WorldWideScience

Sample records for ion yield variations

  1. Transient effects in SIMS analysis of Si with Cs sup + at high incidence angles Secondary ion yield variations

    CERN Document Server

    Heide, P A W

    2002-01-01

    Secondary ion mass spectrometry (SIMS) depth profile analysis of Si wafers using 1 keV Cs sup + primary ions at large incidence angles (80 deg. ) is plagued by unusually strong transient effects (variations in both sputter and ion yields). Analysis of a native oxide terminated Si wafer with and without the aid of an O sub 2 leak, and an Ar sup + pre-sputtered wafer revealed correlations between the implanted Cs content and various secondary ion intensities consistent with that expected from a resonance charge transfer process (that assumed by the electron tunneling model). Cs concentrations were defined through X-ray photoelectron spectroscopy of the sputtered surface from SIMS profiles terminated within the transient region. These scaled with the surface roughening occurring under these conditions and can be explained as resulting from the associated drop in sputter rates. An O induced transient effect from the native oxide was also identified. Characterization of these effects allowed the reconstruction of ...

  2. Variation in yield ratios of fragment ions and of ion-pairs from CF2Cl2 following monochromatic soft X-ray absorption

    International Nuclear Information System (INIS)

    Suzuki, I.H.; Saito, N.; Bozek, J.D.

    1995-01-01

    Fragment ions produced from CF 2 Cl 2 have been measured from 44 to 1200eV using a time-of-flight mass spectrometer and monochromatized synchrotron radiation. Positively charged ion pairs from this molecule were observed in the inner-shell excitation regions using a Selected photoion-photoion coincidence technique. Obtained yield ratios of fragment ions indicate that the atomic chlorine ion, Cl + , has the greatest intensity at all photon energies above 60eV and exhibits a steep increase at the Cl L 2,3 -edges. Some fragment ions, in particular CF 2 + , have a clear intensity increase at the transitions of inner-shell electrons to unoccupied molecular orbitals. The ion pair F + - Cl + exhibits the highest yield at most photon energies, and some of the branching ratios for ion-pair production changed significantly near the Cl L 2,3 -edges. (author)

  3. Improving Aspergillus niger tannase yield by N+ ion beam implantation

    Directory of Open Access Journals (Sweden)

    Wei Jin

    2013-02-01

    Full Text Available This work aimed to improve tannase yield of Aspergillus niger through N+ ion beam implantation in submerged fermentation. The energy and dose of N+ ion beam implantation were investigated. The results indicated that an excellent mutant was obtained through nine successive implantations under the conditions of 10 keV and 30-40 (×2.6×10(13 ions/cm², and its tannase yield reached 38.5 U/mL, which was about five-time higher than the original strain. The study on the genetic stability of the mutant showed that its promising performance in tannase production could be stable. The studies of metal ions and surfactants affecting tannase yield indicated that manganese ions, stannum ions, xylene and SDS contained in the culture medium had positive effects on tannase production under submerged fermentation. Magnesium ions, in particular, could enhance the tannase yield by the mutant increasing by 42%, i.e. 53.6 U/mL. Accordingly, low-energy ion implantation could be a desirable approach to improve the fungal tannase yield for its commercial application.

  4. Variational formulation based analysis on growth of yield front in ...

    African Journals Online (AJOL)

    The present study investigates the growth of elastic-plastic front in rotating solid disks of non-uniform thickness having exponential and parabolic geometry variation. The problem is solved through an extension of a variational method in elastoplastic regime. The formulation is based on von-Mises yield criterion and linear ...

  5. Parametric variations of ion transport in TFTR

    International Nuclear Information System (INIS)

    Scott, S.D.; Ernst, D.

    1993-01-01

    This paper is divided into three roughly independent sections. The first is a historical review of the twenty year history of experimental ion heat transport measurements from many tokamaks. The second is a study of ion heat transport in Ohmic TFTR plasmas which shows that χi ∼ χe ∼ 15χi neo . Thus, ion heat transport is demonstrated to be strongly anomalous even the absence of auxiliary heating. The third section describes the variation of χi with local ion temperature in TFTR during auxiliary heating, with emphasis on characterizing the differecens between transport in the L-mode and supershot regimes. The results are consistent with the conjecture that improved ion energy confinement in supershot plasmas is caused by a high ratio of T 1 /T e

  6. Genotype variation in grain yield response to basal N fertilizer ...

    African Journals Online (AJOL)

    user

    2012-07-24

    Jul 24, 2012 ... identify the variation of grain yield response to basal fertilizer among 199 rice varieties with different genetic background, and finally choose the suitable rice varieties for us to ... proper timing, rate, placement, and use of modified forms ... sowed in seedling-bed with uniform nutritional conditions until 3-leaf.

  7. Parameterization of ion channeling half-angles and minimum yields

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, Barney L.

    2016-03-15

    A MS Excel program has been written that calculates ion channeling half-angles and minimum yields in cubic bcc, fcc and diamond lattice crystals. All of the tables and graphs in the three Ion Beam Analysis Handbooks that previously had to be manually looked up and read from were programed into Excel in handy lookup tables, or parameterized, for the case of the graphs, using rather simple exponential functions with different power functions of the arguments. The program then offers an extremely convenient way to calculate axial and planar half-angles, minimum yields, effects on half-angles and minimum yields of amorphous overlayers. The program can calculate these half-angles and minimum yields for 〈u v w〉 axes and [h k l] planes up to (5 5 5). The program is open source and available at (http://www.sandia.gov/pcnsc/departments/iba/ibatable.html).

  8. Increasing crop diversity mitigates weather variations and improves yield stability.

    Science.gov (United States)

    Gaudin, Amélie C M; Tolhurst, Tor N; Ker, Alan P; Janovicek, Ken; Tortora, Cristina; Martin, Ralph C; Deen, William

    2015-01-01

    Cropping sequence diversification provides a systems approach to reduce yield variations and improve resilience to multiple environmental stresses. Yield advantages of more diverse crop rotations and their synergistic effects with reduced tillage are well documented, but few studies have quantified the impact of these management practices on yields and their stability when soil moisture is limiting or in excess. Using yield and weather data obtained from a 31-year long term rotation and tillage trial in Ontario, we tested whether crop rotation diversity is associated with greater yield stability when abnormal weather conditions occur. We used parametric and non-parametric approaches to quantify the impact of rotation diversity (monocrop, 2-crops, 3-crops without or with one or two legume cover crops) and tillage (conventional or reduced tillage) on yield probabilities and the benefits of crop diversity under different soil moisture and temperature scenarios. Although the magnitude of rotation benefits varied with crops, weather patterns and tillage, yield stability significantly increased when corn and soybean were integrated into more diverse rotations. Introducing small grains into short corn-soybean rotation was enough to provide substantial benefits on long-term soybean yields and their stability while the effects on corn were mostly associated with the temporal niche provided by small grains for underseeded red clover or alfalfa. Crop diversification strategies increased the probability of harnessing favorable growing conditions while decreasing the risk of crop failure. In hot and dry years, diversification of corn-soybean rotations and reduced tillage increased yield by 7% and 22% for corn and soybean respectively. Given the additional advantages associated with cropping system diversification, such a strategy provides a more comprehensive approach to lowering yield variability and improving the resilience of cropping systems to multiple environmental

  9. Comparison of secondary ion emission yields for poly-tyrosine between cluster and heavy ion impacts

    International Nuclear Information System (INIS)

    Hirata, K.; Saitoh, Y.; Chiba, A.; Yamada, K.; Takahashi, Y.; Narumi, K.

    2010-01-01

    Emission yields of secondary ions necessary for the identification of poly-tyrosine were compared for incident ion impacts of energetic cluster ions (0.8 MeV C 8 + , 2.4 MeV C 8 + , and 4.0 MeV C 8 + ) and swift heavy monoatomic molybdenum ions (4.0 MeV Mo + and 14 MeV Mo 4+ ) with similar mass to that of the cluster by time-of-flight secondary ion mass analysis combined with secondary ion electric current measurements. The comparison revealed that (1) secondary ion emission yields per C 8 + impact increase with increasing incident energy within the energy range examined, (2) the 4.0 MeV C 8 + impact provides higher emission yields than the impact of the monoatomic Mo ion with the same incident energy (4.0 MeV Mo + ), and (3) the 2.4 MeV C 8 + impact exhibits comparable emission yields to that for the Mo ion impact with higher incident energy (14 MeV Mo 4+ ). Energetic cluster ion impacts effectively produce the characteristic secondary ions for poly-tyrosine, which is advantageous for highly sensitive amino acid detection in proteins using time-of-flight secondary ion mass analysis.

  10. Free-ion yield for tetramethylsilane and tetramethylgermanium

    International Nuclear Information System (INIS)

    Hoshi, Y.; Higuchi, M.; Iso, H.; Sakamoto, M.; Ooyama, K.; Kikuchi, R.; Miyano, K.

    1993-01-01

    In high energy physics experiments, calorimeters are used to measure the total energy dissipated by the primary particles produced from high energy collisions. In one type of calorimeter, ionization chambers filled with liquid argon are used. The necessity of a cryostat in many cases prevents a compact chamber design. Hence, it is very desirable to have liquid ionization chambers operating at room temperature. From this view point, hydrocarbon liquids are intensively investigated as calorimeter media in high energy physics experiments. TMS and TMG are promising liquid materials because they have the properties of a large electron drift velocity and a large free-ion yield. The free-ion yield determines the sensitivity of the chamber and amplifier system to ionizing particles. Here, free-ion yields from 207 Bi conversion electrons were measured as a function of applied electric field in an ionization chamber filled with tetramethylsilane (TMS) or tetramethylgermanium (TMG), which were purified by simple methods. Also, the mean thermalization length of electrons liberated in the liquid was calculated by fitting a Gaussian form for the distribution function. The total free-ion yield and thermalization length in TMS and TMG were obtained to be 3.1 ± 0.3, 3.5 ± 0.2 and 191 ± 12 angstrom, respectively, including the impurity effect in liquid

  11. Diagnostics and equipment for ion temperatures and implosion neutron yields

    International Nuclear Information System (INIS)

    Chen Jiabin; Zheng Zhijian; Peng Hansheng; Wen Shuhuai; Zhang Baohan; Ding Yongkun; Qi Lanying; Chen Ming; Li Chaoguang

    2001-01-01

    Fuel ion temperature is of great importance in the ICF research field. A set of ultra-fast quenched plastic scintillation detector system was fabricated for low yield neutron diagnostic. The detection efficiency and the sensitivity to DT neutrons were scaled using a K-400 accelerator and a pulse neutron tube from Russia with a width 5 - 10 ns, respectively. Its time response functions were calibrated by cosmic ray and implosion neutron separately. Under the conditions of low laser energy so low neutron yield and very limited space, fuel ion temperatures (including implosion neutron yields at the same time) were obtained. The measured ion temperatures for exploding pusher capsules were between 4 keV and 5 keV with errors +-(15 - 25)%. The neutron yields were 5 x 10 8 - 3 x 10 9 for exploding pusher capsules and 1.6 x 10 7 - 3.9 x 10 8 for ablation ones with errors +- (7 - 10)%. Of the six shots of neutron yields calculated, five are in good agreement with authors' experimental results in the range of +- 20%. Not only the heat-conducting mechanism and the effects on implosion of the energy balance of each path of incidence laser, target design, fuel mixture as well as hot electron behavior have been investigated, but also the upgrade level of the laser facility Shengguang II has been tested

  12. Measurements of sputtering yields for low-energy plasma ions

    International Nuclear Information System (INIS)

    Nishi, M.; Yamada, M.; Suckewer, S.; Rosengaus, E.

    1979-04-01

    Sputtering yields of various wall/limiter materials of fusion devices have been extensively measured in the relevant plasma environment for low-energy light ions (E 14 cm -3 and electron temperature up to 10eV. Target materials used were C (graphite), Ti, Mo, Ta, W, and Fe (stainless steel). In order to study the dependence of the sputtering yields on the incident energy of ions, the target samples were held at negative bias voltage up to 300V. The sputtering yields were determined by a weight-loss method and by spectral line intensity measurements. The data obtained in the present experiment agree well with those previously obtained at the higher energies (E greater than or equal to 200eV) by other authors using different schemes; the present data also extend to substantially lower energies (E approx. > 30eV) than hitherto

  13. Locational variation in green fodder yield, dry matter yield, and forage quality of sorghum

    International Nuclear Information System (INIS)

    Hussain, A.; Khan, S.; Mohammad, D.

    2007-01-01

    The present study was designed to find out the variations in for- age yield and quality of sorghum as affected by different environments. The three agroecological zones viz., Agricultural Research Institute (ARI), Sariab, Quetta, Ayub Agricultural Research Institute (AARI), Faisalabad and National Agricultural Research Centre (NARC), Islamabad were selected on the basis of different physiography, geology, temperature, and climate and water availability. Crude protein contents, varied from 6.98 to 8.02 percent, crude fibre contents from 30.84 to 31.68 percent, green fodder yield from 38.91 to 50.64 t/ha and dry matter yield from 8.92 to 10.17 t/ha at the three diverse locations. Maximum crude protein and crude fibre contents were obtained at NARC, Islamabad and AARI, Faisalabad. Maximum green fodder and dry matter yields were also observed at NARC, Islamabad and AARI, Faisalabad. It was also noted that the same genotypes showed differential response when planted under the diverse environments for green fodder yield, dry matter yield, crude protein and crude fibre contents. Therefore, it was concluded that these differences in forage yield and quality traits under diverse environments were due to differences in soil types, soil fertility, temperature, rain- fall and other climatic conditions. (author)

  14. Fully stripped heavy ion yield vs energy for Xe and Au ions

    International Nuclear Information System (INIS)

    Thieberger, P.; Wegner, H.E.; Alonzo, J.; Gould, H.; Anholt, R.E.; Meyerhof, W.E.

    1985-01-01

    The Bevalac is now capable of accelerating U-238 ions to approximately 1 GeV/amu and measurements have shown that fully stripped U-238 ions are produced with good yield at these energies. However, knowing the stripping yields at different energies for U-238 does not allow an accurate prediction for other, lower Z projectiles. Consequently, extensive stripping yield measurements were made for Au-197 and Xe-139 ions. In addition to the stripping measurements from the direct Bevalac beam, pickup measurements were also made with specially prepared bare, one electron, and two electron ions. Since many research groups are considering heavy ion storage rings and/or synchrotrons, the pickup cross section for bare ions is important to estimate beam lifetime in terms of the average machine vacuum. Since the Mylar target provides a pickup probability similar to air, a preliminary analysis of the Xe 54+ and U 92+ data are presented along with predictions for other ions ranging down to Fe 26+ . 11 refs., 3 figs., 1 tab

  15. Fully stripped heavy ion yield vs energy for Xe and Au ions

    Energy Technology Data Exchange (ETDEWEB)

    Thieberger, P.; Wegner, H.E.; Alonzo, J.; Gould, H.; Anholt, R.E.; Meyerhof, W.E.

    1985-01-01

    The Bevalac is now capable of accelerating U-238 ions to approximately 1 GeV/amu and measurements have shown that fully stripped U-238 ions are produced with good yield at these energies. However, knowing the stripping yields at different energies for U-238 does not allow an accurate prediction for other, lower Z projectiles. Consequently, extensive stripping yield measurements were made for Au-197 and Xe-139 ions. In addition to the stripping measurements from the direct Bevalac beam, pickup measurements were also made with specially prepared bare, one electron, and two electron ions. Since many research groups are considering heavy ion storage rings and/or synchrotrons, the pickup cross section for bare ions is important to estimate beam lifetime in terms of the average machine vacuum. Since the Mylar target provides a pickup probability similar to air, a preliminary analysis of the Xe/sup 54 +/ and U/sup 92 +/ data are presented along with predictions for other ions ranging down to Fe/sup 26 +/. 11 refs., 3 figs., 1 tab.

  16. Variational formulation based analysis on growth of yield front in ...

    African Journals Online (AJOL)

    user

    The analysis of rotating disk behavior has been of great interest to many ... strain hardening using Tresca's yield condition and its associated flow rule ...... Determination of Stresses in Gas-Turbine Disks Subjected to Plastic Flow and Creep.

  17. Unused natural variation can lift yield barriers in plant breeding.

    Directory of Open Access Journals (Sweden)

    Amit Gur

    2004-10-01

    Full Text Available Natural biodiversity is an underexploited sustainable resource that can enrich the genetic basis of cultivated plants with novel alleles that improve productivity and adaptation. We evaluated the progress in breeding for increased tomato (Solanum lycopersicum yield using genotypes carrying a pyramid of three independent yield-promoting genomic regions introduced from the drought-tolerant green-fruited wild species Solanum pennellii. Yield of hybrids parented by the pyramided genotypes was more than 50% higher than that of a control market leader variety under both wet and dry field conditions that received 10% of the irrigation water. This demonstration of the breaking of agricultural yield barriers provides the rationale for implementing similar strategies for other agricultural organisms that are important for global food security.

