outer arc.

  1. Monolithic Graphene Trees as Anode Material for Lithium Ion Batteries with High C-Rates.

    Science.gov (United States)

    Jeong, Seung Yol; Yang, Sunhye; Jeong, Sooyeon; Kim, Ick Jun; Jeong, Hee Jin; Han, Joong Tark; Baeg, Kang-Jun; Lee, Geon-Woong

    2015-06-01

    Monolithically structured reduced graphene oxide (rGO), prepared from a highly concentrated and conductive rGO paste, is introduced as an anode material for lithium ion batteries with high rate capacities. This is achieved by a mixture of rGO paste and the water-soluble polymer sodium carboxymethylcellulose (SCMC) with freeze drying. Unlike previous 3D graphene porous structures, the monolithic graphene resembles densely branched pine trees and has high mechanical stability with strong adhesion to the metal electrodes. The structures contain numerous large surface area open pores that facilitate lithium ion diffusion, while the strong hydrogen bonding between the graphene layers and SCMC provides high conductivity and reduces the volume changes that occur during cycling. Ultrafast charge/discharge rates are obtained with outstanding cycling stability and the capacities are higher than those reported for other anode materials. The fabrication process is simple and straightforward to adjust and is therefore suitable for mass production of anode electrodes for commercial applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. High Pressure Burn Rate Measurements on an Ammonium Perchlorate Propellant

    Energy Technology Data Exchange (ETDEWEB)

    Glascoe, E A; Tan, N

    2010-04-21

    High pressure deflagration rate measurements of a unique ammonium perchlorate (AP) based propellant are required to design the base burn motor for a Raytheon weapon system. The results of these deflagration rate measurements will be key in assessing safety and performance of the system. In particular, the system may experience transient pressures on the order of 100's of MPa (10's kPSI). Previous studies on similar AP based materials demonstrate that low pressure (e.g. P < 10 MPa or 1500 PSI) burn rates can be quite different than the elevated pressure deflagration rate measurements (see References and HPP results discussed herein), hence elevated pressure measurements are necessary in order understand the deflagration behavior under relevant conditions. Previous work on explosives have shown that at 100's of MPa some explosives will transition from a laminar burn mechanism to a convective burn mechanism in a process termed deconsolidative burning. The resulting burn rates that are orders-of-magnitude faster than the laminar burn rates. Materials that transition to the deconsolidative-convective burn mechanism at elevated pressures have been shown to be considerably more violent in confined heating experiments (i.e. cook-off scenarios). The mechanisms of propellant and explosive deflagration are extremely complex and include both chemical, and mechanical processes, hence predicting the behavior and rate of a novel material or formulation is difficult if not impossible. In this work, the AP/HTPB based material, TAL-1503 (B-2049), was burned in a constant volume apparatus in argon up to 300 MPa (ca. 44 kPSI). The burn rate and pressure were measured in-situ and used to calculate a pressure dependent burn rate. In general, the material appears to burn in a laminar fashion at these elevated pressures. The experiment was reproduced multiple times and the burn rate law using the best data is B = (0.6 {+-} 0.1) x P{sup (1.05{+-}0.02)} where B is the burn

  3. Ionization processes in combined high-voltage nanosecond - laser discharges in inert gas

    Science.gov (United States)

    Starikovskiy, Andrey; Shneider, Mikhail; PU Team

    2016-09-01

    Remote control of plasmas induced by laser radiation in the atmosphere is one of the challenging issues of free space communication, long-distance energy transmission, remote sensing of the atmosphere, and standoff detection of trace gases and bio-threat species. Sequences of laser pulses, as demonstrated by an extensive earlier work, offer an advantageous tool providing access to the control of air-plasma dynamics and optical interactions. The avalanche ionization induced in a pre-ionized region by infrared laser pulses where investigated. Pre-ionization was created by an ionization wave, initiated by high-voltage nanosecond pulse. Then, behind the front of ionization wave extra avalanche ionization was initiated by the focused infrared laser pulse. The experiment was carried out in argon. It is shown that the gas pre-ionization inhibits the laser spark generation under low pressure conditions.

  4. Novel Carbon Materials in the Cathode Formulation for High Rate Rechargeable Hybrid Aqueous Batteries

    Directory of Open Access Journals (Sweden)

    Xiao Zhu

    2017-11-01

    Full Text Available Novel carbon materials, carbon nanotubes (CNTs and porous graphene (PG, were exploited and used as conductive additives to improve the rate performance of LiMn2O4 cathode for the rechargeable aqueous Zn/LiMn2O4 battery, namely the rechargeable hybrid aqueous battery (ReHAB. Thanks to the long-range conductivity and stable conductive network provided by CNTs, the rate and cycling performances of LiMn2O4 cathode in ReHAB are highly improved—up to about 100 mAh·g−1 capacity is observed at 10 C (1 C = 120 mAh·g−1. Except for CNTs, porous graphene (PG with a high surface area, an abundant porous structure, and an excellent electrical conductivity facilitates the transportation of Li ions and electrons, which can also obviously enhance the rate capability of the ReHAB. This is important because the ReHAB could be charged/discharged in a few minutes, and this leads to potential application of the ReHAB in automobile industry.

  5. 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%.

  6. The cataphoretic emitter effect exhibited in high intensity discharge lamp electrodes

    Science.gov (United States)

    Mentel, Juergen

    2018-01-01

    A mono-layer of atoms, electropositive with respect to the substrate atoms, forms a dipole layer, reducing its work function. Such a layer is generated by diffusion of emitter material from the interior of the substrate, by vapour deposition or by deposition of emitter material onto arc electrodes by cataphoresis. This cataphoretic emitter effect is investigated within metal halide lamps with transparent YAG ceramic burners, and within model lamps. Within the YAG lamps, arcs are operated with switched-dc current between rod shaped tungsten electrodes in high pressure Hg vapour seeded with metal iodides. Within the model lamps, dc arcs are operated between rod-shaped tungsten electrodes—one doped—in atmospheric pressure Ar. Electrode temperatures are determined by 1λ -pyrometry, combined with simulation of the electrode heat balance. Plasma temperatures, atom and ion densities of emitter material are determined by emission and absorption spectroscopy. Phase resolved measurements in YAG lamps seeded with CeI3, CsI, DyI3, TmI3 and LaI3 show, within the cathodic half period, a reduction of the electrode temperature and an enhanced metal ion density in front of the electrode, and an opposite behavior after phase reversal. With increasing operating frequency, the state of the cathode overlaps onto the anodic phase—except for Cs, being low in adsorption energy. Generally, the phase averaged electrode tip temperature is reduced by seeding a lamp with emitter material; its height depends on admixtures. Measurements at tungsten electrodes doped with ThO2, La2O3 and Ce2O3 within the model lamp show that evaporated emitter material is redeposited by an emitter ion current onto the electrode surface. It reduces the work function of tungsten cathodes above the evaporation temperature of the emitter material, too; and also of cold anodes, indicating a field reversal in front of them. The formation of an emitter spot at low cathode temperature and high emitter material

  7. Evidence of current free double layer in high density helicon discharge

    Energy Technology Data Exchange (ETDEWEB)

    Ganguli, A. [Centre for Energy Studies, Indian Institute of Technology, New Delhi 110016 (India); Sahu, B. B. [Department of Applied Sciences and Humanities, Dronacharya College of Engineering, Gurgaon 123506 (India); Tarey, R. D. [Department of Physics, Indian Institute of Technology, New Delhi 110016 (India)

    2013-01-15

    This paper investigates the formation of double layer (DL) in helicon plasmas. In the experiment, argon plasma production is using the excitation of m = -1 helicon mode with magnetic mirror field with high mirror ratio of {approx}1:1.7. We have specifically used the radio frequency compensated Langmuir probe (LP) to measure the relevant plasma parameters simultaneously so as to investigate the details about the plasma production. The DL, which consists of both warm and bulk populations towards higher potential region and only dense bulk plasmas towards the lower potential region downstream the antenna, is present in the transition region. LP measurements also show an abrupt fall of density along with a potential drop of about 20 V and (e {Delta}V{sub p}/k T{sub e}) Almost-Equal-To 12 within a few cm. The potential drop is equal to the difference of the electron temperatures between the two plasma regions forming the DL, which is present in the plateau region of mirror, unlike in several prior studies on the DL formation in the region of strong gradients in the magnetic field. The DL is strong, current-free, electric double-layer with estimated thickness of about 10 Debye lengths.

  8. A Study of Preliminary Breakdown and Return Stroke Processes in High-Intensity Negative Lightning Discharges

    Directory of Open Access Journals (Sweden)

    Yanan Zhu

    2016-10-01

    Full Text Available Using an automated data processing algorithm, we examined electric field records of 5498 negative cloud-to-ground flashes reported by the U.S. National Lightning Detection Network (NLDN within 50 to 500 km of the Lightning Observatory in Gainesville (LOG, Florida. Out of the 5498 flashes, 3496 (64% had detectable preliminary breakdown (PB pulse trains. Only 3077 flashes with a single PB pulse train and NLDN-reported first-return-stroke (RS peak current ≥50 kA were selected for detailed analysis. The arithmetic mean values of PB pulse train duration, PB-RS interval, and PB/RS pulse peak ratio were 2.7 ms, 8.8 ms, and 0.15, respectively. The PB-RS interval was found to decrease with increasing RS peak current (Spearman correlation coefficient was statistically significant and equal to −0.80. The range-normalized PB pulse peak exhibited statistically significant positive correlation with the RS peak current, with Spearman correlation coefficient being 0.48. Thus, it appears that the high-intensity (≥50 kA negative lightning is characterized by shorter (and, by inference, faster stepped leaders and more pronounced PB pulse trains.