  18. Coincidence of variation in yield and climate in Europe

    DEFF Research Database (Denmark)

    Peltonen-Sainio, P; Jauhiainen, L; Trnka, M

    2010-01-01

    countries (total of 25 regions). Crops studied were spring and winter barley and wheat, winter oilseed rape, potato and sugar beet. Relative yield deviations were determined for all crops. Meteorological data on monthly means for temperature variables, solar radiation, accumulated precipitation...

  19. Winter and spring variation in daily milk yield and mineral ...

    African Journals Online (AJOL)

    201007395

    2013-06-02

    Jun 2, 2013 ... Jersey, Friesian cows and their crosses under a pasture-based dairy system. C.T.W. Nantapo & V. Muchenje ... and mineral composition of pasture-based dairy cows. This was done by ..... Genetic and nongenetic variation in ...

  20. Heavy-ion induced desorption yields of cryogenic surfaces bombarded with 4.2 MeV/u lead ions

    CERN Document Server

    Mahner, E; Evans, L; Kollmus, H; Küchler, D; Scrivens, R; Severin, D; Wengenroth, M; CERN. Geneva. ATS Department

    2011-01-01

    The ion-induced desorption experiment, installed in the CERN Heavy-Ion Accelerator LINAC 3, has been used to study the dynamic outgassing of cryogenic surfaces. Two different targets, bare and goldcoated copper, were bombarded under perpendicular impact with 4.2 MeV/u Pb54+ ions. Partial pressure rises of H2, CH4, CO, and CO2 and effective desorption yields were measured at 300, 77, and 6.3 K using single shot and continuous ion bombardment techniques. We find that the heavy-ion-induced desorption yield is temperature dependent and investigate the influence of CO gas cryosorbed at 6.3 K. The gain in desorption yield reduction at cryogenic temperature vanishes after several monolayers of CO are cryosorbed on both targets. In this paper we describe the new cryogenic target assembly, the temperature-dependent pressure rise, desorption yield, and gas adsorption measurements.

  1. Comparison of biomolecule desorption yields for low and high energy primary ions

    International Nuclear Information System (INIS)

    Kamensky, I.; Hakansson, P.; Sundqvist, B.; McNeal, C.J.; MacFarlane, R.

    1982-01-01

    Ion induced desorption yields of molecular ions from samples of cesium iodide, glycylglycine, ergosterol, bleomycin and a trinucleoside diphosphate have been studied using primary beams of 54 MeV 63 Cu 9+ and 3 keV 133 Cs + . Mass analysis was performed with a time-of-flight technique. Each sample was studied with the same spectrometer for both low and high energy primary ions and without opening of the vacuum chamber in between the measurements. The results show that fast heavy ions give larger yields for all samples studied and that the yield ratios for high to low energy desorption increase with the mass of the sample molecule. (orig.)

  2. Energy dependence of ion-induced sputtering yields from monoatomic solids at normal incidence

    International Nuclear Information System (INIS)

    Yamamura, Yasunori; Tawara, Hiro.

    1995-03-01

    The yields of the ion-induced sputtering from monoatomic solids at normal incidence for various ion-target combinations are presented graphically as a function of the incident ion energy. In order to fill the lack of the experimental data, the sputtering yields are also calculated by the Monte Carlo simulation code ACAT for some ion-target combinations. Each graph shows available experimental data points and the ACAT data, together with the sputtering yields calculated by the present empirical formula, whose parameters are determined by the best-fit to available data. (author)

  3. Genotypic Variation in Yield, Yield Components, Root Morphology and Architecture, in Soybean in Relation to Water and Phosphorus Supply

    Science.gov (United States)

    He, Jin; Jin, Yi; Du, Yan-Lei; Wang, Tao; Turner, Neil C.; Yang, Ru-Ping; Siddique, Kadambot H. M.; Li, Feng-Min

    2017-01-01

    Water shortage and low phosphorus (P) availability limit yields in soybean. Roots play important roles in water-limited and P-deficient environment, but the underlying mechanisms are largely unknown. In this study we determined the responses of four soybean [Glycine max (L.) Merr.] genotypes [Huandsedadou (HD), Bailudou (BLD), Jindou 21 (J21), and Zhonghuang 30 (ZH)] to three P levels [applied 0 (P0), 60 (P60), and 120 (P120) mg P kg-1 dry soil to the upper 0.4 m of the soil profile] and two water treatment [well-watered (WW) and water-stressed (WS)] with special reference to root morphology and architecture, we compared yield and its components, root morphology and root architecture to find out which variety and/or what kind of root architecture had high grain yield under P and drought stress. The results showed that water stress and low P, respectively, significantly reduced grain yield by 60 and 40%, daily water use by 66 and 31%, P accumulation by 40 and 80%, and N accumulation by 39 and 65%. The cultivar ZH with the lowest daily water use had the highest grain yield at P60 and P120 under drought. Increased root length was positively associated with N and P accumulation in both the WW and WS treatments, but not with grain yield under water and P deficits. However, in the WS treatment, high adventitious and lateral root densities were associated with high N and P uptake per unit root length which in turn was significantly and positively associated with grain yield. Our results suggest that (1) genetic variation of grain yield, daily water use, P and N accumulation, and root morphology and architecture were observed among the soybean cultivars and ZH had the best yield performance under P and water limited conditions; (2) water has a major influence on nutrient uptake and grain yield, while additional P supply can modestly increase yields under drought in some soybean genotypes; (3) while conserved water use plays an important role in grain yield under drought

  4. Satellite-based studies of maize yield spatial variations and their causes in China

    Science.gov (United States)

    Zhao, Y.

    2013-12-01

    Maize production in China has been expanding significantly in the past two decades, but yield has become relatively stagnant in the past few years, and needs to be improved to meet increasing demand. Multiple studies found that the gap between potential and actual yield of maize is as large as 40% to 60% of yield potential. Although a few major causes of yield gap have been qualitatively identified with surveys, there has not been spatial analysis aimed at quantifying relative importance of specific biophysical and socio-economic causes, information which would be useful for targeting interventions. This study analyzes the causes of yield variation at field and village level in Quzhou county of North China Plain (NCP). We combine remote sensing and crop modeling to estimate yields in 2009-2012, and identify fields that are consistently high or low yielding. To establish the relationship between yield and potential factors, we gather data on those factors through a household survey. We select targeted survey fields such that not only both extremes of yield distribution but also all soil texture categories in the county is covered. Our survey assesses management and biophysical factors as well as social factors such as farmers' access to agronomic knowledge, which is approximated by distance to the closest demonstration plot or 'Science and technology backyard'. Our survey covers 10 townships, 53 villages and 180 fields. Three to ten farmers are surveyed depending on the amount of variation present among sub pixels of each field. According to survey results, we extract the amount of variation within as well as between villages and or soil type. The higher within village or within field variation, the higher importance of management factors. Factors such as soil type and access to knowledge are more represented by between village variation. Through regression and analysis of variance, we gain more quantitative and thorough understanding of causes to yield variation at

  5. High yield antibiotic producing mutants of Streptomyces erythreus induced by low energy ion implantation

    Science.gov (United States)

    Yu, Chen; Zhixin, Lin; Zuyao, Zou; Feng, Zhang; Duo, Liu; Xianghuai, Liu; Jianzhong, Tang; Weimin, Zhu; Bo, Huang

    1998-05-01

    Conidia of Streptomyces erythreus, an industrial microbe, were implanted by nitrogen ions with energy of 40-60 keV and fluence from 1 × 10 11 to 5 × 10 14 ions/cm 2. The logarithm value of survival fraction had good linear relationship with the logarithm value of fluence. Some mutants with a high yield of erythromycin were induced by ion implantation. The yield increment was correlated with the implantation fluence. Compared with the mutation results induced by ultraviolet rays, mutation effects of ion implantation were obvious having higher increasing erythromycin potency and wider mutation spectrum. The spores of Bacillus subtilis were implanted by arsenic ions with energy of 100 keV. The distribution of implanted ions was measured by Rutherford Backscattering Spectrometry (RBS) and calculated in theory. The mechanism of mutation induced by ion implantation was discussed.

  6. A Model for Quantifying Sources of Variation in Test-day Milk Yield ...

    African Journals Online (AJOL)

    A cow's test-day milk yield is influenced by several systematic environmental effects, which have to be removed when estimating the genetic potential of an animal. The present study quantified the variation due to test date and month of test in test-day lactation yield records using full and reduced models. The data consisted ...

  7. Determination of low-energy ion-induced electron yields from thin carbon foils

    International Nuclear Information System (INIS)

    Allegrini, Frederic; Wimmer-Schweingruber, Robert F.; Wurz, Peter; Bochsler, Peter

    2003-01-01

    Ion beams crossing thin carbon foils can cause electron emission from the entrance and exit surface. Thin carbon foils are used in various types of time-of-flight (TOF) mass spectrometers to produce start pulses for TOF measurements. The yield of emitted electrons depends, among other parameters, on the energy of the incoming ion and its mass, and it has been experimentally determined for a few projectile elements. The electron emission yield is of great importance for deriving abundance ratios of elements and isotopes in space plasmas using TOF mass spectrometers. We have developed a detector for measuring ion-induced electron yields, and we have extended the electron yield measurements for oxygen to energies relevant for solar wind research. We also present first measurements of the carbon foil electron emission yield for argon and iron in the solar wind energy range

  8. Dependence of energy per molecule on sputtering yields with reactive gas cluster ions

    International Nuclear Information System (INIS)

    Toyoda, Noriaki; Yamada, Isao

    2010-01-01

    Gas cluster ions show dense energy deposition on a target surface, which result in the enhancement of chemical reactions. In reactive sputtering with gas cluster ions, the energy per atom or molecule plays an important role. In this study, the average cluster size (N, the number of atoms or molecules in a cluster ion) was controlled; thereby the dependences of the energy per molecule on the sputtering yields of carbon by CO 2 cluster ions and that of Si by SF 6 /Ar mixed gas cluster ions were investigated. Large CO 2 cluster ions with energy per molecule of 1 eV showed high reactive sputtering yield of an amorphous carbon film. However, these ions did not cause the formation of large craters on a graphite surface. It is possible to achieve very low damage etching by controlling the energy per molecule of reactive cluster ions. Further, in the case of SF 6 /Ar mixed cluster ions, it was found that reactive sputtering was enhanced when a small amount of SF 6 gas (∼10%) was mixed with Ar. The reactive sputtering yield of Si by one SF 6 molecule linearly increased with the energy per molecule.

  9. Fusion yield rate recovery by escaping hot-spot fast ions in the neighboring fuel layer

    Science.gov (United States)

    Tang, Xian-Zhu; McDevitt, C. J.; Guo, Zehua; Berk, H. L.

    2014-02-01

    Free-streaming loss by fast ions can deplete the tail population in the hot spot of an inertial confinement fusion (ICF) target. Escaping fast ions in the neighboring fuel layer of a cryogenic target can produce a surplus of fast ions locally. In contrast to the Knudsen layer effect that reduces hot-spot fusion reactivity due to tail ion depletion, the inverse Knudsen layer effect increases fusion reactivity in the neighboring fuel layer. In the case of a burning ICF target in the presence of significant hydrodynamic mix which aggravates the Knudsen layer effect, the yield recovery largely compensates for the yield reduction. For mix-dominated sub-ignition targets, the yield reduction is the dominant process.

  10. Study on the desorption yield for natural botanic sample induced by energetic heavy ions

    CERN Document Server

    Xue, J M; Du, G H; Yan, S; Zhao, W J

    2002-01-01

    The dependence of desorption yield for the natural botanic sample bombarded with heavy ion on the electronic stopping power (S sub e) and dose has been measured by weighing sample mass before and after irradiation. Primary ions including 50 keV N sup + , 1.5 MeV F sup + , 3.0 MeV F sup 2 sup + , 4.0 MeV F sup 2 sup + and 3.0 MeV Si sup 2 sup + were used in the experiment. Three megaelectron volts of F sup 2 sup + with doses ranging from 4x10 sup 1 sup 5 to 4x10 sup 1 sup 6 ions/cm sup 2 were used in order to investigate the influence of ion dose. A mass spectrum from the sample bombarded with 3 MeV Si sup 2 sup + was also taken for a better understanding of the desorption process. Results show that the natural botanic sample is very easily to be desorpted. The yield of MeV heavy ions can be as high as thousands CH sub 2 O/ion, and significantly depends on both the S sub e and dose. The measured yields increase quickly with S sub e , but drop down with increasing ion dose. These results fit roughly with the pr...

  11. Study on the desorption yield for natural botanic sample induced by energetic heavy ions

    International Nuclear Information System (INIS)

    Xue, J.M.; Wang, Y.G.; Du, G.H.; Yan, S.; Zhao, W.J.

    2002-01-01

    The dependence of desorption yield for the natural botanic sample bombarded with heavy ion on the electronic stopping power (S e ) and dose has been measured by weighing sample mass before and after irradiation. Primary ions including 50 keV N + , 1.5 MeV F + , 3.0 MeV F 2+ , 4.0 MeV F 2+ and 3.0 MeV Si 2+ were used in the experiment. Three megaelectron volts of F 2+ with doses ranging from 4x10 15 to 4x10 16 ions/cm 2 were used in order to investigate the influence of ion dose. A mass spectrum from the sample bombarded with 3 MeV Si 2+ was also taken for a better understanding of the desorption process. Results show that the natural botanic sample is very easily to be desorpted. The yield of MeV heavy ions can be as high as thousands CH 2 O/ion, and significantly depends on both the S e and dose. The measured yields increase quickly with S e , but drop down with increasing ion dose. These results fit roughly with the prediction of the pressure pulse model

  12. Variations in the milk yield and milk composition of dairy cows during lactation.

    Science.gov (United States)

    Bedö, S; Nikodémusz, E; Percsich, K; Bárdos, L

    1995-01-01

    Variations in the milk yield and milk composition of a dairy cow colony (n = 23) were analyzed during 11 months of lactation. Milk yield followed a characteristic decreasing pattern in negative correlations with solid components (milk protein, lactose, total solids, milk fat). Titrable acidity (degree SH) was significantly (p < 0.1) higher in the milk of fresh-milking cows and it correlated negatively with lactose and positively with milk protein, milk fat and total solids. The concentrations of Zn, Fe and Cu tended to decrease, while Mn showed insignificant variation during lactation. Milk vitamin A showed a significant positive whilst milk vitamin E had a negative correlation with milk fat.

  13. [Accepted Manuscript] Annual Crop Yield Variation, Child Survival and Nutrition among Subsistence Farmers in Burkina Faso.

    OpenAIRE

    Belesova, K.; Gasparrini, A.; Sié, A.; Sauerborn, R.; Wilkinson, P.

    2017-01-01

    Whether year to year variation in crop yields affects the nutrition, health, and survival of subsistence farming populations is relevant to the understanding of the potential impacts of climate change. However, the empirical evidence is limited. We examined the association of child survival with inter-annual variation in food crop yield and middle-upper arm circumference (MUAC) in a subsistence farming population of rural Burkina Faso. The study was of 44,616 children < 5 years of age incl...

  14. [Spatial-temporal variations of spring maize potential yields in a changing climate in Northeast China.

    Science.gov (United States)

    Liu, Zhi Juan; Yang, Xiao Guang; Lyu, Shuo; Wang, Jing; Lin, Xiao Mao

    2018-01-01

    Based on meteorological data, agro-meteorological observations, and agricultural statistical data in Northeast China (NEC), by using the validated Agricultural Production System sIMulator (APSIM-maize), the potential, attainable, potential farmers' and actual farmers' yields of spring maize during the period 1961 to 2015 were analyzed, and the effects of climate variation on maize potential yield in NEC were quantified. Results indicated that the potential yield of spring maize was 12.2 t·hm -2 during the period 1961 to 2015, with those in northeast being lower than southwest within the study region. The attainable yield of spring maize was 11.3 t·hm -2 , and showed a similar spatial distribution with potential yield. Under the current farmers' management practices, mean simulated potential and actual farmers' yields were 6.5 and 4.5 t·hm -2 , respectively. Assuming there were no changes in cultivars and management practices in NEC, the mean potential, attainable, and potential farmers' yields of spring maize would decrease by 0.34, 0.25 and 0.10 t·hm -2 per decade in NEC. However, the actual farmers' yields increased with the value of 1.27 t·hm -2 per decade averaged over NEC. Due to climate variation, year-to-year variations of spring maize potential, attainable, and potential farmers' yields were significant, ranging from 10.0 to 14.4, 9.8 to 13.3, 4.4 to 8.5 t·hm -2 , respectively.

  15. Variation of inulin content, inulin yield and water use efficiency for inulin yield in Jerusalem artichoke genotypes under different water regimes

    Science.gov (United States)

    The information on genotypic variation for inulin content, inulin yield and water use efficiency of inulin yield (WUEi) in response to drought is limited. This study was to investigate the genetic variability in inulin content, inulin yield and WUEi of Jerusalem artichoke (Helianthus tuberosus L.) ...

  16. Estimates of Sputter Yields of Solar-Wind Heavy Ions of Lunar Regolith Materials

    Science.gov (United States)

    Barghouty, Abdulmasser F.; Adams, James H., Jr.

    2008-01-01

    At energies of approximately 1 keV/amu, solar-wind protons and heavy ions interact with the lunar surface materials via a number of microscopic interactions that include sputtering. Solar-wind induced sputtering is a main mechanism by which the composition of the topmost layers of the lunar surface can change, dynamically and preferentially. This work concentrates on sputtering induced by solar-wind heavy ions. Sputtering associated with slow (speeds the electrons speed in its first Bohr orbit) and highly charged ions are known to include both kinetic and potential sputtering. Potential sputtering enjoys some unique characteristics that makes it of special interest to lunar science and exploration. Unlike the yield from kinetic sputtering where simulation and approximation schemes exist, the yield from potential sputtering is not as easy to estimate. This work will present a preliminary numerical scheme designed to estimate potential sputtering yields from reactions relevant to this aspect of solar-wind lunar-surface coupling.

  17. Variation of Potential Yield of Hybrid Population of Robusta coffee (Coffea canepor

    Directory of Open Access Journals (Sweden)

    Novie Pranata Erdiansyah

    2014-08-01

    Full Text Available The low yield of Robusta coffee in Indonesia may be due to the use of planting materials derived from seeds. The research objective was to determine the variation of Robusta coffee yield wich local propagated by using seeds. The study was conducted in Kaliwining experimental Station of ICCRI (Indonesian Coffee andCocoa Research Institute. There were two populations observed. Number of progeny used in this study were 186 genotypes consisting of two groups from crossesBP 409 x Q 121 with 89 progenies and BP 961 x BP 409 with 81 progenies. The results showed that planting materials from seeds exhibit properties mixed results.Progeny that have the best results (yield more than 2 ton/ha not more than 5% of the total population. In both populations there is a big difference between the progenythat has high and low yield. Highest yield B population could reach 2,500 kg/ha and the C population reached 2,200 kg/ha. The lowest yield can only produce coffee270 kg/ha in populations B and 120 kg/ha in population C.Key words: Coffea canephora, hybrid, variation, yield

  18. Isobaric yield ratios and the symmetry energy in heavy-ion reactions near the Fermi energy

    International Nuclear Information System (INIS)

    Huang, M.; Chen, Z.; Kowalski, S.; Ma, Y. G.; Wada, R.; Hagel, K.; Barbui, M.; Bottosso, C.; Materna, T.; Natowitz, J. B.; Qin, L.; Rodrigues, M. R. D.; Sahu, P. K.; Keutgen, T.; Bonasera, A.; Wang, J.

    2010-01-01

    The relative isobaric yields of fragments produced in a series of heavy-ion-induced multifragmentation reactions have been analyzed in the framework of a modified Fisher model, primarily to determine the ratio of the symmetry energy coefficient to the temperature, a sym /T, as a function of fragment mass A. The extracted values increase from 5 to ∼16 as A increases from 9 to 37. These values have been compared to the results of calculations using the antisymmetrized molecular dynamics (AMD) model together with the statistical decay code gemini. The calculated ratios are in good agreement with those extracted from the experiment. In contrast, the values extracted from the ratios of the primary isobars from the AMD model calculation are ∼4 to 5 and show little variation with A. This observation indicates that the value of the symmetry energy coefficient derived from final fragment observables may be significantly different than the actual value at the time of fragment formation. The experimentally observed pairing effect is also studied within the same simulations. The Coulomb coefficient is also discussed.

  19. Paradoxes of photoconductive target and optical control of secondary ion yield

    International Nuclear Information System (INIS)

    Rokakh, A. G.; Matasov, M. D.

    2010-01-01

    This study of the photoconductivity of semiconductors, in particular, cadmium chalcogenides as materials for targets of vacuum image converters followed the path of overcoming paradoxes. The concepts developed by the classics of photoelectricity also help to understand the paradoxes of the new secondary-ion photoelectric effect, especially, its spectral characteristic. The optical channel of secondary ion yield control via a photoconductive target opens the way to a new branch of nanotechnology, i.e., optoionics.

  20. Dependence of simulated positron emitter yields in ion beam cancer therapy on modeling nuclear fragmentation

    DEFF Research Database (Denmark)

    Lühr, Armin; Priegnitz, Marlen; Fiedler, Fine

    2014-01-01

    In ion beam cancer therapy, range verification in patients using positron emission tomography (PET) requires the comparison of measured with simulated positron emitter yields. We found that (1) changes in modeling nuclear interactions strongly affected the positron emitter yields and that (2) Monte...... Carlo simulations with SHIELD-HIT10A reasonably matched the most abundant PET isotopes 11C and 15O. We observed an ion-energy (i.e., depth) dependence of the agreement between SHIELD-HIT10A and measurement. Improved modeling requires more accurate measurements of cross-section values....

  1. Screening on the high yield validamycin producing strain by implantation with N+ and Ti+ ion source

    International Nuclear Information System (INIS)

    Yu Long; An Xiao

    2007-01-01

    In order to compared the mutagenic effects of the validamycin producing the strain (Streptomyces hygroscopicus var. Jingganggensis Yen.) was implanted with two kinds of ion sources. The results showed that when two kinds of ion sources implanted into the strain by turns, more positive mutants and higher yield would be acquired. Using this method, a high-yielding strain B1-3 was obtained, which produce the titer of validamycin A of 21514, and was 54.4% higher than that of the original strain. (authors)

  2. Variation and Inter-relationship ,Between Yield aJld,SQQl

    African Journals Online (AJOL)

    Variation and Inter-relationship ,Between Yield aJld,SQQl~ ",,,',, ... Analysis of variance revealed sigiiificaiit'differences, among the-teSted. • .:' '. J ~ I .... Successful use of. muta~ "number of panicles,~r~~ metre,', 100Q,grain ... ponents and to assess genetic x ,environment inter- , individual traits, estimates of error phenotYpic,.

  3. Responses of Winter Wheat Yields to Warming-Mediated Vernalization Variations Across Temperate Europe

    Directory of Open Access Journals (Sweden)

    Xiuchen Wu

    2017-10-01

    Full Text Available Rapid climate warming, with much higher warming rates in winter and spring, could affect the vernalization fulfillment, a critical process for induction of crop reproductive growth and consequent grain filling in temperate winter crops. However, regional observational evidence of the effects of historical warming-mediated vernalization variations on temperate winter crop yields is lacking. Here, we statistically quantified the interannual sensitivity of winter wheat yields to vernalization degree days (VDD during 1975–2009 and its spatial relationship with multi-year mean VDD over temperate Europe (TE, using EUROSTAT crop yield statistics, observed and simulated crop phenology data and gridded daily climate data. Our results revealed a pervasively positive interannual sensitivity of winter wheat yields to variations in VDD (γVDD over TE, with a mean γVDD of 2.8 ± 1.5 kg ha−1 VDD−1. We revealed a significant (p < 0.05 negative exponential relationship between γVDD and multi-year mean VDD for winter wheat across TE, with higher γVDD in winter wheat planting areas with lower multi-year mean VDD. Our findings shed light on potential vulnerability of winter wheat yields to warming-mediated vernalization variations over TE, particularly considering a likely future warmer climate.

  4. Annual variations in seed yield and implications for multiple use of crabwood

    Directory of Open Access Journals (Sweden)

    Helio Tonini

    2017-12-01

    Full Text Available The objective of this study was to evaluate the annual variation in seed yield of crabwood, and discuss implications for multiple use management of the species. Data were collected in a forest area in the southern of Roraima State in a permanent plot of 9 ha (300 m x 300 m with a natural population of crabwood. Seed production was monitored of 115 trees during four years. Seed yield varied among years. May to July was the period of bigger yield. Few trees (22.6% concentrated the bigger part of seeds yield (80.7% and the most productive trees had diameter at 1.30 m above ground level between 40 cm - 70 cm. Therefore we recommend 70 cm as minimum cutting diameter for wood exploitation. For sustainable crabwood seed management we recommend to restrict seed collection from the most productive trees and only during the period of maximum seed dispersal.

  5. Analytical evaluation for the sputtering yield of monoatomic solids at normal ion incidence

    International Nuclear Information System (INIS)

    Shao Qiyun; Pan Zhengying

    1994-01-01

    A universal formula of sputtering yield for normal incidence of mono-energetic ions on single element targets is presented. The results based on this method are compared with the Monte Carlo simulation and the experimental data. By means of Wilcoxon two-sample paired signed rank test, the statistically significant difference of the above results is discussed

  6. Excessive Yield of Second Charged ions of Heavy Elements in Laser Plasma Expansion Process

    International Nuclear Information System (INIS)

    Kouznetsov, G.B.; Sysoev, A.A.

    2002-01-01

    LAMAS-IOM TOF-MS that was recently designed for inorganic quantitative analysis is also well suitable for investigation of laser irradiation interaction with solids. This feature allows one to analyze plasma on early stage and gives an excellent possibility to complete existent physical model. This work is dedicated to investigation of yield doubly charged ions for different elements

  7. uv laser induced molecular multiphoton ionization and fragmentation. [Intensity dependence, ion properties and yield

    Energy Technology Data Exchange (ETDEWEB)

    Rockwood, S; Reilly, J P; Hohla, K; Kompa, K L

    1979-02-01

    It has been demonstrated that the output from a discharge pumped KrF laser (249 nm) is capable of ionizing a variety of molecules. The nature and yield of ions generated in this process, which were identified by time-of-flight mass spectrometry, exhibit a striking intensity dependence. 12 references, 3 figures.

  8. Relative ion yields in mammalian cell components using C60 SIMS

    Science.gov (United States)

    Keskin, Selda; Piwowar, Alan; Hue, Jonathan; Shen, Kan; Winograd, Nicholas

    2013-01-01

    Time of flight secondary ion mass spectrometry has been used to better understand the influence of molecular environment on the relative ion yields of membrane lipid molecules found in high abundance in a model mammalian cell line, RAW264.7. Control lipid mixtures were prepared to simulate lipid–lipid interactions in the inner and outer leaflet of cell membranes. Compared with its pure film, the molecular ion yields of 1,2-dioleoyl-sn-glycero-3-phosphocholine and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine are suppressed when mixed with 2-dipalmitoyl-sn-glycero-3-phosphocholine. In the mixture, proton competition between 1,2-dioleoyl-sn-glycero-3-phosphocholine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, and 2-dipalmitoyl-sn-glycero-3-phosphocholine led to lower ionization efficiency. The possible mechanism for ion suppression was also investigated with 1H and 13C nuclear magnetic resonance spectroscopy. The formation of a hydroxyl bond in lipid mixtures confirms the mechanism involving proton exchange with the surrounding environment. Similar effects were observed for lipid mixtures mimicking the composition of the inner leaflet of cell membranes. The secondary molecular ion yield of 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-L-serine was observed to be enhanced in the presence of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine. PMID:25140069

  9. Annual Crop-Yield Variation, Child Survival, and Nutrition Among Subsistence Farmers in Burkina Faso.

    Science.gov (United States)

    Belesova, Kristine; Gasparrini, Antonio; Sié, Ali; Sauerborn, Rainer; Wilkinson, Paul

    2018-02-01

    Whether year-to-year variation in crop yields affects the nutrition, health, and survival of subsistence-farming populations is relevant to the understanding of the potential impacts of climate change. However, the empirical evidence is limited. We examined the associations of child survival with interannual variation in food crop yield and middle-upper arm circumference (MUAC) in a subsistence-farming population of rural Burkina Faso. The study was of 44,616 children aged Demographic Surveillance System, 1992-2012, whose survival was analyzed in relation to the food crop yield in the year of birth (which ranged from 65% to 120% of the period average) and, for a subset of 16,698 children, to MUAC, using shared-frailty Cox proportional hazards models. Survival was appreciably worse in children born in years with low yield (full-adjustment hazard ratio = 1.11 (95% confidence interval: 1.02, 1.20) for a 90th- to 10th-centile decrease in annual crop yield) and in children with small MUAC (hazard ratio = 2.72 (95% confidence interval: 2.15, 3.44) for a 90th- to 10th-centile decrease in MUAC). These results suggest an adverse impact of variations in crop yields, which could increase under climate change. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Selected Constituent Yield Variation in the Smoke of Commercial Cigarette Brands on the Japanese Market

    Directory of Open Access Journals (Sweden)

    Hyodo Takatsugu

    2017-12-01

    Full Text Available This study focused on the variation in the yields of constituents in smoke from commercial cigarette brands available on the Japanese market. Nineteen commercial cigarette brands were sampled five times every two months from 2009 to 2010. The target constituents were benzo[a]-pyrene, 1,3-butadiene, benzene, formaldehyde, acetaldehyde, acrolein, N-nitrosonornicotine (NNN, 4-(methylnitrosamino-1-(3-pyridyl-1-butanone (NNK, carbon monoxide, “tar”, and nicotine. The results of this study showed that the coefficient of variation (CV values varied greatly by brands, constituents, and smoking regimes. The yields of NNN and NNK in the smoke were strongly correlated to their yields in the tobacco filler blend for most brands. The yields of benzo[a]pyrene under the International Organization for Standardization (ISO and the Health Canada Intense (HCI smoking regimes and 1,3-butadiene under the HCI smoking regime were found to be influenced by the measurement. It was shown that factors for variation were highly varied among constituents. The grand mean of CV values for NNN and formaldehyde associated with cigarette manufacturing over ten months and measurement at the JT laboratory under the HCI smoking regimes were 17.1% and 6.6% respectively. The grand mean of CV values for NNN and formaldehyde associated with both cigarette manufacturing over ten months and measurement at different laboratories under the HCI smoking regimes were 23.7% and 22.9% respectively. This is due to the fact that formaldehyde showed the highest CV values for reproducibility among the constituents. Thus, in order to set realistic and robust confidence intervals, it is very important to take into account the variations associated with cigarette manufacturing and measurement within and between laboratories.

  11. A Permanent-Magnet Microwave Ion Source for a Compact High-Yield Neutron Generator

    International Nuclear Information System (INIS)

    Waldmann, Ole; Ludewigt, Bernhard

    2010-01-01

    We present recent work on the development of a microwave ion source that will be used in a high-yield compact neutron generator for active interrogation applications. The sealed tube generator will be capable of producing high neutron yields, 5 · 10 11 n/s for D-T and ∼ 1 · 10 10 n/s for D-D reactions, while remaining transportable. We constructed a microwave ion source (2.45 GHz) with permanent magnets to provide the magnetic field strength of 87.5 mT necessary for satisfying the electron cyclotron resonance (ECR) condition. Microwave ion sources can produce high extracted beam currents at the low gas pressures required for sealed tube operation and at lower power levels than previously used RF-driven ion sources. A 100 mA deuterium/tritium beam will be extracted through a large slit (60 · 6 mm 2 ) to spread the beam power over a larger target area. This paper describes the design of the permanent-magnet microwave ion source and discusses the impact of the magnetic field design on the source performance. The required equivalent proton beam current density of 40 mA/cm 2 was extracted at a moderate microwave power of 400 W with an optimized magnetic field.

  12. Free ion yield observed in liquid isooctane irradiated by γ rays. Comparison with the Onsager theory

    International Nuclear Information System (INIS)

    Pardo, J; Franco, L; Gomez, F; Iglesias, A; Lobato, R; Mosquera, J; Pazos, A; Pena, J; Pombar, M; RodrIguez, A; Sendon, J

    2004-01-01

    We have analysed data on the free ion yield observed in liquid isooctane irradiated by 60 Co γ rays within the framework of the Onsager theory about initial recombination. Several distribution functions describing the electron thermalization distance have been used and compared with the experimental results: a delta function, a Gaussian-type function and an exponential function. A linear dependence between the free ion yield and the external electric field has been found at low-electric-field values (E ≤ 1.2 x 10 3 V mm -1 ) in excellent agreement with the Onsager theory. At higher electric field values, we obtain a solution in power series of the external field using the Onsager theory

  13. Free ion yield observed in liquid isooctane irradiated by {gamma} rays. Comparison with the Onsager theory

    Energy Technology Data Exchange (ETDEWEB)

    Pardo, J [Departamento de FIsica de PartIculas, Facultade de FIsica, 15782 Santiago de Compostela (Spain); Franco, L [Departamento de FIsica de PartIculas, Facultade de FIsica, 15782 Santiago de Compostela (Spain); Gomez, F [Departamento de FIsica de PartIculas, Facultade de FIsica, 15782 Santiago de Compostela (Spain); Iglesias, A [Departamento de FIsica de PartIculas, Facultade de FIsica, 15782 Santiago de Compostela (Spain); Lobato, R [Hospital ClInico Universitario de Santiago, Santiago de Compostela (Spain); Mosquera, J [Hospital ClInico Universitario de Santiago, Santiago de Compostela (Spain); Pazos, A [Departamento de FIsica de PartIculas, Facultade de FIsica, 15782 Santiago de Compostela (Spain); Pena, J [Departamento de FIsica de PartIculas, Facultade de FIsica, 15782 Santiago de Compostela (Spain); Pombar, M [Hospital ClInico Universitario de Santiago, Santiago de Compostela (Spain); RodrIguez, A [Departamento de FIsica de PartIculas, Facultade de FIsica, 15782 Santiago de Compostela (Spain); Sendon, J [Hospital ClInico Universitario de Santiago, Santiago de Compostela (Spain)

    2004-05-21

    We have analysed data on the free ion yield observed in liquid isooctane irradiated by {sup 60}Co {gamma} rays within the framework of the Onsager theory about initial recombination. Several distribution functions describing the electron thermalization distance have been used and compared with the experimental results: a delta function, a Gaussian-type function and an exponential function. A linear dependence between the free ion yield and the external electric field has been found at low-electric-field values (E {<=} 1.2 x 10{sup 3} V mm{sup -1}) in excellent agreement with the Onsager theory. At higher electric field values, we obtain a solution in power series of the external field using the Onsager theory.