  9. Advanced structure of cathode for gas discharge lamp of super high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Kruglenya, P.A.; Maslennikov, O.Y

    2003-06-15

    This paper presents a new cathode structure for short length arc-plasma circular lamp DRKs2-1500 filled with mercury-xenon of super high pressure. A conventional cathode of thoriated tungsten was replaced by a new structure of tungsten-barium. This cathode has emitting surface of cavity form which enables to reduce active material evaporation from the surface and to increase emission stability. It was found that light parameters of the lamp depend on the geometry of its electrodes. Fusing and evaporation of the cathode material result in a cathode size change and lead to changes of arc-plasma parameters, blackening of the lamp envelope and decreasing luminous flux intensity. The tests showed that the lamp service life with the new cathode grows as much as 2-3 times. Optimization of the cathode cavity geometric size is expected to enlarge the lamp service life up to 3000-5000 h (guaranteed service life of a lamp with usual structure of cathode is 500 h)

  10. Novel design of high voltage pulse source for efficient dielectric barrier discharge generation by using silicon diodes for alternating current.

    Science.gov (United States)

    Truong, Hoa Thi; Hayashi, Misaki; Uesugi, Yoshihiko; Tanaka, Yasunori; Ishijima, Tatsuo

    2017-06-01

    This work focuses on design, construction, and optimization of configuration of a novel high voltage pulse power source for large-scale dielectric barrier discharge (DBD) generation. The pulses were generated by using the high-speed switching characteristic of an inexpensive device called silicon diodes for alternating current and the self-terminated characteristic of DBD. The operation started to be powered by a primary DC low voltage power supply flexibly equipped with a commercial DC power supply, or a battery, or DC output of an independent photovoltaic system without transformer employment. This flexible connection to different types of primary power supply could provide a promising solution for the application of DBD, especially in the area without power grid connection. The simple modular structure, non-control requirement, transformer elimination, and a minimum number of levels in voltage conversion could lead to a reduction in size, weight, simple maintenance, low cost of installation, and high scalability of a DBD generator. The performance of this pulse source has been validated by a load of resistor. A good agreement between theoretically estimated and experimentally measured responses has been achieved. The pulse source has also been successfully applied for an efficient DBD plasma generation.

  11. Design and construction of prototype transversely excited atmospheric (TEA nitrogen laser energized by a high voltage electrical discharge

    Directory of Open Access Journals (Sweden)

    Mukhtar Hussain

    2015-07-01

    Full Text Available The present study reports design and construction, of a prototype of Transversely Excited Atmospheric (TEA nitrogen laser, and a high voltage power supply to excite N2 gas in air, while air is used as an active lasing medium. A Blumlein line discharge circuit is used for operation of this laser. The high voltage is generated by a fly back transformer based power supply varying from 10 kV to 20 kV. The wavelength (337.1 nm of TEA nitrogen laser is measured employing a standard commercial spectrometer and the laser output energy of 300 μJ is measured from the constructed system. Different parameters such as beam profile, laser output spectrum, laser efficiency, and variation of E/P (Electrical field/Pressure value with respect to input voltage and electrodes separations are studied in order to optimize the overall operational efficiency of present nitrogen laser. The analysis of the high voltage prototype appeared in this designed source has also been made and described in this paper.

  12. Novel design of high voltage pulse source for efficient dielectric barrier discharge generation by using silicon diodes for alternating current

    Science.gov (United States)

    Truong, Hoa Thi; Hayashi, Misaki; Uesugi, Yoshihiko; Tanaka, Yasunori; Ishijima, Tatsuo

    2017-06-01

    This work focuses on design, construction, and optimization of configuration of a novel high voltage pulse power source for large-scale dielectric barrier discharge (DBD) generation. The pulses were generated by using the high-speed switching characteristic of an inexpensive device called silicon diodes for alternating current and the self-terminated characteristic of DBD. The operation started to be powered by a primary DC low voltage power supply flexibly equipped with a commercial DC power supply, or a battery, or DC output of an independent photovoltaic system without transformer employment. This flexible connection to different types of primary power supply could provide a promising solution for the application of DBD, especially in the area without power grid connection. The simple modular structure, non-control requirement, transformer elimination, and a minimum number of levels in voltage conversion could lead to a reduction in size, weight, simple maintenance, low cost of installation, and high scalability of a DBD generator. The performance of this pulse source has been validated by a load of resistor. A good agreement between theoretically estimated and experimentally measured responses has been achieved. The pulse source has also been successfully applied for an efficient DBD plasma generation.

  13. High-rate measurement-device-independent quantum cryptography

    DEFF Research Database (Denmark)

    Pirandola, Stefano; Ottaviani, Carlo; Spedalieri, Gaetana

    2015-01-01

    Quantum cryptography achieves a formidable task - the remote distribution of secret keys by exploiting the fundamental laws of physics. Quantum cryptography is now headed towards solving the practical problem of constructing scalable and secure quantum networks. A significant step in this direction...... than those currently achieved. Our protocol could be employed to build high-rate quantum networks where devices securely connect to nearby access points or proxy servers....

  14. MIMO-OFDM for High Rate Underwater Acoustic Communications

    Science.gov (United States)

    2009-10-01

    Doppler estimation The channel Doppler effect can be viewed as caused by carrier frequency offsets (CFO) among the transmitters and the receivers [14...at es in H z 500m 1500m Fig. 4. Doppler estimates for one packet of 64 OFDM blocks at receiver 1; this Doppler shift is due to unintentional...IEEE JOURNAL OF OCEANIC ENGINEERING (TO APPEAR) 1 MIMO- OFDM for High Rate Underwater Acoustic Communications Baosheng Li, Student Member, IEEE, Jie

  15. Trends in drop out, drug free discharge and rates of re-presentation: a retrospective cohort study of drug treatment clients in the North West of England

    Directory of Open Access Journals (Sweden)

    McVeigh Jim

    2006-08-01

    Full Text Available Abstract Background Governments aim to increase treatment participation by problematic drug users. In the UK this has been achieved by fiscal investment, an expanded workforce, reduced waiting times and coercive measures (usually criminal justice (CJ led. No assessment of these measures on treatment outcomes has been made. Using established monitoring systems we assessed trends in 'dropped out' and 'discharged drug free' (DDF, since the launch of the national drug strategy, and rates of treatment re-presentation for these cohorts. Methods A longitudinal dataset of drug users (1997 to 2004/05, n = 26,415 was used to identify people who dropped out of, and were DDF from, services for years 1998 to 2001/02, and re-presentations of these people in years to 2004/05. Trends in drop out and DDF, baseline comparisons of those DDF and those who dropped out and outcome comparisons for those referred from the CJ system versus other routes of referral were examined using chi square. Logistic regression analyses identified variables predicting drop out versus DDF and subsequent re-presentation versus no re-presentation. Results The proportion of individuals dropping out has increased from 7.2% in 1998 to 9.6% in 2001/02 (P Conclusion Increasing numbers in treatment is associated with an increased proportion dropping out and an ever-smaller proportion DDF. Rates of drop out are significantly higher for those coerced into treatment via the CJ system. Rates of re-presentation are similar for those dropping out and those DDF. Encouragingly, those who need to re-engage with treatment, particularly those who drop out, are doing so more quickly. The impact of coercion on treatment outcomes and the appropriateness of aftercare provision require further consideration.

  16. One-Pot Hydrothermal Synthesis of LiMn2O4 Cathode Material with Excellent High-Rate and Cycling Properties

    Science.gov (United States)

    Jiang, Qianqian; Wang, Xingyao; Zhang, Han

    2016-08-01

    The spinel LiMn2O4 was prepared by a one-step hydrothermal method using acetone as the reductant under different hydrothermal temperatures. X-ray diffraction and scanning electron microscopy analysis indicated that optimal LiMn2O4 particles (LMO-120) were synthesized at the temperature of 120°C and the particles were well distributed and about 410 nm in size. Electrochemical performance showed that the as-prepared LiMn2O4 particles exhibited a higher initial discharge capacity than commercial LiMn2O4 (131.5 mAh g-1 versus 115.6 mAh g-1 at 0.2 C). An excellent discharge capacity retention rate of 94.07% was observed after 60 charge-discharge cycles. On the other hand, when cycled at the high rate of 1 C, the optimal LiMn2O4 in this work showed a high discharge capacity of 107.5 mAh g-1 in contrast to only 92.3 mAh g-1 of the commercial LiMn2O4. These results indicate that LMO-120 showed excellent electrochemical performance, especially the prolonged cycling life and high-rate performance, which suggested that this spinel LiMn2O4 has promise for practical application as a high-rate cathode material for lithium ion batteries.