  14. Dwell time dependent morphological transition and sputtering yield of ion sputtered Sn

    International Nuclear Information System (INIS)

    Qian, H X; Zeng, X R; Zhou, W

    2010-01-01

    Self-organized nano-scale patterns may appear on a wide variety of materials irradiated with an ion beam. Good manipulation of these structures is important for application in nanostructure fabrication. In this paper, dwell time has been demonstrated to be able to control the ripple formation and sputtering yield on Sn surface. Ripples with a wavelength of 1.7 μm were observed for a dwell time in the range 3-20 μs, whereas much finer ripples with a wavelength of 540 nm and a different orientation were observed for a shorter dwell time in the range 0.1-2 μs. The sputtering yield increases with dwell time significantly. The results provide a new basis for further steps in the theoretical description of morphology evolution during ion beam sputtering.

  15. Electron mobility and saturation of ion yield in 2,2,4,4-tetramethylpentane

    International Nuclear Information System (INIS)

    Poffenberger, P.R.; Astbury, A.; Fincke-Keeler, M.; Keeler, R.K.; Li, Y.; Robertson, L.P.; Rosvick, M.; Schenk, P.; Oram, C.; Sobie, R.

    1993-01-01

    The electron drift mobility μ and zero field free ion yield G fi 0 have been measured for liquid 2,2,4,4-tetramethylpentane using a waveform analysis. The saturation of the ion yield for highly ionizing radiation has also been investigated and parameterized using the Birks' equation. The results obtained are μ=26.3±0.8 cm 2 /V s, G fi 0 =0.743±0.029 electrons/100 eV, and a Birks' factor ranging from kB=0.222±0.014 cm/MeV at 604 V/cm to kB=0.141±0.021 cm/MeV at 3625 V/cm. (orig.)

  16. Ion yields of laser aligned CH3I and CH3Br from multiple orbitals

    NARCIS (Netherlands)

    He, Lanhai; Pan, Yun; Yang, Yujun; Luo, Sizuo; Lu, Chunjing; Zhao, Huifang; Li, Dongxu; Song, Lele; Stolte, Steven; Ding, Dajun; Roeterdink, Wim G.

    2016-01-01

    We have measured the alignment influence on ion yields of CH3I and CH3Br molecules in the laser intensity regime from 1013 W/cm2 to 1015 W/cm2. The hexapole state-selection technique combined with laser induced alignment has been employed to obtain aligned (〈P2(cosθ)〉=0.7) and anti-aligned

  17. Monte Carlo simulation for neutron yield produced by bombarding thick targets with high energy heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Oranj, Leila Mokhtari; Oh, Joo Hee; Yoon, Moo Hyun; Lee, Hee Seock [POSTECH, Pohang (Korea, Republic of)

    2013-04-15

    One of radiation shielding issues at heavy-ion accelerator facilities is to estimate neutron production by primary heavy ions. A few Monte Carlo transport codes such as FLUKA and PHITS can work with primary heavy ions. Recently IBS/RISP((Rare Isotope Science Project) started to design a high-energy, high-power rare isotope accelerator complex for nuclear physics, medical and material science and applications. There is a lack of experimental and simulated data about the interaction of major beam, {sup 238}U with materials. For the shielding design of the end of first accelerating section section, we calculate a differential neutron yield using the FLUKA code for the interaction of 18.5 MeV/u uranium ion beam with thin carbon stripper of 1.3 μm). The benchmarking studies were also done to prove the yield calculation for 400 MeV/n {sup 131}Xe and other heavy ions. In this study, the benchmarking for Xe-C, Xe-Cu, Xe-Al, Xe-Pb and U-C, other interactions were performed using the FLUKA code. All of results show that the FLUKA can evaluate the heavy ion induced reaction with good uncertainty. For the evaluation of neutron source term, the calculated neutron yields are shown in Fig. 2. The energy of Uranium ion beam is only 18.5 MeV/u, but the energy of produced secondary neutrons was extended over 100 MeV. So the neutron shielding and the damage by those neutrons is expected to be serious. Because of thin stripper, the neutron intensity at forward direction was high. But the the intensity of produced secondary photons was relatively low and mostly the angular property was isotropic. For the detail shielding design of stripper section of RISP rare istope accelerator, the benchmarking study and preliminary evaluation of neutron source term from uranium beam have been carried out using the FLUKA code. This study is also compared with the evaluation results using the PHITS code performed coincidently. Both studies shows that two monte carlo codes can give a good results for

  18. Simulation of the molecular recombination yield for swift H2+ ions through thin carbon foils

    International Nuclear Information System (INIS)

    Garcia-Molina, Rafael; Barriga-Carrasco, Manuel D.

    2003-01-01

    We have calculated the recombination yield for swift H 2 + molecular ions at the exit of thin amorphous carbon foils, as a function of the dwell time and incident energy. Our results are based on a detailed simulation of the motion through the target of the H 2 + molecular ion (before dissociation takes place) and its constituent fragments (after dissociation), including the following effects: Coulomb repulsion, nuclear scattering, electron capture and loss, as well as self-retarding and wake forces, which provide the relative distance and velocity of the dissociated fragments at the foil exit. The recombination of an H 2 + ion at the exit of the foil depends on the interproton separation and internal energy of the dissociated fragments, and on their probability to capture an electron. Comparison of our results with the available experimental data shows a good agreement

  19. X-ray yields by low energy heavy ion excitation in alkali halide solid targets

    International Nuclear Information System (INIS)

    Kurup, M.B.; Prasad, K.G.; Sharma, R.P.

    1981-01-01

    Solid targets of the alkali halides KCl, NaCl and KBr are bombarded with ion beams of 35 Cl + , 40 Ar + and 63 Cu + in the energy range 165 keV to 320 keV. The MO and characteristic K X-ray yields resulting from the ion-atom collision have been systematically studied. Both MO and Cl K X-ray yields are enhanced by factors 3.5 and 2 respectively in KCl targets as compared to that in NaCl when bombarded with either Cl + or Ar + projectiles. An intercomparison of MO and K X-ray yields for a given projectile-target combination has shown that the latter increases ten times faster than the former as the energy of the projectile is increased from 165 to 320 keV indicating a correspondingly stronger velocity dependence of the K X-ray production process. The X-ray yields observed in the symmetric Cl-Cl collision are identical to those observed in the asymmetric Ar-Cl collision for the same projectile velocities in both KCl and NaCl targets. It is inferred that the multiple ionization of the projectile resulting in an increase in the binding energy of its inner shells offsets the expected enhancement in the X-ray yields in a symmetric collision. The same projectiles, Ar or Cl, incident on KBr targets have produced only Br L X-rays. Using substantially heavier projectiles than the target atoms (Na, K and Cl), like 63 Cu + ions, the inner shell excitation by recoiling atoms is shown. (orig.)

  20. Grain size effect on yield strength of titanium alloy implanted with aluminum ions

    Energy Technology Data Exchange (ETDEWEB)

    Popova, Natalya, E-mail: natalya-popova-44@mail.ru [Tomsk State University of Architecture and Building, 2, Solyanaya Sq., 634003, Tomsk (Russian Federation); Institute of Strength Physics and Materials Science, SB RAS, 2/4, Akademicheskii Ave., 634021, Tomsk (Russian Federation); Nikonenko, Elena, E-mail: vilatomsk@mail.ru [Tomsk State University of Architecture and Building, 2, Solyanaya Sq., 634003, Tomsk (Russian Federation); National Research Tomsk Polytechnic University, 30, Lenin Str., 634050, Tomsk (Russian Federation); Yurev, Ivan, E-mail: yiywork@mail.ru [Tomsk State University of Architecture and Building, 2, Solyanaya Sq., 634003, Tomsk (Russian Federation); Kalashnikov, Mark, E-mail: kmp1980@mail.ru [Institute of Strength Physics and Materials Science, SB RAS, 2/4, Akademicheskii Ave., 634021, Tomsk (Russian Federation); Kurzina, Irina, E-mail: kurzina99@mail.ru [National Research Tomsk State University, 36, Lenin Str., 634050, Tomsk (Russian Federation)

    2016-01-15

    The paper presents a transmission electron microscopy (TEM) study of the microstructure and phase state of commercially pure titanium VT1-0 implanted by aluminum ions. This study has been carried out before and after the ion implantation for different grain size, i.e. 0.3 µm (ultra-fine grain condition), 1.5 µm (fine grain condition), and 17 µm (polycrystalline condition). This paper presents details of calculations and analysis of strength components of the yield stress. It is shown that the ion implantation results in a considerable hardening of the entire thickness of the implanted layer in the both grain types. The grain size has, however, a different effect on the yield stress. So, both before and after the ion implantation, the increase of the grain size leads to the decrease of the alloy hardening. Thus, hardening in ultra-fine and fine grain alloys increased by four times, while in polycrystalline alloy it increased by over six times.

  1. Variation in shoot tolerance mechanisms not related to ion toxicity in barley

    KAUST Repository

    Tilbrook, Joanne

    2017-09-27

    Soil salinity can severely reduce crop growth and yield. Many studies have investigated salinity tolerance mechanisms in cereals using phenotypes that are relatively easy to measure. The majority of these studies measured the accumulation of shoot Na+ and the effect this has on plant growth. However, plant growth is reduced immediately after exposure to NaCl before Na+ accumulates to toxic concentrations in the shoot. In this study, nondestructive and destructive measurements are used to evaluate the responses of 24 predominately Australian barley (Hordeum vulgare L.) lines at 0, 150 and 250mMNaCl. Considerable variation for shoot tolerance mechanisms not related to ion toxicity (shoot ion-independent tolerance) was found, withsome lines being able to maintain substantial growth rates under salt stress, whereas others stopped growing. Hordeum vulgare spp. spontaneum accessions and barley landraces predominantly had the best shoot ion independent tolerance, although two commercial cultivars, Fathom and Skiff, also had high tolerance. The tolerance of cv. Fathom may be caused by a recent introgression from H. vulgare L. spp. spontaneum. This study shows that the most salt-tolerant barley lines are those that contain both shoot ion-independent tolerance and the ability to exclude Na+ from the shoot (and thus maintain high K+: Na+ ratios).

  2. Variation in shoot tolerance mechanisms not related to ion toxicity in barley

    KAUST Repository

    Tilbrook, Joanne; Schilling, Rhiannon K.; Berger, Bettina; Garcia, Alexandre F.; Trittermann, Christine; Coventry, Stewart; Rabie, Huwaida; Brien, Chris; Nguyen, Martin; Tester, Mark A.; Roy, Stuart J.

    2017-01-01

    Soil salinity can severely reduce crop growth and yield. Many studies have investigated salinity tolerance mechanisms in cereals using phenotypes that are relatively easy to measure. The majority of these studies measured the accumulation of shoot Na+ and the effect this has on plant growth. However, plant growth is reduced immediately after exposure to NaCl before Na+ accumulates to toxic concentrations in the shoot. In this study, nondestructive and destructive measurements are used to evaluate the responses of 24 predominately Australian barley (Hordeum vulgare L.) lines at 0, 150 and 250mMNaCl. Considerable variation for shoot tolerance mechanisms not related to ion toxicity (shoot ion-independent tolerance) was found, withsome lines being able to maintain substantial growth rates under salt stress, whereas others stopped growing. Hordeum vulgare spp. spontaneum accessions and barley landraces predominantly had the best shoot ion independent tolerance, although two commercial cultivars, Fathom and Skiff, also had high tolerance. The tolerance of cv. Fathom may be caused by a recent introgression from H. vulgare L. spp. spontaneum. This study shows that the most salt-tolerant barley lines are those that contain both shoot ion-independent tolerance and the ability to exclude Na+ from the shoot (and thus maintain high K+: Na+ ratios).

  3. Emittance variations in current-amplifying ion induction linacs

    International Nuclear Information System (INIS)

    Fessenden, T.J.

    1991-01-01

    Since 1985 the Heavy Ion Fusion Accelerator Research program at the Lawrence Berkeley Laboratory has been studying current amplification and emittance variations in MBE-4, a four-cesium-beam induction linac. This experiment models much of the accelerator physics of the electrostatically focused section of a fusion driver. Four space-charge dominated Cs + beams, initially about one meter in length at currents of 5-10 mA, are focused by electrostatic quadrupoles and accelerated in parallel from approximately 200 keV up to one MeV by 24 accelerating gaps. Final currents of 20-40 mA per beam are typical. Recent experiments with extremely low emittance beams (var-epsilon n =0.03 mm-mRad) have investigated variations of transverse and longitudinal normalized emittance for drifting and accelerating beams. These very strongly tune-depressed beams (σ 0 =72 degree, σ∼6 degree) are difficult to match to the accelerator so as to avoid emittance growth during acceleration. During transport strong emittance fluctuations are observed in good qualitative agreement with simulations. Warmer beams with less tune depression exhibit little to no emittance growth, show smaller emittance fluctuations, and are much easier to match. A summary of findings from the MBE-4 studies is presented

  4. Emittance variations in current-amplifying ion induction linacs

    International Nuclear Information System (INIS)

    Fessenden, T.J.

    1991-04-01

    Since 1985 the Heavy Ion Fusion Accelerator Research program at the Lawrence Berkeley Laboratory has been studying current amplification and emittance variations in MBE-4, a four-cesium-beam induction linac. This experiment models much of the accelerator physics of the electrostatically focused section of a fusion driver. Four space-charge dominated Cs + beams, initially about one meter in length at currents of 5--10 mA, are focused by electrostatic quadrupoles and accelerated in parallel from approximately 200 keV up to one MeV by 24 accelerating gaps. Final currents of 20--40 mA per beam are typical. Recent experiments with extremely low emittance beams (ε n = 0.03 mm-mRad) have investigated variations of transverse and longitudinal normalized emittance for drifting and accelerating beams. These very strongly tune-depressed beams (σ o = 72 degrees, σ∼6 degree) are difficult to match the accelerator so as to avoid emittance growth during acceleration. During transport strong emittance fluctuations are observed in good qualitative agreement with simulations. Warmer beams with less tune depression exhibit little to no emittance growth, show smaller emittance fluctuations, and are much easier to match. A summary of findings from the MBE-4 studies is presented. 12 refs., 8 figs

  5. Assessing spatiotemporal variation of drought and its impact on maize yield in Northeast China

    Science.gov (United States)

    Guo, Enliang; Liu, Xingpeng; Zhang, Jiquan; Wang, Yongfang; Wang, Cailin; Wang, Rui; Li, Danjun

    2017-10-01

    In the context of global climate change, drought has become an important factor that affects the maize yield in China. To analyse the impact of drought on maize yield loss in Northeast China in current and future climate scenarios, the Composite Meteorological Drought Index (CI) is introduced to reconstruct the following drought indicators: drought accumulative days (DAD), drought accumulative intensity (DAI), and consecutive drought days (CDD). These three drought indicators are used to describe the three-dimensional characteristics of drought in this study. Sen's slope method and three-dimensional copula functions are adopted to analyse the variety of drought features, and Ensemble Empirical Mode Decomposition (EEMD) is used to analyse the variations in maize yield. A temporal assessment of the standardized yield residuals series (SYRS) of maize from 1961 to 2014 is conducted. A panel regression model is applied to demonstrate the drought impact on maize yield at various growth stages under the RCP4.5 scenario. The results show that the drought risk level for midwest Jilin Province, western Liaoning, and eastern Heilongjiang increase with global warming in the current scenario. The shorter three-dimensional joint return periods, 44-80 yr, were mainly located in western Jilin Province, Liaodong Peninsula, and northwestern Liaoning. Eastern Heilongjiang has a slightly longer joint return period of 80-100 yr. The SYRS shows a strong statistical correlation with drought indicator variations; drought-prone regions exhibit strong positive correlations. In comparison, excess precipitation regions show strong negative correlations with drought indicators in most growth stages. Drought indicators have a relatively strong association with SYRS at the milky-mature maize growth stage, and the occurrence of drought during this period primarily determines the maize yield changes in the future. Maize yield changes are -2.04%, -2.65% and -1.57% for Liaoning, Jilin, and

  6. Heavy ion irradiation of crystalline water ice. Cosmic ray amorphisation cross-section and sputtering yield

    Science.gov (United States)

    Dartois, E.; Augé, B.; Boduch, P.; Brunetto, R.; Chabot, M.; Domaracka, A.; Ding, J. J.; Kamalou, O.; Lv, X. Y.; Rothard, H.; da Silveira, E. F.; Thomas, J. C.