  17. Avalanche photo-detection for high data rate applications

    Science.gov (United States)

    Coldenstrodt-Ronge, H. B.; Silberhorn, C.

    2007-10-01

    Avalanche photo-detection is commonly used in applications which require single-photon sensitivity. We examine the limits of using avalanche photo-diodes (APD) for characterizing photon statistics at high data rates. To identify the regime of linear APD operation, we employ a ps-pulsed diode laser with variable repetition rates between 0.5 MHz and 80 MHz. We modify the mean optical power of the coherent pulses by applying different levels of well-calibrated attenuation. The linearity at high repetition rates is limited by the APD dead time and a nonlinear response arises at higher photon-numbers due to multiphoton events. Assuming Poissonian input-light statistics we ascertain the effective mean photon-number of the incident light with high accuracy. Time multiplexed detectors (TMD) allow us to accomplish photon-number resolution by 'photon chopping'. This detection setup extends the linear response function to higher photon-numbers and statistical methods may be used to compensate for nonlinearity. We investigate this effect, compare it to the single APD case and show the validity of the convolution treatment in the TMD data analysis.

  18. Semi-solid electrodes having high rate capability

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Yet-Ming; Duduta, Mihai; Holman, Richard; Limthongkul, Pimpa; Tan, Taison

    2017-11-28

    Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode and a semi-solid cathode. The semi-solid cathode includes a suspension of an active material of about 35% to about 75% by volume of an active material and about 0.5% to about 8% by volume of a conductive material in a non-aqueous liquid electrolyte. An ion-permeable membrane is disposed between the anode and the semi-solid cathode. The semi-solid cathode has a thickness of about 250 .mu.m to about 2,000 .mu.m, and the electrochemical cell has an area specific capacity of at least about 7 mAh/cm.sup.2 at a C-rate of C/4. In some embodiments, the semi-solid cathode slurry has a mixing index of at least about 0.9.

  19. Electrical breakdown and optical emission properties of high pressure pulsed RF gas discharges

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, S.R.; Hurst, G.S. [Pellissippi International, Oak Ridge, TN (United States)]|[Consultec Scientific, Inc., Knoxville, TN (United States); Gibson, W.A. [Pellissippi International, Oak Ridge, TN (United States); Turner, J.E.; Hamm, R.N. [Oak Ridge National Lab., TN (United States); Wright, H.A. [Consultec Scientific, Inc., Knoxville, TN (United States)

    1994-06-01

    A fundamentally new technique for the measurement of the number of subexcitation electrons produced by the passage of ionizing radiation through a gas has ben developed by us during the past few years. The new detector is based on the digital characterization of the electrons in the particle track produced by the ionizing radiation where the charged particle track is registered by measuring the number of electrons found in given subvolumes of the gas in the ionization chamber. The track is thus characterized by a set of integers in each volume clement, from which parameters such as the track length and energy can be measured. We have specifically developed this technique for use in the field of microdosimetry, where the study of the fluctuations in the energy deposition in the charged particle track on the order of the molecular to cellular dimensions is important in understanding the chemical and biological effects of ionizing radiation. If the charged particle is a recoil nucleus produced by a neutron interaction, the energy deposited and the linear energy transfer can be inferred from this information, allowing the detector to act as neutron spectrometer. In this paper the experimental apparatus used to make these measurements and the optical and pulsed RF electric field optimization we have performed are described. Images of particle tracks produced by {alpha} and {beta} particles, and recoil protons from the interaction of high energy neutrons with hydrogenous materials, are also presented to illustrate the sensitivity and track imaging resolution. The quality of the information gained from the detector is a very sensitive function of the gas mixture constituents, purities and pressures used in the chamber, along with the magnitude, duration, and frequency of the pulsed RF electric field.

  20. Qualifying plasma diagnostics for a high power microwave background of ECRH heated discharges

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, M.; Baldzuhn, J.; Endler, M.; Laux, M.; Zhang, D.; Laqua, H.P.; Noke, F.; Purps, F.; Ewert, K. [Max-Planck Institut fur Plasmaphysik, EURATOM Association, D-17491 Greifswald (Germany); Oosterbeek, J.W. [Technische Universiteit Eindhoven, Den Doelch 2, 5612 AZ Eindhoven (Netherlands); Jimenez, R. [Associacion EURATOM/CIEMAT, av. Complutense 22, 28040, Madrid (Spain)

    2011-07-01

    Microwave background radiation resulting from multiple reflected unabsorbed ECRH / ECCD power may cause severe problems for microwave absorbing in-vessel components such as gaskets, bellows, windows, isolators and cable insulations in particular during long pulse operation. For qualifying in-vessel components of W7-X in the environment of an isotropic 140 GHz radiation the Microwave Stray Radiation Launch facility, MISTRAL is operated at IPP. Power flux densities of 10-40 kW/m{sup 2} are obtained with a pulsed power gyrotron launching the microwave via a corrugated transmission line and a vacuum window to the MISTRAL vessel. The focus of the program was on cable isolations as required e.g. for in-vessel magnetic diagnostics. Sufficient shielding is obtained in nearly closed metal pipes only. Cryo pumps require a temperature < 12 K where Hydrogen desorption starts. The cryo pumps are usually shielded from plasma radiation by so called chevron structures. It is investigated whether coating of these chevrons with a microwave absorbing layer yields a sufficient reduction of the stray radiation level to ensure cryo pump operation. Diagnostic windows have been tested also. Although the temperature rise even of uncooled ZnSe and quartz windows at 10 kW/m{sup 2} is uncritical with respect to damage the associated refractive index changes may be too high for some diagnostic purposes e.g. for interferometry. A possible shielding are meshes or {mu}W absorbing coatings. Integrated diagnostic mock-ups such as for the diamagnetic loop, the inner Rogowski coils, Mirnov coils and the bolometer head also have been tested

  1. Hip fracture - discharge

    Science.gov (United States)

    Inter-trochanteric fracture repair - discharge; Subtrochanteric fracture repair - discharge; Femoral neck fracture repair - discharge; Trochanteric fracture repair - discharge; Hip pinning surgery - ...

  2. Three-dimensional graphene foam supported Fe₃O₄ lithium battery anodes with long cycle life and high rate capability.

    Science.gov (United States)

    Luo, Jingshan; Liu, Jilei; Zeng, Zhiyuan; Ng, Chi Fan; Ma, Lingjie; Zhang, Hua; Lin, Jianyi; Shen, Zexiang; Fan, Hong Jin

    2013-01-01

    Fe3O4 has long been regarded as a promising anode material for lithium ion battery due to its high theoretical capacity, earth abundance, low cost, and nontoxic properties. However, up to now no effective and scalable method has been realized to overcome the bottleneck of poor cyclability and low rate capability. In this article, we report a bottom-up strategy assisted by atomic layer deposition to graft bicontinuous mesoporous nanostructure Fe3O4 onto three-dimensional graphene foams and directly use the composite as the lithium ion battery anode. This electrode exhibits high reversible capacity and fast charging and discharging capability. A high capacity of 785 mAh/g is achieved at 1C rate and is maintained without decay up to 500 cycles. Moreover, the rate of up to 60C is also demonstrated, rendering a fast discharge potential. To our knowledge, this is the best reported rate performance for Fe3O4 in lithium ion battery to date.

  3. High Strain Rate and Shock-Induced Deformation in Metals

    Science.gov (United States)

    Ravelo, Ramon

    2012-02-01

    Large-scale non-equilibrium molecular Dynamics (MD) simulations are now commonly used to study material deformation at high strain rates (10^9-10^12 s-1). They can provide detailed information-- such as defect morphology, dislocation densities, and temperature and stress profiles, unavailable or hard to measure experimentally. Computational studies of shock-induced plasticity and melting in fcc and bcc single, mono-crystal metals, exhibit generic characteristics: high elastic limits, large directional anisotropies in the yield stress and pre-melting much below the equilibrium melt temperature for shock wave propagation along specific crystallographic directions. These generic features in the response of single crystals subjected to high strain rates of deformation can be explained from the changes in the energy landscape of the uniaxially compressed crystal lattice. For time scales relevant to dynamic shock loading, the directional-dependence of the yield strength in single crystals is shown to be due to the onset of instabilities in elastic-wave propagation velocities. The elastic-plastic transition threshold can accurately be predicted by a wave-propagation stability analysis. These strain-induced instabilities create incipient defect structures, which can be quite different from the ones, which characterize the long-time, asymptotic state of the compressed solid. With increase compression and strain rate, plastic deformation via extended defects gives way to amorphization associated with the loss in shear rigidity along specific deformation paths. The hot amorphous or (super-cooled liquid) metal re-crystallizes at rates, which depend on the temperature difference between the amorphous solid and the equilibrium melt line. This plastic-amorphous transition threshold can be computed from shear-waves stability analyses. Examples from selected fcc and bcc metals will be presented employing semi-empirical potentials of the embedded atom method (EAM) type as well as

  4. Scale dependence of rock friction at high work rate

    Science.gov (United States)

    Yamashita, Futoshi; Fukuyama, Eiichi; Mizoguchi, Kazuo; Takizawa, Shigeru; Xu, Shiqing; Kawakata, Hironori

    2015-12-01

    Determination of the frictional properties of rocks is crucial for an understanding of earthquake mechanics, because most earthquakes are caused by frictional sliding along faults. Prior studies using rotary shear apparatus revealed a marked decrease in frictional strength, which can cause a large stress drop and strong shaking, with increasing slip rate and increasing work rate. (The mechanical work rate per unit area equals the product of the shear stress and the slip rate.) However, those important findings were obtained in experiments using rock specimens with dimensions of only several centimetres, which are much smaller than the dimensions of a natural fault (of the order of 1,000 metres). Here we use a large-scale biaxial friction apparatus with metre-sized rock specimens to investigate scale-dependent rock friction. The experiments show that rock friction in metre-sized rock specimens starts to decrease at a work rate that is one order of magnitude smaller than that in centimetre-sized rock specimens. Mechanical, visual and material observations suggest that slip-evolved stress heterogeneity on the fault accounts for the difference. On the basis of these observations, we propose that stress-concentrated areas exist in which frictional slip produces more wear materials (gouge) than in areas outside, resulting in further stress concentrations at these areas. Shear stress on the fault is primarily sustained by stress-concentrated areas that undergo a high work rate, so those areas should weaken rapidly and cause the macroscopic frictional strength to decrease abruptly. To verify this idea, we conducted numerical simulations assuming that local friction follows the frictional properties observed on centimetre-sized rock specimens. The simulations reproduced the macroscopic frictional properties observed on the metre-sized rock specimens. Given that localized stress concentrations commonly occur naturally, our results suggest that a natural fault may lose its

  5. Carbon-oxygen reaction efficiency in air gap switch with graphite electrodes under high current pulse discharge

    Science.gov (United States)

    Dai, Hongyu; Li, Lee; Peng, Ming-yang; Xiong, Jiaming; Wu, Haibo; Yu, Bin

    2017-12-01

    In order to reduce the effect of residual carbon on the insulation performance, after the GW-hundreds kiloampere graphite-electrode switch turning on, the chemical kinetics of the carbon-oxygen reaction is analyzed. The capacitive pulsed experimental circuit is used to reconstruct the actual condition of high power and high current discharge. The carbon-oxygen reaction efficiency is analyzed using a Fourier transform infrared spectrometer and a flue gas analyzer. The research shows that the gas products include NOX, O3, CH4, and COX. Through the quantitative analysis, the conversion efficiency of COX increases with the augment of the accumulated transferred charge, and the change law of the CO generation efficiency has an extreme value. With the corresponding calculation and the observation of the scanning electron microscope, it is found that most of the carbon consumed from the graphite electrodes is converted to amorphous elemental carbon, and the insufficiency of the carbon-oxygen reaction leads to the problem of carbon residue, for 20%-45% of elemental carbon is not oxidized. The size of amorphous elemental carbon is about several micrometers to tens micrometers by the analysis of metallographic microscope. In the condition of compressed air, changing the amount of transferred charge is helpful to improve the carbon-oxygen reaction efficiency and inhibit the problem of carbon residue.

  6. Incorporating Charging/Discharging Strategy of Electric Vehicles into Security-Constrained Optimal Power Flow to Support High Renewable Penetration

    Directory of Open Access Journals (Sweden)

    Kyungsung An

    2017-05-01

    Full Text Available This research aims to improve the operational efficiency and security of electric power systems at high renewable penetration by exploiting the envisioned controllability or flexibility of electric vehicles (EVs; EVs interact with the grid through grid-to-vehicle (G2V and vehicle-to-grid (V2G services to ensure reliable and cost-effective grid operation. This research provides a computational framework for this decision-making process. Charging and discharging strategies of EV aggregators are incorporated into a security-constrained optimal power flow (SCOPF problem such that overall energy cost is minimized and operation within acceptable reliability criteria is ensured. Particularly, this SCOPF problem has been formulated for Jeju Island in South Korea, in order to lower carbon emissions toward a zero-carbon island by, for example, integrating large-scale renewable energy and EVs. On top of conventional constraints on the generators and line flows, a unique constraint on the system inertia constant, interpreted as the minimum synchronous generation, is considered to ensure grid security at high renewable penetration. The available energy constraint of the participating EV associated with the state-of-charge (SOC of the battery and market price-responsive behavior of the EV aggregators are also explored. Case studies for the Jeju electric power system in 2030 under various operational scenarios demonstrate the effectiveness of the proposed method and improved operational flexibility via controllable EVs.

  7. Application of HFCT and UHF Sensors in On-Line Partial Discharge Measurements for Insulation Diagnosis of High Voltage Equipment

    Directory of Open Access Journals (Sweden)

    Fernando Álvarez

    2015-03-01

    Full Text Available Partial discharge (PD measurements provide valuable information for assessing the condition of high voltage (HV insulation systems, contributing to their quality assurance. Different PD measuring techniques have been developed in the last years specially designed to perform on-line measurements. Non-conventional PD methods operating in high frequency bands are usually used when this type of tests are carried out. In PD measurements the signal acquisition, the subsequent signal processing and the capability to obtain an accurate diagnosis are conditioned by the selection of a suitable detection technique and by the implementation of effective signal processing tools. This paper proposes an optimized electromagnetic detection method based on the combined use of wideband PD sensors for measurements performed in the HF and UHF frequency ranges, together with the implementation of powerful processing tools. The effectiveness of the measuring techniques proposed is demonstrated through an example, where several PD sources are measured simultaneously in a HV installation consisting of a cable system connected by a plug-in terminal to a gas insulated substation (GIS compartment.

  8. Hospital Ownership of a Postacute Care Facility Influences Discharge Destinations After Emergent Surgery.

    Science.gov (United States)

    Abdelsattar, Zaid M; Gonzalez, Andrew A; Hendren, Samantha; Regenbogen, Scott E; Wong, Sandra L

    2016-08-01

    The aim of the study was to identify hospital characteristics associated with variation in patient disposition after emergent surgery. Colon resections in elderly patients are often done in emergent settings. Although these operations are known to be riskier, there are limited data regarding postoperative discharge destination. We evaluated Medicare beneficiaries who underwent emergent colectomy between 2008 and 2010. Using hierarchical logistic regression, we estimated patient and hospital-level risk-adjusted rates of nonhome discharges. Hospitals were stratified into quintiles based on their nonhome discharge rates. Generalized linear models were used to identify hospital structural characteristics associated with nonhome discharges (comparing discharge to skilled nursing facilities vs home with/without home health services). Of the 122,604 patients surviving to discharge after emergent colectomy at 3012 hospitals, 46.7% were discharged to a nonhome destination. There was a wide variation in risk and reliability-adjusted nonhome discharge rates across hospitals (15% to 80%). Patients at hospitals in the highest quintile of nonhome discharge rates were more likely to have longer hospitalizations (15.1 vs 13.2; P hospital ownership of a skilled nursing facility (P discharges. Nearly half of Medicare beneficiaries are discharged to a nonhome destination after emergent colectomy. Hospital ownership of a skilled nursing facility and low nurse-to-patient ratios are highly associated with nonhome discharges. This may signify the underlying financial incentives to preferentially utilize postacute care facilities under the traditional fee-for-service payment model.

  9. Extremely High Mutation Rate of HIV-1 In Vivo.

    Directory of Open Access Journals (Sweden)

    José M Cuevas

    Full Text Available Rates of spontaneous mutation critically determine the genetic diversity and evolution of RNA viruses. Although these rates have been characterized in vitro and in cell culture models, they have seldom been determined in vivo for human viruses. Here, we use the intrapatient frequency of premature stop codons to quantify the HIV-1 genome-wide rate of spontaneous mutation in DNA sequences from peripheral blood mononuclear cells. This reveals an extremely high mutation rate of (4.1 ± 1.7 × 10-3 per base per cell, the highest reported for any biological entity. Sequencing of plasma-derived sequences yielded a mutation frequency 44 times lower, indicating that a large fraction of viral genomes are lethally mutated and fail to reach plasma. We show that the HIV-1 reverse transcriptase contributes only 2% of mutations, whereas 98% result from editing by host cytidine deaminases of the A3 family. Hypermutated viral sequences are less abundant in patients showing rapid disease progression compared to normal progressors, highlighting the antiviral role of A3 proteins. However, the amount of A3-mediated editing varies broadly, and we find that low-edited sequences are more abundant among rapid progressors, suggesting that suboptimal A3 activity might enhance HIV-1 genetic diversity and pathogenesis.

  10. High monetary reward rates and caloric rewards decrease temporal persistence.

    Science.gov (United States)

    Fung, Bowen J; Bode, Stefan; Murawski, Carsten

    2017-02-22

    Temporal persistence refers to an individual's capacity to wait for future rewards, while forgoing possible alternatives. This requires a trade-off between the potential value of delayed rewards and opportunity costs, and is relevant to many real-world decisions, such as dieting. Theoretical models have previously suggested that high monetary reward rates, or positive energy balance, may result in decreased temporal persistence. In our study, 50 fasted participants engaged in a temporal persistence task, incentivised with monetary rewards. In alternating blocks of this task, rewards were delivered at delays drawn randomly from distributions with either a lower or higher maximum reward rate. During some blocks participants received either a caloric drink or water. We used survival analysis to estimate participants' probability of quitting conditional on the delay distribution and the consumed liquid. Participants had a higher probability of quitting in blocks with the higher reward rate. Furthermore, participants who consumed the caloric drink had a higher probability of quitting than those who consumed water. Our results support the predictions from the theoretical models, and importantly, suggest that both higher monetary reward rates and physiologically relevant rewards can decrease temporal persistence, which is a crucial determinant for survival in many species. © 2017 The Authors.