    2015-04-01

    Context. Under cosmic irradiation, the interstellar water ice mantles evolve towards a compact amorphous state. Crystalline ice amorphisation was previously monitored mainly in the keV to hundreds of keV ion energies. Aims: We experimentally investigate heavy ion irradiation amorphisation of crystalline ice, at high energies closer to true cosmic rays, and explore the water-ice sputtering yield. Methods: We irradiated thin crystalline ice films with MeV to GeV swift ion beams, produced at the GANIL accelerator. The ice infrared spectral evolution as a function of fluence is monitored with in-situ infrared spectroscopy (induced amorphisation of the initial crystalline state into a compact amorphous phase). Results: The crystalline ice amorphisation cross-section is measured in the high electronic stopping-power range for different temperatures. At large fluence, the ice sputtering is measured on the infrared spectra, and the fitted sputtering-yield dependence, combined with previous measurements, is quadratic over three decades of electronic stopping power. Conclusions: The final state of cosmic ray irradiation for porous amorphous and crystalline ice, as monitored by infrared spectroscopy, is the same, but with a large difference in cross-section, hence in time scale in an astrophysical context. The cosmic ray water-ice sputtering rates compete with the UV photodesorption yields reported in the literature. The prevalence of direct cosmic ray sputtering over cosmic-ray induced photons photodesorption may be particularly true for ices strongly bonded to the ice mantles surfaces, such as hydrogen-bonded ice structures or more generally the so-called polar ices. Experiments performed at the Grand Accélérateur National d'Ions Lourds (GANIL) Caen, France. Part of this work has been financed by the French INSU-CNRS programme "Physique et Chimie du Milieu Interstellaire" (PCMI) and the ANR IGLIAS.

  7. Modelling spatial and temporal variations of annual suspended sediment yields from small agricultural catchments.

    Science.gov (United States)

    Rymszewicz, A; Bruen, M; O'Sullivan, J J; Turner, J N; Lawler, D M; Harrington, J R; Conroy, E; Kelly-Quinn, M

    2018-04-01

    Estimates of sediment yield are important for ecological and geomorphological assessment of fluvial systems and for assessment of soil erosion within a catchment. Many regulatory frameworks, such as the Convention for the Protection of the Marine Environment of the North-East Atlantic, derived from the Oslo and Paris Commissions (OSPAR) require reporting of annual sediment fluxes. While they may be measured in large rivers, sediment flux is rarely measured in smaller rivers. Measurements of sediment transport at a national scale can be also challenging and therefore, sediment yield models are often utilised by water resource managers for the predictions of sediment yields in the ungauged catchments. Regression based models, calibrated to field measurements, can offer an advantage over complex and computational models due to their simplicity, easy access to input data and due to the additional insights into factors controlling sediment export in the study sites. While traditionally calibrated to long-term average values of sediment yields such predictions cannot represent temporal variations. This study addresses this issue in a novel way by taking account of the variation from year to year in hydrological variables in the developed models (using annual mean runoff, annual mean flow, flows exceeded in five percentage of the time (Q5) and seasonal rainfall estimated separately for each year of observations). Other parameters included in the models represent spatial differences influenced by factors such as soil properties (% poorly drained soils and % peaty soils), land-use (% pasture or % arable lands), channel slope (S1085) and drainage network properties (drainage density). Catchment descriptors together with year-specific hydrological variables can explain both spatial differences and inter-annual variability of suspended sediment yields. The methodology is demonstrated by deriving equations from Irish data-sets (compiled in this study) with the best model

  8. Variation in Yield and Physicochemical Quality Traits among Mutants of Japonica Rice Cultivar Wuyujing 3

    Directory of Open Access Journals (Sweden)

    Jose Daniel Abacar

    2016-01-01

    Full Text Available To select elite germplasms, 112 mutants derived from japonica rice cultivar Wuyujing 3 were evaluated. The yield components such as panicle number per square meter, grain number per panicle, and grain weight were measured. The quality traits such as percentage of chalky grains (PCG, brown rice yield (BRY, milled rice yield (MRY, degree of milling (DM, amylose content (AC, protein content (PC, and relationships among traits were inverstigated. Results showed that grain yield ranged from 2.15 to 12.49 t/hm2 with a mean of 6.4 t/hm2 and number of grains per square meter contributed for 94.64% in grain yield variation. For quality traits, all rice mutants had short size (grain length ≤ 5.5 mm and bold shape (grain length to width ratio = 1.10–2.00. Most of rice mutants (87.5% had PCG values below 20%. All mutants had MRY values above 50%, AC values below 20%, and PC values below 10%. Percentage of chalky grains was significantly negatively correlated with MRY and positively correlated with DM. BRY and MRY were significantly negatively correlated with DM. PC was significantly and positively correlated with MRY and negatively correlated with DM, while AC had no significant correlation with these quality traits. It was concluded that there were 25 rice mutants which fulfilled the major requirements of Jiangsu standard japonica rice such as low percentage of chalky grains, low amylose content, optimal protein content, and which could be used as elite germplasms. Thus the mutants identified may lead to significant progress in improvement of rice quality.

  9. Electron thermalization distances and free-ion yields in dielectric fluids: Effect of electron scavengers

    International Nuclear Information System (INIS)

    Gee, N.; Freeman, G.R.

    1985-01-01

    Free-ion yields were measured in isobutane and in solutions containing sulfur hexafluoride, at densities from the liquid at 295 K to the supercritical fluid. A modified Onsager model was used to estimate the most probable thermalization distances b/sub GP/ (GP denotes a Gaussian power-law distribution). The density-normalized distance b/sub GP/d in isobutane increased from 6.3 x 10 -6 kg/m 2 at 295 K to a maximum of 10.5 x 10 -6 kg/m 2 at 395 K, and then decreased to 5.6 x 10 -6 kg/m 2 at 408 K (T/sub c/). The maximum, which is evidence of conduction-band enhancement of b/sub GP/, was suppressed in solutions containing small amounts of SF 6 . The SF 6 captured the electrons while they were still at epithermal energies, and terminated their flight away from their sibling ions. The values of b/sub GP/ and the free-ion yields were thereby decreased

  10. The enhancement of positronium yields by the hydroxide ion in the radiolysis of water

    International Nuclear Information System (INIS)

    Beling, C.D.; Smith, F.A.

    1984-01-01

    Measurements of o-Ps yield and quenching rate have been made at 21 deg C in aqueous solutions of sodium hydroxide up to 8 M. The observed enhancement is considered within the spur model and attributed to the scavenging of H 2 + O by the OH - ion with an estimated scavenging constant K = 0.354 M -1 . By making use of the measured yields of H 2 , OH radical and e - sub(aq) from long time-scale experiments we can estimate the ratio of the reaction rates of an epithermal electron state. The Ps enhancement coefficient may then be related to these reaction rates and the scavenging constant of H 2 + O. The decrease in equivalent conductance with increasing NaOH concentration up to approx. 12 M suggests the importance of associated and dissociated OH - species. When the total NaOH concentrations are re-expressed as concentrations of dissociated OH - ions a linear increase in o-Ps intensity is found. The fitted enhancement coefficient bears excellent agreement with that estimated from the foregoing consideration of reaction rates. Our analysis shows that the relative yields of both Ps and e - sub(aq) should be in agreement. Within experimental error the data from pulse radiolysis shows that this is in fact the case. (author)

  11. Variation for yield, water-use efficiency, and canopy morphology among nine alfalfa germplasms

    International Nuclear Information System (INIS)

    Ray, I.M.; Townsend, M.S.; Henning, J.A.

    1998-01-01

    Alfalfa (Medicago sativa L.) production under irrigated and rainfed conditions may benefit from improvements in water-use efficiency (WUE), the amount of forage and root biomass produced per unit of water transpired. If benefits from improved WUE are to be realized, correlations between important agronomic traits and key physiological traits associated with WUE must be determined. This study characterized variation for dry matter yield, forage maturity, leaf-to-stem ratio (LSR), carbon isotope discrimination (delta), canopy temperature, ash content, and specific leaf mass (SLM) in alfalfa. Associations between traits were also determined. Nine alfalfa germplasms representing eight of the nine historical genetic diversity groups, and a very fall-dormant (VFD) population, were established in seeded, irrigated plots for 2 yr near Las Cruces, NM. Significant variation (P less than or equal to 0.10) was detected for all traits and was greatest for delta and maturity, intermediate for yield, canopy temperature, ash content, and LSR, and least for SLM. The African, Peruvian, and Indian germplasms exhibited a higher delta than either the Turkistan, VFD, M. varia Martyn., or Ladak germplasms. Carbon isotope discrimination was positively correlated with forage yield (r = 0.64; P less than or equal to 0.10; n = 9) and forage maturity (r = 0.66; P less than or equal to 0.05; n = 9). No association was detected between delta and either canopy temperature, ash content, SLM, or LSR. The results indicate that differences in stomatal conductance or photosynthetic capacity exist among the nine populations, and that germplasms with low delta tended to have slower growth and development rates under irrigated conditions. Neither canopy temperature, ash content, nor SLM provided suitable alternate measurements of delta among the nine alfalfa germplasms

  12. Organic SIMS: the influence of time on the ion yield enhancement by silver and gold deposition

    Science.gov (United States)

    Adriaensen, L.; Vangaever, F.; Gijbels, R.

    2004-06-01

    A series of organic dyes and pharmaceuticals was used to study the secondary ion yield enhancement by metal deposition. The molecules were dissolved in methanol and spincasted on silicon substrates. Subsequently, silver or gold was evaporated on the samples to produce a very thin coating. The coated samples, when measured with TOF-SIMS, showed a considerable increase in characteristic secondary ion intensity. Gold-evaporated samples appear to exhibit the highest signal enhancement. These observations apply to organic samples in general, an advantage that allows to use the technique of metal deposition on real-world samples. However, the observed signal increase does not occur at any given moment. The time between metal deposition on the sample surface and the measuring of the sample with TOF-SIMS appears to have an important influence on the enhancement of the secondary ion intensities. In consideration of these observations several experiments were carried out, in which the spincasted samples were measured at different times after sample preparation, i.e., after gold or silver was deposited on the sample surface. The results show that, depending on the sample and the metal deposited, the secondary ion signals reach their maximum at different times. Further study will be necessary to detect the mechanism responsible for the observed enhancement effect.

  13. Reversibility effects in disordered and ordered solids leading to scattered-ion yield enhancements near 1800

    International Nuclear Information System (INIS)

    Appleton, B.R.; Holland, O.W.; Barrett, J.H.

    1981-01-01

    A general review is given of the recently discovered phenomenon of enhanced ion backscattering near 180 0 . Examples of experimental results are presented that illustrate the nature of the enhancement and its basic dependences on angle and depth. It is shown that the various aspects of the effect can be reproduced by computer simulations that include the effects of trajectory reversibility, nuclear recoils and detector depth resolution. Measured and calculated results are given that illustrate the dependences of the enhancement on ion and target parameters. Results are presented of the enhancement observed in amorphous Ge and in single crystal of Ge rotated to create a reference spectrum. The enhancement is greater for the rotating crystal case demonstrating crystalline effects on the enhancement. Also presented are some results for the enhancement of the surface yield in a channeling direction of a crystal in the 180 0 geometry; possible application for surface studies is discussed. (orig.)

  14. A simple theoretical approach to determine relative ion yield (RIY) in glow discharge mass spectrometry (GDMS)

    Energy Technology Data Exchange (ETDEWEB)

    Born, Sabine [Degussa AG, Hanau (Germany); Matsunami, Noriaki [Nagoya Univ. (Japan). Faculty of Engineering; Tawara, Hiroyuki [National Inst. for Fusion Science, Toki, Gifu (Japan)

    2000-01-01

    Direct current glow discharge mass spectrometry (dc-GDMS) has been applied to detect impurities in metals. The aim of this study is to understand quantitatively the processes taking place in GDMS and establish a model to calculate the relative ion yield (RIY), which is inversely proportional to the relative sensitivity factor (RSF), in order to achieve better agreement between the calculated and the experimental RIYs. A comparison is made between the calculated RIY of the present model and the experimental RIY, and also with other models. (author)

  15. Determining the sputter yields of molybdenum in low-index crystal planes via electron backscattered diffraction, focused ion beam and atomic force microscope

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H.S., E-mail: 160184@mail.csc.com.tw [New Materials Research and Development Department, China Steel Corporation, 1 Chung Kang Road, Hsiao Kang, Kaohsiung 812, Taiwan, ROC (China); Chiu, C.H.; Hong, I.T.; Tung, H.C. [New Materials Research and Development Department, China Steel Corporation, 1 Chung Kang Road, Hsiao Kang, Kaohsiung 812, Taiwan, ROC (China); Chien, F.S.-S. [Department of Physics, Tunghai University, 1727, Sec. 4, Xitun Dist., Taiwan Boulevard, Taichung 407, Taiwan, ROC (China)

    2013-09-15

    Previous literature has used several monocrystalline sputtering targets with various crystalline planes, respectively, to investigate the variations of the sputter yield of materials in different crystalline orientations. This study presents a method to measure the sputtered yields of Mo for the three low-index planes (100), (110), and (111), through using an easily made polycrystalline target. The procedure was firstly to use electron backscattered diffraction to identify the grain positions of the three crystalline planes, and then use a focused ion beam to perform the micro-milling of each identified grain, and finally the sputter yields were calculated from the removed volumes, which were measured by atomic force microscope. Experimental results showed that the sputter yield of the primary orientations for Mo varied as Y{sub (110)} > Y{sub (100)} > Y{sub (111)}, coincidental with the ranking of their planar atomic packing densities. The concept of transparency of ion in the crystalline substance was applied to elucidate these results. In addition, the result of (110) orientation exhibiting higher sputter yield is helpful for us to develop a Mo target with a higher deposition rate for use in industry. By changing the deformation process from straight rolling to cross rolling, the (110) texture intensity of the Mo target was significantly improved, and thus enhanced the deposition rate. - Highlights: • We used EBSD, FIB and AFM to measure the sputter yields of Mo in low-index planes. • The sputter yield of the primary orientations for Mo varied as Y{sub (110)} > Y{sub (100)} > Y{sub (111)}. • The transparency of ion was used to elucidate the differences in the sputter yield. • We improved the sputter rate of polycrystalline Mo target by adjusting its texture.

  16. Comparison of Regression Techniques to Predict Response of Oilseed Rape Yield to Variation in Climatic Conditions in Denmark

    DEFF Research Database (Denmark)

    Sharif, Behzad; Makowski, David; Plauborg, Finn

    2017-01-01

    Statistical regression models represent alternatives to process-based dynamic models for predicting the response of crop yields to variation in climatic conditions. Regression models can be used to quantify the effect of change in temperature and precipitation on yields. However, it is difficult ...

  17. From field to region yield predictions in response to pedo-climatic variations in Eastern Canada

    Science.gov (United States)

    JÉGO, G.; Pattey, E.; Liu, J.

    2013-12-01

    The increase in global population coupled with new pressures to produce energy and bioproducts from agricultural land requires an increase in crop productivity. However, the influence of climate and soil variations on crop production and environmental performance is not fully understood and accounted for to define more sustainable and economical management strategies. Regional crop modeling can be a great tool for understanding the impact of climate variations on crop production, for planning grain handling and for assessing the impact of agriculture on the environment, but it is often limited by the availability of input data. The STICS ("Simulateur mulTIdisciplinaire pour les Cultures Standard") crop model, developed by INRA (France) is a functional crop model which has a built-in module to optimize several input parameters by minimizing the difference between calculated and measured output variables, such as Leaf Area Index (LAI). STICS crop model was adapted to the short growing season of the Mixedwood Plains Ecozone using field experiments results, to predict biomass and yield of soybean, spring wheat and corn. To minimize the numbers of inference required for regional applications, 'generic' cultivars rather than specific ones have been calibrated in STICS. After the calibration of several model parameters, the root mean square error (RMSE) of yield and biomass predictions ranged from 10% to 30% for the three crops. A bit more scattering was obtained for LAI (20%variations. Using RS data to re-initialize input parameters that are not readily available (e.g. seeding date) is considered an effective way

  18. Revisiting the total ion yield x-ray absorption spectra of liquid water microjets

    International Nuclear Information System (INIS)

    Saykally, Richard J; Cappa, Chris D.; Smith, Jared D.; Wilson, Kevin R.; Saykally, Richard J.