  11. High rate of adaptive evolution in two widespread European pines.

    Science.gov (United States)

    Grivet, Delphine; Avia, Komlan; Vaattovaara, Aleksia; Eckert, Andrew J; Neale, David B; Savolainen, Outi; González-Martínez, Santiago C

    2017-11-07

    Comparing related organisms with differing ecological requirements and evolutionary histories can shed light on the mechanisms and drivers underlying genetic adaptation. Here, by examining a common set of hundreds of loci, we compare patterns of nucleotide diversity and molecular adaptation of two European conifers (Scots pine and maritime pine) living in contrasted environments and characterized by distinct population genetic structure (low and clinal in Scots pine, high and ecotypic in maritime pine) and demographic histories. We found higher nucleotide diversity in Scots pine than in maritime pine, whereas rates of new adaptive substitutions (ωa ), as estimated from the Distribution of Fitness Effects (DFE), were similar across species, and among the highest found in plants. Sample size and population genetic structure did not appear to have resulted in significant bias in estimates of ωa . Moreover, population contraction-expansion dynamics for each species did not differentially affect differentially the rate of adaptive substitution in these two pines. Several methodological and biological factors may underlie the unusually high rate of adaptive evolution of Scots pine and maritime pine. By providing two new case studies with contrasting evolutionary histories, we contribute to disentangling the multiple factors potentially affecting adaptive evolution in natural plant populations. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  12. Taylor dispersion analysis in coiled capillaries at high flow rates.

    Science.gov (United States)

    Lewandrowska, Anna; Majcher, Aldona; Ochab-Marcinek, Anna; Tabaka, Marcin; Hołyst, Robert

    2013-04-16

    Taylor Dispersion Analysis (TDA) has been performed for analytes moving at high flow rates in long, coiled capillaries. A thin injection zone of the analyte is stretched by the flow and final distribution of concentration of the analyte at the end of the capillary has the gaussian shape. The high flow rates in coiled capillary generate vortices. They convectively mix the analyte across the capillary. This mixing reduces the width of the gaussian distribution several times in comparison to the width obtained in a straight capillary in standard TDA. We have determined an empirical, scaling equation for the width as a function of the flow rate, molecular diffusion coefficient of the analyte, viscosity of the carrier phase, internal radius of the cylindrical capillary, and external radius of the coiled capillary. This equation can be used for different sizes of capillaries in a wide range of parameters without an additional calibration procedure. Our experimental results of flow in the coiled capillary could not be explained by current models based on approximate solutions of the Navier-Stokes equation. We applied the technique to determine the diffusion coefficients of the following analytes: salts, drugs, single amino acids, peptides (from dipeptides to hexapeptides), and proteins.

  13. High Rate Proton Irradiation of 15mm Muon Drifttubes

    CERN Document Server

    INSPIRE-00295941

    2012-01-01

    Future LHC luminosity upgrades will significantly increase the amount of background hits from photons, neutrons and protons in the detectors of the ATLAS muon spectrometer. At the proposed LHC peak luminosity of 5*10^34 1/cm^2s, background hit rates of more than 10 kHz/cm^2 are expected in the innermost forward region, leading to a loss of performance of the current tracking chambers. Based on the ATLAS Monitored Drift Tube chambers, a new high rate capable drift tube detecor using tubes with a reduced diameter of 15mm was developed. To test the response to highly ionizing particles, a prototype chamber of 46 15mm drift tubes was irradiated with a 20 MeV proton beam at the tandem accelerator at the Maier-Leibnitz Laboratory, Munich. Three tubes in a planar layer were irradiated while all other tubes were used for reconstruction of cosmic muon tracks through irradiated and non-irradiated parts of the chamber. To determine the rate capability of the 15mm drift-tubes we investigated the effect of the proton hit ...

  14. Comparable cell survival between high dose rate flattening filter free and conventional dose rate irradiation.

    Science.gov (United States)

    Verbakel, Wilko F A R; van den Berg, Jaap; Slotman, Ben J; Sminia, Peter

    2013-04-01

    Investigation of clonogenic cell survival and cell proliferation following single dose and fractionated delivery of high dose rate flattening filter free (FFF) irradiation compared to conventional dose rates. The human astrocytoma D384, glioma T98 and lung carcinoma SW1573 cell lines were irradiated using either a single dose (0-12 Gy) or a fractionated protocol of 5 daily fractions of 2 Gy (D384) or 3 Gy (SW1573). Cells were irradiated inside a phantom using fixed gantry beams of a linear accelerator. A sliding window technique created homogeneous dose distributions over the surface of the cell cultures. Irradiations using standard beams (6 MV, 600 MU/min.) and high dose rate FFF beams (10 MV, 2400 MU/min.) were compared. Cell survival was determined by clonogenic assay. In the fractionated irradiation set-up, the number of clonogenic cells was estimated by including tumor cell proliferation during the overall treatment time in the analysis. All cell lines showed equal cell survival following irradiation using either the FFF beams or conventional flattened (FF) beams. This was observed after single dose exposure (0-12 Gy) as well as after fractionated irradiation (p = 0.08 for D384 and 0.20 for SW1373 cell lines). FFF irradiation with a dose rate of 2400 MU/min and four times higher dose per pulse compared to irradiation with FF beams did not change cell survival for three human cancer cell lines up to a fraction dose of 12 Gy compared to irradiation using FF beams.

  15. High-strain, high-strain-rate deformation of tantalum and tantalum-tungsten alloys

    OpenAIRE

    Vecchio, K.

    1994-01-01

    Under certain high strain rate conditions, plastic deformation can be assumed to be adiabatic, and a significant temperature increase can occur at large strains. In this study, tantalum and tantalum-tungsten alloys were subjected to high shear strains at high strain rate using a specially-designed stepped specimen in a Hopkinson bar. Upon completion of the deformation, the region is cooled to below one-half of the temperature achieved due to the adiabatic heating in less than one millisecond....

  16. High Rates of Bleeding Complications among Hospitalized Patients with Hereditary Hemorrhagic Telangiectasia in the United States.

    Science.gov (United States)

    Brinjikji, Waleed; Wood, Christopher P; Lanzino, Giuseppe; Cloft, Harry J; Misra, Sanjay; Kallmes, David F; Kamath, Patrick; Pruthi, Rajiv K; Krowka, Michael J; Swanson, Karen L; Iyer, Vivek N

    2016-09-01

    There is sparse published literature on the causes and outcomes of hospitalization of patients with hereditary hemorrhagic telangiectasia (HHT). To evaluate rates of various complications, comorbidities, and in-hospital outcomes of patients with HHT using a large, multihospital inpatient database. We identified patients with HHT in the U.S. Nationwide Inpatient Sample between 2000 and 2012. Rates of hemorrhagic, neurological, hepatic, and cardiopulmonary complications among hospitalized patients with HHT were evaluated. We also studied procedure use rates for blood transfusion, endoscopy, and epistaxis treatment. Hospitalization outcomes, including in-hospital mortality, discharge status, charges, and length of stay, were evaluated. We identified 10,293 patients with HHT. The mean age of the HHT population was 60.7 years. Sixty percent of patients were female. More than 75% of HHT hospitalizations occurred in those older than 50 years of age. Patients with HHT had high rates of bleeding-related complications, including anemia (53.3%), epistaxis (16.2%), and gastrointestinal bleeding (10.8%). Overall, bleeding complications accounted for 62.7% of HHT-related complications. Thirty-eight percent of hospitalized patients with HHT received one or more transfusions of a blood product. Cardiopulmonary complications were present in 41.0% of the cases. Congestive heart failure was the second most common individual complication among patients with HHT, affecting 19.9% of patients. The in-hospital mortality rate was 1.9%. In this large, nationwide study, we found that nearly two-thirds of patients hospitalized with HHT experienced a bleeding-related complication. Nearly 40% of hospitalized patients with HHT required transfusion of blood products. Cardiopulmonary complications, including congestive heart failure, were the second most common complication. The high burden of bleeding-related complications points to a significant unmet clinical need for these patients.

  17. High mortality rates after non-elective colon cancer resection

    DEFF Research Database (Denmark)

    Bakker, I S; Snijders, H S; Grossmann, Irene

    2016-01-01

    AIM: Colon cancer resection in a non-elective setting is associated with high rates of morbidity and mortality. The aim of this retrospective study is to identify risk factors for overall mortality after colon cancer resection with a special focus on non-elective resection. METHOD: Data were...... obtained from the Dutch Surgical Colorectal Audit. Patients undergoing colon cancer resection in the Netherlands between January 2009 and December 2013 were included. Patient, treatment and tumour factors were analyzed in relation to the urgency of surgery. The primary outcome was the thirty day...... postoperative mortality. RESULTS: The study included 30,907 patients. In 5934 (19.2%) of patients, a non-elective colon cancer resection was performed. There was a 4.4% overall mortality rate, with significantly more deaths after non-elective surgery (8.5% vs 3.4%, P

  18. GPU accelerated processing of astronomical high frame-rate videosequences

    Science.gov (United States)

    Vítek, Stanislav; Švihlík, Jan; Krasula, Lukáš; Fliegel, Karel; Páta, Petr

    2015-09-01

    Astronomical instruments located around the world are producing an incredibly large amount of possibly interesting scientific data. Astronomical research is expanding into large and highly sensitive telescopes. Total volume of data rates per night of operations also increases with the quality and resolution of state-of-the-art CCD/CMOS detectors. Since many of the ground-based astronomical experiments are placed in remote locations with limited access to the Internet, it is necessary to solve the problem of the data storage. It mostly means that current data acquistion, processing and analyses algorithm require review. Decision about importance of the data has to be taken in very short time. This work deals with GPU accelerated processing of high frame-rate astronomical video-sequences, mostly originating from experiment MAIA (Meteor Automatic Imager and Analyser), an instrument primarily focused to observing of faint meteoric events with a high time resolution. The instrument with price bellow 2000 euro consists of image intensifier and gigabite ethernet camera running at 61 fps. With resolution better than VGA the system produces up to 2TB of scientifically valuable video data per night. Main goal of the paper is not to optimize any GPU algorithm, but to propose and evaluate parallel GPU algorithms able to process huge amount of video-sequences in order to delete all uninteresting data.

  19. Precise muon drift tube detectors for high background rate conditions

    CERN Document Server

    Engl, Albert; Dünnweber, Wolfgang

    The muon spectrometer of the ATLAS-experiment at the Large H adron Collider consists of drift tube chambers, which provide the precise m easurement of trajec- tories of traversing muons. In order to determine the moment um of the muons with high precision, the measurement of the position of the m uon in a single tube has to be more accurate than σ ≤ 100 m. The large cross section of proton-proton-collisions and th e high luminosity of the accelerator cause relevant background of neutrons and γ s in the muon spectrome- ter. During the next decade a luminosity upgrade [1] to 5 10 34 cm − 2 s − 1 is planned, which will increase the background counting rates consider ably. In this context this work deals with the further development of the existing drift chamber tech- nology to provide the required accuracy of the position meas urement under high background conditions. Two approaches of improving the dri ft tube chambers are described: • In regions of moderate background rates a faster and more lin ear ...

  20. Handling high data rate detectors at Diamond Light Source

    Science.gov (United States)

    Pedersen, U. K.; Rees, N.; Basham, M.; Ferner, F. J. K.

    2013-03-01

    An increasing number of area detectors, in use at Diamond Light Source, produce high rates of data. In order to capture, store and process this data High Performance Computing (HPC) systems have been implemented. This paper will present the architecture and usage for handling high rate data: detector data capture, large volume storage and parallel processing. The EPICS area Detector frame work has been adopted to abstract the detectors for common tasks including live processing, file format and storage. The chosen data format is HDF5 which provides multidimensional data storage and NeXuS compatibility. The storage system and related computing infrastructure include: a centralised Lustre based parallel file system, a dedicated network and a HPC cluster. A well defined roadmap is in place for the evolution of this to meet demand as the requirements and technology advances. For processing the science data the HPC cluster allow efficient parallel computing, on a mixture of ×86 and GPU processing units. The nature of the Lustre storage system in combination with the parallel HDF5 library allow efficient disk I/O during computation jobs. Software developments, which include utilising optimised parallel file reading for a variety of post processing techniques, are being developed in collaboration as part of the Pan-Data EU Project (www.pan-data.eu). These are particularly applicable to tomographic reconstruction and processing of non crystalline diffraction data.

  1. Electronic discharge summaries.

    Science.gov (United States)

    Stetson, Peter D; Keselman, Alla; Rappaport, Daniel; Van Vleck, Tielman; Cooper, Mary; Boyer, Aurelia; Hripcsak, George

    2005-01-01

    Timely completion of Discharge Summaries is a requirement of high quality care. We developed a system for writing electronic Discharge Summaries. DSUM Writer has generated 2464 of 7349 total summaries (34%) and has paid for itself during its first 8 weeks in production. DSUM Writer is a component of a suite of tools (eNote) for electronic physician documentation used to support clinical care, billing and narrative analysis research.

  2. High Rate Laser Pitting Technique for Solar Cell Texturing

    Energy Technology Data Exchange (ETDEWEB)

    Hans J. Herfurth; Henrikki Pantsar

    2013-01-10

    High rate laser pitting technique for solar cell texturing Efficiency of crystalline silicon solar cells can be improved by creating a texture on the surface to increase optical absorption. Different techniques have been developed for texturing, with the current state-of-the-art (SOA) being wet chemical etching. The process has poor optical performance, produces surfaces that are difficult to passivate or contact and is relatively expensive due to the use of hazardous chemicals. This project shall develop an alternative process for texturing mc-Si using laser micromachining. It will have the following features compared to the current SOA texturing process: -Superior optical surfaces for reduced front-surface reflection and enhanced optical absorption in thin mc-Si substrates -Improved surface passivation -More easily integrated into advanced back-contact cell concepts -Reduced use of hazardous chemicals and waste treatment -Similar or lower cost The process is based on laser pitting. The objective is to develop and demonstrate a high rate laser pitting process which will exceed the rate of former laser texturing processes by a factor of ten. The laser and scanning technologies will be demonstrated on a laboratory scale, but will use inherently technologies that can easily be scaled to production rates. The drastic increase in process velocity is required for the process to be implemented as an in-line process in PV manufacturing. The project includes laser process development, development of advanced optical systems for beam manipulation and cell reflectivity and efficiency testing. An improvement of over 0.5% absolute in efficiency is anticipated after laser-based texturing. The surface textures will be characterized optically, and solar cells will be fabricated with the new laser texturing to ensure that the new process is compatible with high-efficiency cell processing. The result will be demonstration of a prototype process that is suitable for scale-up to a

  3. Design of high-bit-rate coherent communication links

    Science.gov (United States)

    Konyshev, V. A.; Leonov, A. V.; Nanii, O. E.; Novikov, A. G.; Treshchikov, V. N.; Ubaydullaev, R. R.

    2016-12-01

    We report an analysis of the problems encountered in the design of modern high-bit-rate coherent communication links. A phenomenological communication link model is described, which is suitable for solving applied tasks of the network design with nonlinear effects taken into account. We propose an engineering approach to the design that is based on the use of fundamental nonlinearity coefficients calculated in advance for the experimental configurations of communication links. An experimental method is presented for calculating the nonlinearity coefficient of communication links. It is shown that the proposed approach allows one to successfully meet the challenges in designing communication networks.

  4. Factors affecting high resting pulse rate in military pilots

    Directory of Open Access Journals (Sweden)

    Minarma Siagian

    2014-02-01

    Aviation and Aerospace (LAKESPRA from 2003 to 2008. The data extracted from medical records were age, rank, total flight hours, average yearly flight hours, and type of aircraft. Results: Out of 539 pilots, there were 155 with high resting pulse rate. Compared to pilots aged 23-29 years, pilots aged 30-39 years had 66% more risk for high resting pulse rate [adjusted odds ratio (ORa = 1.66; 95% confidence interval (CI = 1.17-2.35, P = 0.004], and those aged 40-49 years had a 2.4 risk (ORa = 2.40; P = 0.000]. Compared to pilots of transport planes, jet fighter pilots had a 59% more risk for high resting pulse rate (ORa = 1.59; P = 0.002. Conclusion: Older  age  and  fighter  jets  increased  the  risk  of  high  resting  pulse  rate  in  pilots. (Health Science Indones 2013;2:51-4Key words: age, type of aircraft, resting pulse rate, pilots

  5. Potentiostatic activation of as-made graphene electrodes for high-rate performance in supercapacitors

    Science.gov (United States)

    Senthilkumar, Krishnan; Jeong, Seok; Lah, Myoung Soo; Sohn, Kee-Sun; Pyo, Myoungho

    2016-10-01

    A thermally expanded graphene oxide (EGO) electrode is electrochemically activated to simultaneously introduce electrolyte-accessible mesopores and oxygen functional groups. The former is produced via O2 evolution and the latter is incorporated by the intermediate hydroxyl radicals generated during the potentiostatic oxidation of H2O in 1 M H2SO4 at 1.2 V (vs. Ag/AgCl). When applied as a supercapacitor, the potentiostatically treated EGO (EGO-PS) shows significant enhancement in an electric-double layer (EDL) process with a noticeable Faradaic reaction and delivers high capacitance at fast charge/discharge (C/D) rates (334 F g-1 at 0.1 A g-1 and 230 F g-1 at 50 A g-1). In contrast to EGO-PS, EGO that is oxidized potentiodynamically (EGO-PD) shows negligible enhancement in EDL currents. EGO that is subjected to successive potential pulses also shows behaviors similar to EGO-PD, which indicates the importance of hydroxyl radical accumulation via a potentiostatic method for simultaneous functionalization and microstructural control of graphenes. The potentiostatic post-treatment presented here is a convenient post-treatment strategy that could be used to readily increase capacitance and simultaneously improve the high-rate performance of carbon-based electrodes.