    2008-01-01

    Measurements of the total ion yield (TIY) x-ray absorption spectrum (XAS) of liquid water by Wilson et al. (2002 J. Phys.: Condens. Matter 14 L221 and 2001 J. Phys. Chem. B 105 3346) have been revisited in light of new experimental and theoretical efforts by our group. Previously, the TIY spectrum was interpreted as a distinct measure of the electronic structure of the liquid water surface. However, our new results indicate that the previously obtained spectrum may have suffered from as yet unidentified experimental artifacts. Although computational results indicate that the liquid water surface should exhibit a TIY-XAS that is fundamentally distinguishable from the bulk liquid XAS, the new experimental results suggest that the observable TIY-XAS is actually nearly identical in appearance to the total electron yield (TEY-)XAS, which is a bulk probe. This surprising similarity between the observed TIY-XAS and TEY-XAS likely results from large contributions from x-ray induced electron stimulated desorption of ions, and does not necessarily indicate that the electronic structure of the bulk liquid and liquid surface are identical

  19. Analysis of the thermal profiles and the charcoal gravimetric yield in three variations of rectangular brick

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Rogerio Lima Mota de; Alves Junior, Edson; Mulina, Bruno Henrique Oliveira; Borges, Valerio Luiz; Carvalho, Solidonio Rodrigues de [Federal University of Uberlandia - UFU, MG (Brazil). School of Mechanical Engineering - FEMEC], e-mails: rogerio@mecanica.ufu.br, edson@mec.ufu.br, vlborges@mecanica.ufu.br, srcarvalho@mecanica.ufu.br

    2010-07-01

    Charcoal assumes a major role in Brazilian economic scenario. The procedure for obtaining charcoal consists in carbonization of wood at certain specific temperatures in kilns. This ancient process has a few joined technologies and the kilns for such practice do not have any control instruments, in their great majority, becoming dependent on the ability of its operators. However, in recent decades several studies have been developed to improve the practice as well as the equipment that involve and control the stages of charcoal production. In this sense, this work proposes the analysis of the thermal profiles and the gravimetric yield in three variations of a rectangular brick kiln called RAC220: traditional (without any type of instrumentation), instrumented with thermal sensors (RTD PT100) and adapted with gasifier. The goal is to correlate temperature, gravimetric yield and quality of the produced charcoal. Immediate analyses were performed to determine the amount of fixed carbon, volatile gases and ashes contents in charcoal. Through such measurement procedures, together with statistical analysis, the aim is to identify an important tool to reduce the time of charcoal production and also contributes to minimize losses and to increase the thermal efficiency of the production process. (author)

  20. Salt sensitivity in chickpea (Cicer arietinum L.): ions in reproductive tissues and yield components in contrasting genotypes.

    Science.gov (United States)

    Kotula, Lukasz; Khan, Hammad A; Quealy, John; Turner, Neil C; Vadez, Vincent; Siddique, Kadambot H M; Clode, Peta L; Colmer, Timothy D

    2015-08-01

    The reproductive phase in chickpea (Cicer arietinum L.) is affected by salinity, but little is known about the underlying cause. We investigated whether high concentrations of Na(+) and Cl(-) in the reproductive structures influence reproductive processes. Chickpea genotypes contrasting in tolerance were subjected to 0, 35 or 50 mm NaCl applied to soil in pots. Flower production and abortion, pod number, percentage of empty pods, seed number and size were evaluated. The concentrations of Na(+) , K(+) and Cl(-) were measured in various plant tissues and, using X-ray microanalysis, in specific cells of developing reproductive structures. Genotypic variation in reproductive success measured as seed yield in saline conditions was associated with better maintenance of flower production and higher numbers of filled pods (and thus seed number), whereas seed size decreased in all genotypes. Despite the variation in reproductive success, the accumulation of Na(+) and Cl(-) in the early reproductive tissues of developing pods did not differ between a tolerant (Genesis836) and a sensitive (Rupali) genotype. Similarly, salinity tolerance was not associated with the accumulation of salt ions in leaves at the time of reproduction or in seeds at maturity. © 2015 John Wiley & Sons Ltd.

  1. Composition and energy spectrum variations of auroral ions

    International Nuclear Information System (INIS)

    Lynch, J.; Leach, R.; Pulliam, D.; Scherb, F.

    1977-01-01

    We have detected H + ,O + , and He ++ ions with E/q up to 20 keV/charge in a hydrogen aurora over Churchill, Manitoba, during the flight of a Javelin sounding rocket on February 11, 1975, We observed several examples of different types of ion events. One type consisted of bursts of H + and O + ions which arrived simultaneously at all energies within the range of the E/q analyzer. These events were apparently of local origin (distance + ions (O + /H + approximately-greater-than30%). A second type of event consisted of bursts of enhanced H + counting rates but no O + ions. The dispersion in time of the energy spectrum was consistent with an injection and acceleration site located at about 20 R/sub E/ from the earth. An enhancement of the He ++ counting rates was associated with these events, but the He ++ data are of limited statistical significance. A third type of event, consisting of short bursts of H + ions with wide energy spreads, was observed in association with an event in which the energy of the H + ions showed time dispersion. We interpret these short H + bursts as due to ions trapped in traveling waves generated by an explosive injection of plasma in the earth's magnetotail

  2. Combining satellite remote sensing and surveys to understand persistent yield variation--- a case study in North China Plain

    Science.gov (United States)

    Zhao, Y.; Lobell, D. B.; Chen, X.

    2015-12-01

    A large gap between maize yields on average farmers' fields and the highest yields achieved by either experiment or farmers is typical throughout the developing world, including in the North China Plain (NCP). This maize yield gap as identified by previous studies indicates large opportunities for raising yield by improving agronomy. Quzhou county is typical of the winter-wheat summer-maize system in NCP where the average plot size is as small as 0.25 hectares. To analyze this cropping system amidst the challenge of substantial heterogeneity, we identified fields that were either persistently higher or lower yielding according to the remote sensing yield estimates, and then conducted detailed field surveys. We found irrigation facility to be a major constraint to yield both in terms of irrigation water quality and farmers' access to wells. In total, improving the access to unsalty water would be associated with a 0.32t/ha (4.2%) increase in multi-year average yield. In addition, farmers' method of choosing cultivar, which likely relates to their overall knowledge level, significantly explained yield variation. In particular, those choosing cultivars according to technician advice, personal experiences and high yielding neighbors' advice had on average higher yield than farmers that either followed seed sellers' advice or collectively purchased seeds. Overall, the study presents a generalizable methodology of assessing yield gap as well as its persistent factors using a combination of satellite and survey data.

  3. Energy dependence of sputtering yields of Be, Be-C and Be-W films by Be{sup +}-ions

    Energy Technology Data Exchange (ETDEWEB)

    Korshunov, S.N.; Guseva, M.I.; Gureev, V.M.; Neumoin, V.E.; Stoljarova, V.G. [Russian Research Center Kurchatov Inst., Moscow (Russian Federation)

    1998-01-01

    The energy dependence measurements of Be, Be-C and Be-W deposited layer sputtering yields by Be{sup +}-ions were performed. The ion energy was varied in the range (0.3-5.0) keV. The temperature in the process of irradiation was sustained at the level of 670 K. The mixed layers were prepared by simultaneous sputtering of pair targets, Be and C, Be and W, and Be-targets with Ar{sup +}- and Be{sup +}-ions and codeposition of the sputtered atoms on silicon collectors The codeposited layer thickness was changed in the range of (500-1000) nm. The content of oxigen in the Be, Be-C, Be-W deposited layers did not exceed 20 at.%. The mixed layer sputtering yields were compared with the experimental and calculated data, obtained for the self-sputtering yields of beryllium and carbon. It was found that the sputtering yields of the Be-C and Be deposited layers by Be{sup +}-ions in the energy range (0.3-5.0) keV are within the range between the corresponding self-sputtering yields for Be and C. The sputtering yields for the mixture Be-W are close to the corresponding self-sputtering yields of beryllium. (author)

  4. Total yield and escape depth of electrons from heavy ion solid interactions

    International Nuclear Information System (INIS)

    Frischkorn, H.J.; Burkhard, M.; Groenveld, K.O.; Hofmann, D.; Koschar, P.; Latz, R.; Schader, J.

    1983-01-01

    At high projectile energies ( aboutMeV/U) several mechanisms for electron production are discussed as e.g. direct ionization collisions, recoil particle cascades, collective electron emission. Results are presented of total electron yield (#betta#) measurements over a wide projectile energy E /SUB p/ range (40 keV/U< E /SUB p/ /M <12 MeV/U) and a wide projectile Z /SUB p/ range (1<2 /SUB p-/ <92) of both monoionic and molecular projectiles and of different target thicknesses. From the target thickness dependence of #betta# the mean free path lambda of electrons in carbon can be calculated. The data are discussed in the frame of current theories. Significant deviations from calculated values and predicted dependencies are found, in particular for projectile velocities v /SUB p/ close to the Fermi velocity v /SUB F/ of target electrons and for molecular projectile ions

  5. A new ion source for fission-yield measurements of rare-earth isotopes

    International Nuclear Information System (INIS)

    Pilzer, E.H.; Engler, G.

    1987-01-01

    A new integrated target-ion source for fission-yield measurements of rare-earth isotopes has been developed for the Soreq on-line isotope separator (SOLIS). The source is heated by electron bombardment to a temperature of 2400 0 C and ionization takes place in a rhenium hot cavity. To overcome the problem of impurities which reduce the ionization efficiency, a ZrC disk was inserted in the cavity. Calculations show that because of its high thermionic emission, ZrC enhances ionization performance considerably. For example, in the presence of 10 -5 mbar of cesium impurity, the ionization efficiency of a rhenium hot cavity for the rare-earth terbium is 6%. However, with a ZrC disk, the efficiency increases to 97%. (orig.)

  6. Root growth, soil water variation, and grain yield response of winter wheat to supplemental irrigation

    Directory of Open Access Journals (Sweden)

    Jianguo Man

    2016-04-01

    Full Text Available Water shortage threatens agricultural sustainability in the Huang-Huai-Hai Plain of China. Thus, we investigated the effect of supplemental irrigation (SI on the root growth, soil water variation, and grain yield of winter wheat in this region by measuring the moisture content in different soil layers. Prior to SI, the soil water content (SWC at given soil depths was monitored to calculate amount of irritation water that can rehydrate the soil to target SWC. The SWC before SI was monitored to depths of 20, 40, and 60 cm in treatments of W20, W40, and W60, respectively. Rainfed treatment with no irrigation as the control (W0. The mean root weight density (RWD, triphenyl tetrazolium chloride reduction activity (TTC reduction activity, soluble protein (SP concentrations as well as catalase (CAT, and superoxide dismutase (SOD activities in W40 and W60 treatments were significantly higher than those in W20. The RWD in 60–100 cm soil layers and the root activity, SP concentrations, CAT and SOD activities in 40–60 cm soil layers in W40 treatment were significantly higher than those in W20 and W60. W40 treatment is characterized by higher SWC in the upper soil layers but lower SWC in the 60–100-cm soil layers during grain filling. The soil water consumption (SWU in the 60–100 cm soil layers from anthesis after SI to maturity was the highest in W40. The grain yield, water use efficiency (WUE, and irrigation water productivity were the highest in W40, with corresponding mean values of 9169 kg ha−1, 20.8 kg ha−1 mm−1, and 35.5 kg ha−1 mm−1. The RWD, root activities, SP concentrations, CAT and SOD activities, and SWU were strongly positively correlated with grain yield and WUE. Therefore, the optimum soil layer for SI of winter wheat after jointing is 0–40 cm.

  7. VARIATION IN GRAIN YIELD, BIOMASS AND GRAIN NUMBER OF BARLEY UNDER DROUGHT

    Directory of Open Access Journals (Sweden)

    Cándido López-Castañeda

    2011-08-01

    Full Text Available Variability in grain yield (GY, aerial biomass (BM and number of grains m-2 (G M-2 in F6 lines and commercial varieties of barley was studied, and the relationship among these characters in full-irrigation (FI, drought (D and rain-fed (RF conditions was determined. Variation in GY, BM and G M-2 among all genotypes, between F6 lines and varieties, and among genotypes of F6 lines and varieties was significant in all the three soil moisture environments. GY, BM and G M-2 in FI were 23, 14 and 21 % greater than the average of the three soil moisture environments; GY, BM and G M-2 in RF were 21, 16 y 24 % lower than this average. F6 lines produced greater GY (380 g m-2, BM (1027 g m-2 and G M-2 (8641 than the commercial varieties (GY=290 g m-2; BM=726 g m-2 y G M-2=7463 in average of the three environments. GY was positive and significantly associated with BM and G M-2; BM and G M-2 were also associated. GY could be improved in either FI, D or RF environments by selecting genotypes with a greater BM and G M-2 or both of them.

  8. Correlation of the neutron yield from the plasma focus upon variations in the magnetic field energy of the discharge circuit

    Science.gov (United States)

    Ablesimov, V. E.; Dolin, Yu. N.; Kalinychev, A. E.; Tsibikov, Z. S.

    2017-10-01

    The relation between neutron yield Y and magnetic field energy variations Δ W in the discharge circuit has been studied for a Mather-type plasma-focus camera. The activation technique (activation of silver isotopes) has been used to measure the integral yield of DD neutrons from the source. The time dependence of the neutron yield has been recorded by scintillation detectors. For the device used in the investigations, the neutron yield exhibits a linear dependence on variations in the magnetic field energy Δ W in the discharge circuit at the instant of neutron generation. It is also found that this dependence is related to the initial deuteron pressure in the discharge chamber.

  9. Variation, heritability and association of yield, fiber and morphological traits in a near long staple upland cotton population

    International Nuclear Information System (INIS)

    Shao, D.; Wang, T.; Zhang, H.; Zhu, J.; Tang, F.

    2016-01-01

    Development of near long staple (NLS) cotton germplasm represents a remarkable improvement in fiber properties of upland genotypes without compromising yield potential. This study aimed to evaluate a NLS population for variability in yield, fiber and morphological traits, investigate heritability and genetic advance of these traits, and analyze the interrelationships among them. The NLS lines exhibited large variation for lint yield per hectare and bolls per plant, while little variation for fiber properties. The highest genotypic (GCV) and phenotypic (PCV) coefficient of variation were recorded by lint yield per hectare (25.10%, 23.00%) followed by bolls per plant (18.88%, 16.38%). High heritability along with high response to selection was documented in plant height, bolls per plant and lint yield per hectare indicating that the additive gene function model in the inheritance of these traits and direct selection can be profitably applied on them. Favourable associations were found among fiber length, strength and fineness in this population. It is concluded that there is a great potential in the NSL population for further enhancing yield while maintaining high fiber quality. (author)

  10. Variation in Yield and Physicochemical Quality Traits among Mutants of Japonica Rice Cultivar Wuyujing 3

    OpenAIRE

    Abacar, Jose Daniel; Zhao-miao, Lin; Xin-cheng, Zhang; Cheng-qiang, Ding; She, Tang; Zheng-hui, Liu; Shao-hua, Wang; Yan-feng, Ding

    2016-01-01

    To select elite germplasms, 112 mutants derived from japonica rice cultivar Wuyujing 3 were evaluated. The yield components such as panicle number per square meter, grain number per panicle, and grain weight were measured. The quality traits such as percentage of chalky grains (PCG), brown rice yield (BRY), milled rice yield (MRY), degree of milling (DM), amylose content (AC), protein content (PC), and relationships among traits were inverstigated. Results showed that grain yield ranged from ...

  11. Influence of the pH on molecular hydrogen primary yields in He{sup 2+} ion tracks in liquid water. A Monte Carlo study

    Energy Technology Data Exchange (ETDEWEB)

    Cobut, Vincent [Departement de Chimie, Universite de Cergy-Pontoise, 5 Mail Gay-Lussac, Neuville/Oise, 95031 Cergy-Pontoise Cedex (France)]. E-mail: vincent.cobut@chim.u-cergy.fr; Corbel, Catherine [CEA-Saclay, DSM/DRECAM/SCM/Laboratoire de Radiolyse, Bat. 546, Piece 5, 91191 Gif-sur-Yvette Cedex (France); Patau, Jean Paul [Faculte de Pharmacie, Universite Paul-Sabatier, 35 chemin des Maraichers, 31062 Toulouse Cedex 4 (France)

    2005-02-01

    Monte Carlo calculations are performed to investigate how the acidity of aqueous solutions at room temperature affects the molecular hydrogen (H{sub 2}) yield as a function of time in 20 MeV-He{sup 2+} ion track segments. For pH values varying from 1 to 13, the time dependence of the calculated yields is nearly independent of pH in the time range 10{sup -12}-10{sup -8} s and only weakly dependent in the time range 10{sup -8}-10{sup -6} s. To understand this behaviour, the kinetic mechanisms governing H{sub 2} formation are examined as a function of time. It is found that the main reactions responsible for the H{sub 2} yield as a function of time are strongly pH-dependent at low and high pH values. The pH-dependences of the reaction yields are however such that the variations in the yields compensate each other. This is why the time dependence of the H{sub 2} yield is only weakly pH-dependent.