  6. Study on the Application of an Ultra-High-Frequency Fractal Antenna to Partial Discharge Detection in Switchgears

    Directory of Open Access Journals (Sweden)

    Chenguo Yao

    2013-12-01

    Full Text Available The ultra-high-frequency (UHF method is used to analyze the insulation condition of electric equipment by detecting the UHF electromagnetic (EM waves excited by partial discharge (PD. As part of the UHF detection system, the UHF sensor determines the detection system performance in signal extraction and recognition. In this paper, a UHF antenna sensor with the fractal structure for PD detection in switchgears was designed by means of modeling, simulation and optimization. This sensor, with a flat-plate structure, had two resonance frequencies of 583 MHz and 732 MHz. In the laboratory, four kinds of insulation defect models were positioned in the testing switchgear for typical PD tests. The results show that the sensor could reproduce the electromagnetic waves well. Furthermore, to optimize the installation position of the inner sensor for achieving best detection performance, the precise simulation model of switchgear was developed to study the propagation characteristics of UHF signals in switchgear by finite-difference time-domain (FDTD method. According to the results of simulation and verification test, the sensor should be positioned at the right side of bottom plate in the front cabinet. This research established the foundation for the further study on the application of UHF technique in switchgear PD online detection.

  7. Influence of the location and type of epileptogenic lesion on scalp interictal epileptiform discharges and high-frequency oscillations.

    Science.gov (United States)

    Cuello-Oderiz, Carolina; von Ellenrieder, Nicolas; Dubeau, François; Gotman, Jean

    2017-12-01

    To increase the diagnostic power of scalp electroencephalography (EEG) by investigating whether lesion type and location influence the morphology of interictal epileptic discharges (IEDs) and the likelihood that IEDs and high-frequency oscillations (HFOs) are present. We studied EEG activity in epilepsy patients with lesional epilepsy. Lesions were classified by type and by location (region and depth). We marked a maximum of 50 IEDs during deep non-rapid eye movement sleep. IEDs were identified as spikes or sharp waves with or without slow waves, or bursts of spikes or sharp waves with or without slow waves. We analyzed HFOs in the studies showing at least 50 IEDs. In 192 scalp EEG studies, the differences in the percentage of studies showing IEDs in each depth-related group were not statistically significant, whereas HFOs (55 studies) predominated in patients exhibiting superficial lesions (pinfluence the presence of IEDs, as one might expect, but it influences that of HFOs. This is explained as follows. HFOs are generated in the epileptogenic region, do not propagate, and hence are only visible on scalp EEG with superficial lesions. IEDs can result from a nearby focus or propagate from a deep generator and are therefore equally present with deep, intermediate, and superficial lesions. Additionally, IED morphology provides information in determining the lesion type. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

  8. Probabilistic analysis for the response of nonlinear base isolation system under the ground excitation induced by high dam flood discharge

    Science.gov (United States)

    Liang, Chao; Zhang, Jinliang; Lian, Jijian; Liu, Fang; Li, Xinyao

    2017-10-01

    According to theoretical analysis, a general characteristic of the ground vibration induced by high dam flood discharge is that the dominant frequency ranges over several narrow frequency bands, which is verified by observations from the Xiangjiaba Hydropower Station. Nonlinear base isolation is used to reduce the structure vibration under ground excitation and the advantage of the isolation application is that the low-frequency resonance problem does not need to be considered due to its excitation characteristics, which significantly facilitate the isolation design. In order to obtain the response probabilistic distribution of a nonlinear system, the state space split technique is modified. As only a few degrees of freedom are subjected to the random noise, the probabilistic distribution of the response without involving stochastic excitation is represented by the δ function. Then, the sampling property of the δ function is employed to reduce the dimension of the Fokker-Planck- Kolmogorov (FPK) equation and the low-dimensional FPK equation is solvable with existing methods. Numerical results indicate that the proposed approach is effective and accurate. Moreover, the response probabilistic distributions are more reasonable and scientific than the peak responses calculated by conventional time and frequency domain methods.

  9. River Flow Regimes and Effective Discharge

    Science.gov (United States)

    Basso, S.; Sprocati, R.; Frascati, A.; Marani, M.; Schirmer, M.; Botter, G.

    2015-12-01

    The concept of effective discharge is widespread in geomorphology and river engineering and restoration. For example, it is used to design the most stable channel configuration, to estimate sedimentation rate and lifespan of reservoirs and to characterize the hydrologic forcing in models studying long-term evolution of rivers. Accordingly, the effective discharge has been the focus of countless empirical, theoretical and numerical studies, which found it to vary among catchments as a function of climate, landscape and river morphology, type of transport (dissolved, suspended or bedload), and of streamflow variability. The heterogeneity of the effective discharge values observed in different catchments challenges a thorough understanding of its pivotal drivers, and a consistent framework which explains observations carried out in different geographic areas is still lacking. In the present work, the observed diversity is explained in terms of the underlying heterogeneity of river flow regimes, by linking effective discharge to attributes of the sediment rating curve and to streamflow variability, as resulting from climatic and landscape drivers. An analytic expression of the effective ratio (i.e. the ratio between effective discharge and mean streamflow) is provided, which captures observed values of effective discharge for suspended sediment transport in a set of catchments of the continental United States. The framework disentangles hydrologic and landscape controls on effective discharge, and highlights distinct effective ratios of persistent and erratic hydrologic regimes (respectively characterized by low and high flow variability), attributable to intrinsically different streamflow dynamics. Clusters of river catchments characterized by similar streamflow dynamics can be identified. The framework provides an opportunity for first-order estimates of effective discharge in rivers belonging to different areas, based on the type of flow regime.

  10. On the response of rubbers at high strain rates.

    Energy Technology Data Exchange (ETDEWEB)

    Niemczura, Johnathan Greenberg (University of Texas-Austin)

    2010-02-01

    In this report, we examine the propagation of tensile waves of finite deformation in rubbers through experiments and analysis. Attention is focused on the propagation of one-dimensional dispersive and shock waves in strips of latex and nitrile rubber. Tensile wave propagation experiments were conducted at high strain-rates by holding one end fixed and displacing the other end at a constant velocity. A high-speed video camera was used to monitor the motion and to determine the evolution of strain and particle velocity in the rubber strips. Analysis of the response through the theory of finite waves and quantitative matching between the experimental observations and analytical predictions was used to determine an appropriate instantaneous elastic response for the rubbers. This analysis also yields the tensile shock adiabat for rubber. Dispersive waves as well as shock waves are also observed in free-retraction experiments; these are used to quantify hysteretic effects in rubber.

  11. New Approach to reduce High School Dropout Rates

    Directory of Open Access Journals (Sweden)

    Mauricio Cristhian Portillo-Torres

    2015-05-01

    Full Text Available From 2006 to 2014, the Ministry of Public Education of Costa Rica implemented four strategic actions to reduce high school dropout rates. The main purpose of these actions was to promote student participation and student identification with their school. Studies prepared by the Ministry of Education and the Comptroller of the Republic were revised to assess the impact of these actions. The result of these actions does not show an actual decrease in the number of students who leave high school. Therefore, a more holistic view is necessary to ensure the students’ stay. This review suggests using use the concept of student engagement and applying a three tier system-wide dropout preventive actions: universal, targeted and intensive.

  12. Automated Production of High Rep Rate Foam Targets

    Science.gov (United States)

    Hall, F.; Spindloe, C.; Haddock, D.; Tolley, M.; Nazarov, W.

    2016-04-01

    Manufacturing low density targets in the numbers needed for high rep rate experiments is highly challenging. This report summarises advances from manual production to semiautomated and the improvements that follow both in terms of production time and target uniformity. The production process is described and shown to be improved by the integration of an xyz robot with dispensing capabilities. Results are obtained from manual and semiautomated production runs and compared. The variance in the foam thickness is reduced significantly which should decrease experimental variation due to target parameters and could allow for whole batches to be characterised by the measurement of a few samples. The work applies to both foil backed and free standing foam targets.

  13. Resistance of the boreal forest to high burn rates.

    Science.gov (United States)

    Héon, Jessie; Arseneault, Dominique; Parisien, Marc-André

    2014-09-23

    Boreal ecosystems and their large carbon stocks are strongly shaped by extensive wildfires. Coupling climate projections with records of area burned during the last 3 decades across the North American boreal zone suggests that area burned will increase by 30-500% by the end of the 21st century, with a cascading effect on ecosystem dynamics and on the boreal carbon balance. Fire size and the frequency of large-fire years are both expected to increase. However, how fire size and time since previous fire will influence future burn rates is poorly understood, mostly because of incomplete records of past fire overlaps. Here, we reconstruct the length of overlapping fires along a 190-km-long transect during the last 200 y in one of the most fire-prone boreal regions of North America to document how fire size and time since previous fire will influence future fire recurrence. We provide direct field evidence that extreme burn rates can be sustained by a few occasional droughts triggering immense fires. However, we also show that the most fire-prone areas of the North American boreal forest are resistant to high burn rates because of overabundant young forest stands, thereby creating a fuel-mediated negative feedback on fire activity. These findings will help refine projections of fire effect on boreal ecosystems and their large carbon stocks.

  14. Spall fracture in aluminium alloy at high strain rates

    Science.gov (United States)

    Joshi, K. D.; Rav, Amit; Sur, Amit; Kaushik, T. C.; Gupta, Satish C.

    2016-05-01

    Spall fracture strength and dynamic yield strength has been measured in 8mm thick target plates of aluminium alloy Al2024-T4 at high strain rates generated in three plate impact experiments carried out at impact velocities of 180 m/s, 370 m/s and 560m/s, respectively, using single stage gas gun facility. In each experiment, the free surface velocity history of the Al2024-T4 sample plate measured employing velocity interferometer system for any reflector (VISAR) is used to determine the spall strength and dynamic yield strength of this material. The spall strength of 1.11 GPa, 1.16 GPa and 1.43 GPa, determined from measured free surface velocity history of sample material in three experiments performed at impact velocity of 180 m/s, 370 m/s and 560 m/s, respectively, are higher than the quasi static value of 0.469 GPa and display almost linearly increasing trend with increasing impact velocity or equivalently with increasing strain rates. The average strain rates just ahead of the spall fracture are determined to be 1.9×10 4/s, 2.0×104/s and 2.5×104/s, respectively. The dynamic yield strength determined in the three experiments range from 0.383 GPa to 0.407 GPa, which is higher than the quasi static value of 0.324GPa.

  15. On the Static Accuracy of Charge-Discharge Units Intended for Electrical Tests of High Capacity Li-ion Batteries

    Science.gov (United States)

    Mizrah, E. A.; Lobanov, D. K.; Kopylov, E. A.; Balakirev, R. V.; Fedchenko, A. S.

    2017-10-01

    Performing of the cycle testing according to the principles of Dynamic Stress Test can significantly reduce the overall time of development and production of batteries, which in turn allows reducing the cost of designing and testing of the spacecraft power systems. Performing of Dynamic Stress Test require special charge-discharge units that allows to perform a full cycle of electrical tests of batteries, including cyclic testing. Providing the required accuracy of measurement and stabilization of certain attributes of Li-ion battery operating modes is one of the problems that arise during thedevelopment of such charge-discharge units. The following attributes are of particular interest: charge and discharge currents, discharge powers, battery voltages. Analysis of the charge-discharge unit as a control system allows evaluating the steady-state stabilization error of the required attributes of the developed device. Moreover, using a digital integrator in the control system of the charge-discharge unit allows providing specified values of steady-state stabilization error of required attributes in different test modes.

  16. STUDY OF HIGH RATE SEDIMENTATION TANK IN WATER TREATMENT PLANTS

    Directory of Open Access Journals (Sweden)

    M.R SHA MANSOURI

    2001-06-01

    Full Text Available Introduction: Sedimentation is considered as an important process in removing turbidity produced in water and wastewater plants. Gravity sedimentation is usually the first method considered in water treatment system. However, required overflow rates (OFRs to remove turbidity in the conventional clarifiers are too low. Therefore, the shallow depth sedimentation concept was studied remove turbidity in order to increase OFRs of gravity setting equipment. Methods: Using a pilot with parallel plates with effect area 1.5 m2 and 1.5 m depth. The independent parameters such as OFRs, sludge concentration and turbidity were evaluated for turbidity removal. The pilot is located in Isfahan Water Treatment Plant. Results: The efficacy of pilot for turbidity 10-50 NTU is equal to 50 percent (P<0.01. The maximum removal efficiency at sludge concentration 270 ml/lit was obtained (P<0.01. A nonlinear relationship exists between removal efficiency (TR%, sludge concentration (Sc over flowrates (OFR and influent turbidity (Tu in pilot. Discussion: By using high rate sedimentation tank in water treatment plant, detection time reduced from 3 hours to 20-30 minute, turbidity removal increased up to 30 percent in compare with conventional sedimentation. Also, it has economic benefits and high efficiency.

  17. Dose determination in high dose-rate brachytherapy.

    Science.gov (United States)

    Houdek, P V; Schwade, J G; Wu, X; Pisciotta, V; Fiedler, J A; Serago, C F; Markoe, A M; Abitbol, A A; Lewin, A A; Braunschweiger, P G

    1992-01-01

    Although high dose-rate brachytherapy with a single, rapidly moving radiation source is becoming a common treatment modality, a suitable formalism for determination of the dose delivered by a moving radiation source has not yet been developed. At present, brachytherapy software simulates high dose-rate treatments using only a series of stationary sources, and consequently fails to account for the dose component delivered while the source is in motion. We now describe a practical model for determination of the true, total dose administered. The algorithm calculates both the dose delivered while the source is in motion within and outside of the implanted volume (dynamic component), and the dose delivered while the source is stationary at a series of fixed dwell points. It is shown that the dynamic dose element cannot be ignored because it always increases the dose at the prescription points and, in addition, distorts the dose distribution within and outside of the irradiated volume. Failure to account for the dynamic dose component results in dosimetric errors that range from significant (> 10%) to negligible (source activity, and source speed as defined by the implant geometry.

  18. High-rep-rate Thomson scattering for LHD

    Science.gov (United States)

    den Hartog, D. J.; Borchardt, M. T.; Holly, D. J.; Schmitz, O.; Yasuhara, R.; Yamada, I.; Funaba, H.; Osakabe, M.; Morisaki, T.

    2017-10-01

    A high-rep-rate pulse-burst laser system is being built for the LHD Thomson scattering (TS) diagnostic. This laser will have two operating scenarios, a fast-burst sequence of 15 kHz rep rate for at least 15 ms, and a slow-burst sequence of 1 kHz for at least 50 ms. There will be substantial flexibility in burst sequences for tailoring to experimental requirements. This new laser system will operate alongside the existing lasers in the LHD TS diagnostic, and will use the same beamline. This increase in temporal resolution capability complements the high spatial resolution (144 points) of the LHD TS diagnostic, providing unique measurement capability unmatched on any other fusion experiment. The new pulse-burst laser is a straightforward application of technology developed at UW-Madison, consisting of a Nd:YAG laser head with modular flashlamp drive units and a customized control system. Variable pulse-width drive of the flashlamps is accomplished by IGBT (insulated gate bipolar transistor) switching of electrolytic capacitor banks. Direct control of the laser Pockels cell drive enables optimal pulse energy extraction, producing >1.5 J q-switched pulses with 20 ns FWHM. Burst operation of this laser system will be used to capture fast time evolution of the electron temperature and density profiles during events such as ELMs, RMP perturbations, and various MHD modes. This work is supported by the U. S. Department of Energy and the National Institute for Fusion Science (Japan).

  19. High-temperature rate constant measurements for OH+xylenes

    KAUST Repository

    Elwardani, Ahmed Elsaid

    2015-06-01

    The overall rate constants for the reactions of hydroxyl (OH) radicals with o-xylene (k 1), m-xylene (k 2), and p-xylene (k 3) were measured behind reflected shock waves over 890-1406K at pressures of 1.3-1.8atm using OH laser absorption near 306.7nm. Measurements were performed under pseudo-first-order conditions. The measured rate constants, inferred using a mechanism-fitting approach, can be expressed in Arrhenius form as:k1=2.93×1013exp(-1350.3/T)cm3mol-1s-1(890-1406K)k2=3.49×1013exp(-1449.3/T)cm3mol-1s-1(906-1391K)k3=3.5×1013exp(-1407.5/T)cm3mol-1s-1(908-1383K)This paper presents, to our knowledge, first high-temperature measurements of the rate constants of the reactions of xylene isomers with OH radicals. Low-temperature rate-constant measurements by Nicovich et al. (1981) were combined with the measurements in this study to obtain the following Arrhenius expressions, which are applicable over a wider temperature range:k1=2.64×1013exp(-1181.5/T)cm3mol-1s-1(508-1406K)k2=3.05×109exp(-400/T)cm3mol-1s-1(508-1391K)k3=3.0×109exp(-440/T)cm3mol-1s-1(526-1383K) © 2015 The Combustion Institute.

  20. High energy high rate pulsed power processing of materials by powder consolidation and by railgun deposition

    Science.gov (United States)

    Persad, C.; Marcus, H. L.; Weldon, W. F.

    1987-03-01

    This exploratory research program was initiated to investigate the potential of using pulse power sources for powder consolidation, deposition and other High Energy High Rate Processing. The characteristics of the High Energy High Rate (1MJ/s) powder consolidation using megampere current pulses from a Homopolar Generator, have been defined. Molybdenum Alloy TZM, A Nickel based metallic glass, Copper graphite composites, and P/M Aluminum Alloy X7091 have been investigated. The powder consolidation process produced high densification rates. Density values of 80% to 99% could be obtained with sub second high temperature exposure. Specific energy input and applied pressure were controlling process parameters. Time Temperature Transformation (TTT) concepts underpin a fundamental understanding of pulsed power processing. Deposition experiments were conducted using an exploding foil device (EFD) providing an armature feed to railgun mounted in a vacuum chamber. The material to be deposited - in plasma, gas, liquid or solid state - was accelerated electromagnetically in the railgun and deposited on a substrate.