  12. Ion-stimulated gas desorption yields of coated (Au, Ag, Pd) stainless steel vacuum chambers irradiated with 4.2 MeV/u lead ions

    CERN Document Server

    Mahner, E; Küchler, D; Malabaila, M; Taborelli, M

    2005-01-01

    The ion-induced desorption experiment, installed in the CERN Heavy Ion Accelerator (LINAC 3), has been used to measure molecular desorption yields for 4.2 MeV/u lead ions impacting on different accelerator-type vacuum chambers. In order to study the effect of the surface oxide layer on the gas desorption, gold-, silver-, and palladium-coated 316LN stainless steel chambers and similarly prepared samples were tested for desorption at LINAC 3 and analysed for chemical composition by X-ray Photoemission Spectroscopy (XPS). The large effective desorption yield of 2 x 10**4 molecules/ion, previously measured for uncoated, vacuum fired stainless steel, was reduced after noble metal coating by up to 2 orders of magnitude. In addition, the effectiveness of beam scrubbing with heavy ions and the consequence of a subsequent venting on the desorption yields of a beam-scrubbed vacuum chamber are described. Practical consequences for the vacuum system of the future Low Energy Ion Ring (LEIR) are discussed.

  13. An investigation on the mechanism of sublimed DHB matrix on molecular ion yields in SIMS imaging of brain tissue.

    Science.gov (United States)

    Dowlatshahi Pour, Masoumeh; Malmberg, Per; Ewing, Andrew

    2016-05-01

    We have characterized the use of sublimation to deposit matrix-assisted laser desorption/ionization (MALDI) matrices in secondary ion mass spectrometry (SIMS) analysis, i.e. matrix-enhanced SIMS (ME-SIMS), a common surface modification method to enhance sensitivity for larger molecules and to increase the production of intact molecular ions. We use sublimation to apply a thin layer of a conventional MALDI matrix, 2,5-dihydroxybenzoic acid (DHB), onto rat brain cerebellum tissue to show how this technique can be used to enhance molecular yields in SIMS while still retaining a lateral resolution around 2 μm and also to investigate the mechanism of this enhancement. The results here illustrate that cholesterol, which is a dominant lipid species in the brain, is decreased on the tissue surface after deposition of matrix, particularly in white matter. The decrease of cholesterol is followed by an increased ion yield of several other lipid species. Depth profiling of the sublimed rat brain reveals that the lipid species are de facto extracted by the DHB matrix and concentrated in the top most layers of the sublimed matrix. This extraction/concentration of lipids directly leads to an increase of higher mass lipid ion yield. It is also possible that the decrease of cholesterol decreases the potential suppression of ion yield caused by cholesterol migration to the tissue surface. This result provides us with significant insights into the possible mechanisms involved when using sublimation to deposit this matrix in ME-SIMS.

  14. The nuclear equation of state in effective relativistic field theories and pion yields in heavy-ion collisions

    International Nuclear Information System (INIS)

    Schoenhofen, M.; Cubero, M.; Gering, M.; Sambataro, M.; Feldmeier, H.; Noerenberg, W.

    1989-06-01

    Within the framework of relativistic field theory for nucleons, deltas, scalar and vector mesons, a systematic study of the nuclear equation of state and its relation to pion yields in heavy-ion collisions is presented. Not the compressibility but the effective nucleon mass at normal nuclear density turns out to be the most sensitive parameter. Effects from vaccum fluctuations are well modelled within the mean-field no-sea approximation by self-interaction terms for the scalar meson field. Incomplete thermalization in the fireball may be the reason for the low pion yields observed in heavy-ion collisions. (orig.)

  15. Projectile- and charge-state-dependent electron yields from ion penetration of solids as a probe of preequilibrium stopping power

    DEFF Research Database (Denmark)

    Rothard, H.; Schou, Jørgen; Groeneveld, K.-O.

    1992-01-01

    Kinetic electron-emission yields gamma from swift ion penetration of solids are proportional to the (electronic) stopping power gamma approximately Beta-S*, if the preequilibrium evolution of the charge and excitation states of the positively charged ions is taken into account. We show...... by investigating the "transport factor" beta, the energy spectrum of directly ejected recoil electrons and the evolution of ionic charge state inside solids. Estimates of the energy-loss fraction leading to electron emission and the effective charges of the ions near the surface allow a quantitative description...

  16. Coordination variation of hydrated Cu2+/Br1− ions traversing the interfacial water in mesopores

    Directory of Open Access Journals (Sweden)

    Q. Wang

    2012-06-01

    Full Text Available Resolution of the atomistic and electronic details about the coordination structure variation of hydrated ions in the interfacial water is still a tough challenge, which is, however, essentially important for the understanding of ion adsorption, permeation and other similar processes in aqueous solutions. Here we report the tracing of coordination structure variation for hydrated Cu2+/Br1- ions traversing the interfacial water in Vycor mesopores (ϕ = 7.6 nm by employing both X-ray absorption near edge structure and extended X-ray absorption fine structure spectroscopies. By controlled desorption/adsorption of water, the filling fraction of the mesopores, thus the water layer thickness, can be adjusted, which in turn effects the variation of coordination structure of the ions therein. It is found that both Cu2+ and Br1- ions prefer staying exclusively in the core water, and in this circumstance no ion pairs have been detected in the solution of concentrations up to 1.0 M. Following capillary decondensation occurring at a filling fraction of ∼35% which corresponds to a water layer of about three monolayers, Br1- ions begin immediately to reconstruct their first coordination shell, characterized by ionic dehydration, shrinkage of ion-water bond length, and formation of ion pairs. In contrast, Cu2+ ions can retain a bulk-like coordination structure till being driven to bond directly to the pore surface when the filling fraction is below 20%. At the final stage of dehydration via thermal vacuum treatment at 110°C, Cu2+ ions can be completely reduced to the Cu1+ state, and recover at room temperature only when the filling fraction is above 14%. These results may be inspirable for the investigation of similar problems concerning hydrated ions in water solution under different confining conditions.

  17. Estimating the responses of winter wheat yields to moisture variations in the past 35 years in Jiangsu Province of China.

    Science.gov (United States)

    Xu, Xiangying; Gao, Ping; Zhu, Xinkai; Guo, Wenshan; Ding, Jinfeng; Li, Chunyan

    2018-01-01

    Jiangsu is an important agricultural province in China. Winter wheat, as the second major grain crop in the province, is greatly affected by moisture variations. The objective of this study was to investigate whether there were significant trends in changes in the moisture conditions during wheat growing seasons over the past decades and how the wheat yields responded to different moisture levels by means of a popular drought index, the Standardized Precipitation Evapotranspiration Index (SPEI). The study started with a trend analysis and quantification of the moisture conditions with the Mann-Kendall test and Sen's Slope method, respectively. Then, correlation analysis was carried out to determine the relationship between de-trended wheat yields and multi-scalar SPEI. Finally, a multivariate panel regression model was established to reveal the quantitative yield responses to moisture variations. The results showed that the moisture conditions in Jiangsu were generally at a normal level, but this century appeared slightly drier in because of the relatively high temperatures. There was a significant correlation between short time scale SPEI values and wheat yields. Among the three critical stages of wheat development, the SPEI values in the late growth stage (April-June) had a closer linkage to the yields than in the seedling stage (October-November) and the over-wintering stage (December-February). Moreover, the yield responses displayed an asymmetric characteristic, namely, moisture excess led to higher yield losses compared to moisture deficit in this region. The maximum yield increment could be obtained under the moisture level of slight drought according to the 3-month SPEI at the late growth stage, while extreme wetting resulted in the most severe yield losses. The moisture conditions in the first 15 years of the 21st century were more favorable than in the last 20 years of the 20th century for wheat production in Jiangsu.

  18. Estimating the responses of winter wheat yields to moisture variations in the past 35 years in Jiangsu Province of China.

    Directory of Open Access Journals (Sweden)

    Xiangying Xu

    Full Text Available Jiangsu is an important agricultural province in China. Winter wheat, as the second major grain crop in the province, is greatly affected by moisture variations. The objective of this study was to investigate whether there were significant trends in changes in the moisture conditions during wheat growing seasons over the past decades and how the wheat yields responded to different moisture levels by means of a popular drought index, the Standardized Precipitation Evapotranspiration Index (SPEI. The study started with a trend analysis and quantification of the moisture conditions with the Mann-Kendall test and Sen's Slope method, respectively. Then, correlation analysis was carried out to determine the relationship between de-trended wheat yields and multi-scalar SPEI. Finally, a multivariate panel regression model was established to reveal the quantitative yield responses to moisture variations. The results showed that the moisture conditions in Jiangsu were generally at a normal level, but this century appeared slightly drier in because of the relatively high temperatures. There was a significant correlation between short time scale SPEI values and wheat yields. Among the three critical stages of wheat development, the SPEI values in the late growth stage (April-June had a closer linkage to the yields than in the seedling stage (October-November and the over-wintering stage (December-February. Moreover, the yield responses displayed an asymmetric characteristic, namely, moisture excess led to higher yield losses compared to moisture deficit in this region. The maximum yield increment could be obtained under the moisture level of slight drought according to the 3-month SPEI at the late growth stage, while extreme wetting resulted in the most severe yield losses. The moisture conditions in the first 15 years of the 21st century were more favorable than in the last 20 years of the 20th century for wheat production in Jiangsu.

  19. The Space-Time Variation of Global Crop Yields, Detecting Simultaneous Outliers and Identifying the Teleconnections with Climatic Patterns

    Science.gov (United States)

    Najafi, E.; Devineni, N.; Pal, I.; Khanbilvardi, R.

    2017-12-01

    An understanding of the climate factors that influence the space-time variability of crop yields is important for food security purposes and can help us predict global food availability. In this study, we address how the crop yield trends of countries globally were related to each other during the last several decades and the main climatic variables that triggered high/low crop yields simultaneously across the world. Robust Principal Component Analysis (rPCA) is used to identify the primary modes of variation in wheat, maize, sorghum, rice, soybeans, and barley yields. Relations between these modes of variability and important climatic variables, especially anomalous sea surface temperature (SSTa), are examined from 1964 to 2010. rPCA is also used to identify simultaneous outliers in each year, i.e. systematic high/low crop yields across the globe. The results demonstrated spatiotemporal patterns of these crop yields and the climate-related events that caused them as well as the connection of outliers with weather extremes. We find that among climatic variables, SST has had the most impact on creating simultaneous crop yields variability and yield outliers in many countries. An understanding of this phenomenon can benefit global crop trade networks.

  20. Hydroxyl radical yields in the tracks of high energy 13C6+ and 36Ar18+ ions in liquid water

    International Nuclear Information System (INIS)

    Baldacchino, G.; Vigneron, G.; Renault, J.P.; Le Caer, S.; Pin, S.; Mialocq, J.-C.; Balanzat, E.; Bouffard, S.

    2006-01-01

    This article reports the determination of the OH · radiolytic yields in water irradiated by high energy C 6+ and Ar 18+ ions with LET values of 32 ± 2 and 280 ± 10 eV nm -1 . The time evolution of the yields between 9 x 10 -11 and 9 x 10 -8 s was deduced using the scavenging method with SCN - and Br - and pulse radiolysis with pulses of 5 and 10 μs. The thiocyanate chemical system is less affected with the local high dose rates specific to the high LET particles than the bromide system. At 32 eV nm -1 with C 6+ ions, G(OH · ) reaches a maximum of 1.5 x 10 -7 mol J -1 at 1 ns and decreases at earlier times. With Ar 18+ ions of 280 eV nm -1 G(OH · ) is always increasing at early times up to 1.6 x 10 -7 mol J -1 at 9 x 10 -11 s. In this case the evolution of the hydroxyl radical yields agrees with the high local concentrations obtained with Ar 18+ and C 6+ ions and depicted in recent literature with the yields of the hydrated electron in the ns range

  1. Variation in growth, physiology, and yield of six sugarcane cultivars from across the globe in Florida

    Science.gov (United States)

    Evaluation of sugarcane cultivars with diverse genetic background under similar location can help in better understanding cultivar response to environment and in identifying various physiological traits that could lead to improved yields. The objective of this study was to evaluate the growth, yield...

  2. Secondary ion yield changes in Si and GaAs due to topography changes during O+2 or Cs+ ion bombardment

    International Nuclear Information System (INIS)

    Stevie, F.A.; Kahora, P.M.; Simons, D.S.; Chi, P.

    1988-01-01

    Changes in secondary ion yields of matrix and dopant species have been correlated with changes in surface topography during O + 2 bombardment of Si and GaAs. In Si, profiles were measured in (100) wafers at 6- and 8-keV impact energy. At 6 keV, a yield increase of about 70% occurred for Si + over a depth range of 2.5 to 3.5 μm, with changes in other species ranging from a decrease of ∼20% for Si + 3 to an increase of more than 25% for O + . The development of a rippled surface topography was observed in scanning electron micrographs over the same depth range. Similar effects occurred over a 3--5 μm depth range for 8-keV ions, and in (111) silicon at a depth of 3 to 4 μm for 6-keV ions. No differences were noted between p- and n-type silicon, or implanted and unimplanted silicon. In GaAs, profiles were measured in (100) wafers at 2.5-, 5.5-, and 8-keV impact energies. At 8 keV, a yield increase of about 70% was found for GaO + in the range 0.6--1.0 μm, with smaller changes for other matrix species. At 5.5 keV, similar effects were observed, but over a depth interval of 0.3 to 0.7 μm. No yield changes were detected at 2.5-keV impact energy. The yield changes at the higher energies were again correlated with the onset of changes in topography. No change in ion yield or surface topography was noted for Cs + bombardment of Si or GaAs. The topography and ion yield changes are affected by the angle of incidence and, for Si, the oxygen coverage. The results show that the practice of normalizing secondary ion mass spectrometry dopant profiles to a matrix signal must be modified for situations where matrix yield changes occur

  3. Statistical Evaluations of Variations in Dairy Cows’ Milk Yields as a Precursor of Earthquakes

    Science.gov (United States)

    Yamauchi, Hiroyuki; Hayakawa, Masashi; Asano, Tomokazu; Ohtani, Nobuyo; Ohta, Mitsuaki

    2017-01-01

    Simple Summary There are many reports of abnormal changes occurring in various natural systems prior to earthquakes. Unusual animal behavior is one of these abnormalities; however, there are few objective indicators and to date, reliability has remained uncertain. We found that milk yields of dairy cows decreased prior to an earthquake in our previous case study. In this study, we examined the reliability of decreases in milk yields as a precursor for earthquakes using long-term observation data. In the results, milk yields decreased approximately three weeks before earthquakes. We have come to the conclusion that dairy cow milk yields have applicability as an objectively observable unusual animal behavior prior to earthquakes, and dairy cows respond to some physical or chemical precursors of earthquakes. Abstract Previous studies have provided quantitative data regarding unusual animal behavior prior to earthquakes; however, few studies include long-term, observational data. Our previous study revealed that the milk yields of dairy cows decreased prior to an extremely large earthquake. To clarify whether the milk yields decrease prior to earthquakes, we examined the relationship between earthquakes of various magnitudes and daily milk yields. The observation period was one year. In the results, cross-correlation analyses revealed a significant negative correlation between earthquake occurrence and milk yields approximately three weeks beforehand. Approximately a week and a half beforehand, a positive correlation was revealed, and the correlation gradually receded to zero as the day of the earthquake approached. Future studies that use data from a longer observation period are needed because this study only considered ten earthquakes and therefore does not have strong statistical power. Additionally, we compared the milk yields with the subionospheric very low frequency/low frequency (VLF/LF) propagation data indicating ionospheric perturbations. The results showed

  4. Ionization of liquid argon by x-rays: effect of density on electron thermalization and free ion yields

    International Nuclear Information System (INIS)

    Huang, S.S.-S.; Gee, N.; Freeman, G.R.

    1991-01-01

    Free ion yields were measured in liquid argon as a function of electric field strength at densities 736-1343 kg/m 3 (temperatures 149-95 K). The field dependence of the yields was parametrized using the extended Onsager and box models. Over the present density range the total ion yield was constant within 1% and was taken as 4.4, the average of earlier values at 87-91 K. The absence of internal vibrational modes in argon makes its electron thermalizing ability smaller than that of methane. The electron thermalization distance b GP in liquid argon is 3-5 times longer than that in liquid methane at a given d/d c (d c = critical fluid density). (author)

  5. Study on mutation breeding and fermentation of antimicrobial lipopeptides yielding bacterium with 20 keV N+ ion beam implantation

    International Nuclear Information System (INIS)

    Fang Chuanji; Lu Zhaoxin; Sun Lijun; Lv Fengxia; Bie Xiaomei

    2006-01-01

    Bacillus amyloliquefaciens ES-2 was implanted with 20 keV N + ion beam to breed mutants of high yield of antimicrobial lipopeptides. The dose effects of the nitrogen ion implantation on the survival and positive mutations rate was studied. The mutant strain designated as B. amyloliquefaciens ES-2-4 showing higher yield of antimicrobial lipopeptides was obtained. The concentration of the lipopeptides in fermentation liquid increased by 15.2% compared with the original strain. The authors also studied the fermentation process between the mutant and the original strain. It indicated that the mutant with shorter lag phase, longer stable phase and higher yield of the lipopeptides, which was suitable for large-scale production. (authors)

  6. Accurate argon cluster-ion sputter yields: Measured yields and effect of the sputter threshold in practical depth-profiling by x-ray photoelectron spectroscopy and secondary ion mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Cumpson, Peter J.; Portoles, Jose F.; Barlow, Anders J.; Sano, Naoko [National EPSRC XPS User' s Service (NEXUS), School of Mechanical and Systems Engineering, Newcastle University, Newcastle upon Tyne, NE1 7RU (United Kingdom)

    2013-09-28

    Argon Gas Cluster-Ion Beam sources are likely to become widely used on x-ray photoelectron spectroscopy and secondary ion mass spectrometry instruments in the next few years. At typical energies used for sputter depth profiling the average argon atom in the cluster has a kinetic energy comparable with the sputter threshold, meaning that for the first time in practical surface analysis a quantitative model of sputter yields near threshold is needed. We develop a simple equation based on a very simple model. Though greatly simplified it is likely to have realistic limiting behaviour and can be made useful for estimating sputter yields by fitting its three parameters to experimental data. We measure argon cluster-ion sputter yield using a quartz crystal microbalance close to the sputter threshold, for silicon dioxide, poly(methyl methacrylate), and polystyrene and (along with data for gold from the existing literature) perform least-squares fits of our new sputter yield equation to this data. The equation performs well, with smaller residuals than for earlier empirical models, but more importantly it is very easy to use in the design and quantification of sputter depth-profiling experiments.

  7. Variation in yield gap induced by nitrogen, phosphorus and potassium fertilizer in North China Plain.

    Directory of Open Access Journals (Sweden)

    Xiaoqin Dai

    Full Text Available A field experiment was conducted under a wheat-maize rotation system from 1990 to 2006 in North China Plain (NCP to determine the effects of N, P and K on yield and yield gap. There were five treatments: NPK, PK, NK, NP and a control. Average wheat and maize yields were the highest in the NPK treatment, followed by those in the NP plots among all treatments. For wheat and maize yield, a significant increasing trend over time was found in the NPK-treated plots and a decreasing trend in the NK-treated plots. In the absence of N or P, wheat and maize yields were significantly lower than those in the NPK treatment. For both crops, the increasing rate of the yield gap was the highest in the P omission plots, i.e., 189.1 kg ha(-1 yr(-1 for wheat and 560.6 kg ha(-1 yr(-1 for maize. The cumulative omission of P fertilizer induced a deficit in the soil available N and extractable P concentrations for maize. The P fertilizer was more pivotal in long-term wheat and maize growth and soil fertility conservation in NCP, although the N fertilizer input was important for both crops growth. The crop response to K fertilizers was much lower than that to N or P fertilizers, but for maize, the cumulative omission of K fertilizer decreased the yield by 26% and increased the yield gap at a rate of 322.7 kg ha(-1 yr(-1. The soil indigenous K supply was not sufficiently high to meet maize K requirement over a long period. The proper application of K fertilizers is necessary for maize production in the region. Thus, the appropriate application of N and P fertilizers for the growth of both crops, while regularly combining K fertilizers for maize growth, is absolutely necessary for sustainable crop production in the NCP.

  8. Variation in yield gap induced by nitrogen, phosphorus and potassium fertilizer in North China Plain.

    Science.gov (United States)

    Dai, Xiaoqin; Ouyang, Zhu; Li, Yunsheng; Wang, Huimin

    2013-01-01

    A field experiment was conducted under a wheat-maize rotation system from 1990 to 2006 in North China Plain (NCP) to determine the effects of N, P and K on yield and yield gap. There were five treatments: NPK, PK, NK, NP and a control. Average wheat and maize yields were the highest in the NPK treatment, followed by those in the NP plots among all treatments. For wheat and maize yield, a significant increasing trend over time was found in the NPK-treated plots and a decreasing trend in the NK-treated plots. In the absence of N or P, wheat and maize yields were significantly lower than those in the NPK treatment. For both crops, the increasing rate of the yield gap was the highest in the P omission plots, i.e., 189.1 kg ha(-1) yr(-1) for wheat and 560.6 kg ha(-1) yr(-1) for maize. The cumulative omission of P fertilizer induced a deficit in the soil available N and extractable P concentrations for maize. The P fertilizer was more pivotal in long-term wheat and maize growth and soil fertility conservation in NCP, although the N fertilizer input was important for both crops growth. The crop response to K fertilizers was much lower than that to N or P fertilizers, but for maize, the cumulative omission of K fertilizer decreased the yield by 26% and increased the yield gap at a rate of 322.7 kg ha(-1) yr(-1). The soil indigenous K supply was not sufficiently high to meet maize K requirement over a long period. The proper application of K fertilizers is necessary for maize production in the region. Thus, the appropriate application of N and P fertilizers for the growth of both crops, while regularly combining K fertilizers for maize growth, is absolutely necessary for sustainable crop production in the NCP.

  9. Inter-annual variations in water yield to lakes in northeastern Alberta: implications for estimating critical loads of acidity

    Directory of Open Access Journals (Sweden)

    Roderick HAZEWINKEL

    2010-08-01

    Full Text Available Stable isotopes of water were applied to estimate water yield to fifty lakes in northeastern Alberta as part of an acid sensitivity study underway since 2002 in the Athabasca Oil Sands Region (AOSR. Herein, we apply site-specific water yields for each lake to calculate critical loads of acidity using water chemistry data and a steady-state water chemistry model. The main goal of this research was to improve site-specific critical load estimates and to understand the sensitivity to hydrologic variability across a Boreal Plains region under significant oil sands development pressure. Overall, catchment water yields were found to vary significantly over the seven year monitoring period, with distinct variations among lakes and between different regions, overprinted by inter-annual climate-driven shifts. Analysis of critical load estimates based on site-specific water yields suggests that caution must be applied to establish hydrologic conditions and define extremes at specific sites in order to protect more sensitive ecosystems. In general, lakes with low (high water yield tended to be more (less acid sensitive but were typically less (more affected by interannual hydrological variations. While it has been customary to use long-term water yields to define a static critical load for lakes, we find that spatial and temporal variability in water yield may limit effectiveness of this type of assessment in areas of the Boreal Plain characterized by heterogeneous runoff and without a long-term lake-gauging network. Implications for predicting acidification risk are discussed for the AOSR.

  10. Plant density-dependent variations in bioactive markers and root yield in Australian-grown Salvia miltiorrhiza Bunge.

    Science.gov (United States)

    Li, Chun Guang; Sheng, Shu Jun; Pang, Edwin C K; May, Brian; Xue, Charlie Chang Li

    2011-04-01

    The plant density-dependent variations in the root yield and content, and the yield of biomarkers in Australian grown Salvia miltiorrhiza Bunge, a commonly used Chinese medicinal herb for the treatment of cardiovascular diseases, were investigated in a field trial involving six different plant densities. The key biomarker compounds cryptotanshinone, tanshinone I, tanshinone IIA, and salvianolic acid B were quantified by a validated RP-HPLC method, and the root yields were determined per plant pair or unit area. There were significant variations (pplant densities. Positive linear correlations were observed between the contents of the three tanshinones, whereas negative linear correlations were revealed between the contents of the tanshinones and salvianolic acid B. The highest root yield per plant pair was achieved when the plants were grown at 45×30 cm or 45×40 cm, whereas the highest root production par unit area was obtained for a plant density of 30×30 cm. The highest contents of the three tanshinones and the most abundant production of these tanshinones per unit area were achieved when the plants were grown at 30×30 cm. However, the highest content of salvianolic acid B was found for a density of 45×40 cm, while its highest yield per unit area was obtained for densities of 30×40 cm or 45×30 cm. The findings suggest that the plant density distinctly affects the root yield and content and the yield of tanshinones and salvianolic acid B in Australian grown S. miltiorrhiza, which may be used as a guide for developing optimal agricultural procedures for cultivating this herb. Copyright © 2011 Verlag Helvetica Chimica Acta AG, Zürich.

  11. X-ray yields from high-energy heavy ions channeled through a crystal: their crystal thickness and projectile dependences

    International Nuclear Information System (INIS)

    Kondo, C.; Takabayashi, Y.; Muranaka, T.; Masugi, S.; Azuma, T.; Komaki, K.; Hatakeyama, A.; Yamazaki, Y.; Takada, E.; Murakami, T.

    2005-01-01

    X-rays emitted from Ar 17+ , Fe 24+ and Kr 35+ ions of about 400 MeV/u transmitting through a thin Si crystal of about 20 μm thickness have been measured in a planar channeling condition and compared with those in a random incident condition. We have found that the X-ray yield from Ar 17+ ions is larger for the channeling condition than for the random incidence, while those from Fe 24+ and Kr 35+ ions are rather smaller. Such tendencies are explained by considering the projectile dependences of excitation and ionization probabilities together with X-ray emission rates. A crude simulation has qualitatively reproduced these experimental results. When the crystal thickness is small, the X-ray yield is smaller in the channeling condition than in the random incident condition, because excitation is depressed. However, for thicker crystals, the X-ray yield is larger, since the survived population of projectile-bound electrons is larger due to small ionization probabilities under the channeling condition. This inversion occurs at a specific crystal thickness depending on projectile species. Whether the thickness of the used crystal is smaller or larger than the inversion thickness determines enhancement or depression of the X-ray yield in the channeling condition

  12. Estimation of variation and correlation analysis for yield components in black currant cultivars

    Directory of Open Access Journals (Sweden)

    Rakonjac Vera

    2015-01-01

    Full Text Available Creating genotypes that will be characterized by high yields, good quality and other favorable agronomic characters is a major objective of most currant breeding programs worldwide. For easier and faster achievement of these goals and identification of superior genotypes suitable for use as parents in future hybridization programs, study of genetic parameters seems to be obligatory. In this regard, the aims of our study were to estimate components of variability and heritability, and do correlation analysis for yield components in order to determine efficient strategies for improving yield in black currant breeding programs. Significant differences between cultivars were established for all studied traits. A high proportion of genotypic variance was found with bush width, no. of shoots per bush, bunch weight and berry weight indicating that genetic improvement for these traits through breeding was achievable. Opposite, seasonal variance was high for bush height, no. of bunch per bush and yield. The high heritability coefficients (0.80-0.94 detected for all traits studied reflect the close agreement between their phenotypic and genotypic values. Also, most pairs of traits were similarly correlated at both phenotypic and genotypic levels. So, yield was significantly and positively correlated with bush height, no of bunch per bush and bunch weight. These results imply a rapid response of black currants to selection. [Projekat Ministarstva nauke Republike Srbije, br. 46013 i FP7 Project AREA 316004

  13. Genetic variations in ARE1 mediate grain yield by modulating nitrogen utilization in rice.

    Science.gov (United States)

    Wang, Qing; Nian, Jinqiang; Xie, Xianzhi; Yu, Hong; Zhang, Jian; Bai, Jiaoteng; Dong, Guojun; Hu, Jiang; Bai, Bo; Chen, Lichao; Xie, Qingjun; Feng, Jian; Yang, Xiaolu; Peng, Juli; Chen, Fan; Qian, Qian; Li, Jiayang; Zuo, Jianru

    2018-02-21

    In crops, nitrogen directly determines productivity and biomass. However, the improvement of nitrogen utilization efficiency (NUE) is still a major challenge in modern agriculture. Here, we report the characterization of are1, a genetic suppressor of a rice fd-gogat mutant defective in nitrogen assimilation. ARE1 is a highly conserved gene, encoding a chloroplast-localized protein. Loss-of-function mutations in ARE1 cause delayed senescence and result in 10-20% grain yield increases, hence enhance NUE under nitrogen-limiting conditions. Analysis of a panel of 2155 rice varieties reveals that 18% indica and 48% aus accessions carry small insertions in the ARE1 promoter, which result in a reduction in ARE1 expression and an increase in grain yield under nitrogen-limiting conditions. We propose that ARE1 is a key mediator of NUE and represents a promising target for breeding high-yield cultivars under nitrogen-limiting condition.

  14. Impact of variation at the FTO locus on milk fat yield in Holstein dairy cattle.

    Science.gov (United States)

    Zielke, Lea G; Bortfeldt, Ralf H; Reissmann, Monika; Tetens, Jens; Thaller, Georg; Brockmann, Gudrun A

    2013-01-01

    This study explores the biological role of the Fat Mass and Obesity associated (FTO) gene locus on milk composition in German Holstein cattle. Since FTO controls energy homeostasis and expenditure and the FTO locus has repeatedly shown association with obesity in human studies, we tested FTO as a candidate gene in particular for milk fat yield, which represents a high amount of energy secreted during lactation. The study was performed on 2,402 bulls and 860 cows where dense milk composition data were available. Genetic information was taken from a 2 Mb region around FTO. Five SNPs and two haplotype blocks in a 725 kb region covering FTO and the neighboring genes RPGRIP1L, U6ATAC, and 5 S rRNA were associated with milk fat yield and also affected protein yield in the same direction. Interestingly, higher frequency SNP alleles and haplotypes within the FTO gene increased milk fat and protein yields by up to 2.8 and 2.2 kg per lactation, respectively, while the most frequent haplotype in the upstream block covering exon 1 of FTO to exon 15 of RPGRIP1L had opposite effects with lower fat and milk yield. Both haplotype blocks were also significant in cows. The loci accounted for about 1% of the corresponding trait variance in the population. The association signals not only provided evidence for at least two causative mutations in the FTO locus with a functional effect on milk but also milk protein yield. The pleiotropic effects suggest a biological function on the usage of energy resources and the control of energy balance rather than directly affecting fat and protein synthesis. The identified effect of the obesity gene locus on milk energy content suggests an impact on infant nutrition by breast feeding in humans.

  15. Impact of variation at the FTO locus on milk fat yield in Holstein dairy cattle.

    Directory of Open Access Journals (Sweden)

    Lea G Zielke

    Full Text Available This study explores the biological role of the Fat Mass and Obesity associated (FTO gene locus on milk composition in German Holstein cattle. Since FTO controls energy homeostasis and expenditure and the FTO locus has repeatedly shown association with obesity in human studies, we tested FTO as a candidate gene in particular for milk fat yield, which represents a high amount of energy secreted during lactation. The study was performed on 2,402 bulls and 860 cows where dense milk composition data were available. Genetic information was taken from a 2 Mb region around FTO. Five SNPs and two haplotype blocks in a 725 kb region covering FTO and the neighboring genes RPGRIP1L, U6ATAC, and 5 S rRNA were associated with milk fat yield and also affected protein yield in the same direction. Interestingly, higher frequency SNP alleles and haplotypes within the FTO gene increased milk fat and protein yields by up to 2.8 and 2.2 kg per lactation, respectively, while the most frequent haplotype in the upstream block covering exon 1 of FTO to exon 15 of RPGRIP1L had opposite effects with lower fat and milk yield. Both haplotype blocks were also significant in cows. The loci accounted for about 1% of the corresponding trait variance in the population. The association signals not only provided evidence for at least two causative mutations in the FTO locus with a functional effect on milk but also milk protein yield. The pleiotropic effects suggest a biological function on the usage of energy resources and the control of energy balance rather than directly affecting fat and protein synthesis. The identified effect of the obesity gene locus on milk energy content suggests an impact on infant nutrition by breast feeding in humans.

  16. Runoff and sediment variation in the areas with high and coarse sediment yield of the middle Yellow River

    Science.gov (United States)

    Zhang, Pan; Yao, Wenyi; Xiao, Peiqing; Sun, Weiying

    2018-02-01

    Massive water and soil conservation works (WSCW) have been conducted in the areas with high and coarse sediment yield of the middle Yellow River since 1982. With the impending effects of climate change, it is necessary to reconsider the effects of WSCW on runoff and sediment variation at decadal and regional scales. Using long-term official and synthesized data, the WSCW impacts on reducing water and soil loss were studied in Sanchuanhe River watershed. Results showed that the sediment and runoff generated from this area showed a decreasing trend in the past 50 years. A great progress has been achieved in erosion control since the 1970s. After the 4 soil and water conservation harnessing stages during the period from 1970 to 2006, the sediment and runoff yield showed decreases with the extension of harnessing. The results revealed that human activities exerted the largest effects on the sediment reduction and explained 66.6% of the variation in the specific sediment yield. The contribution of rainfall variation to runoff reduction was as large as human activities. A great benefit have been obtained in water and soil loss control in this area.

  17. Seasonal variations in furfural yield of some species of coppice and Mediterranean maquis

    Energy Technology Data Exchange (ETDEWEB)

    Vidrich, V.; Cecconi, C.A.; Martini, R.; Pazzagli, G.; Fusi, P.

    1982-01-01

    Studies were made with the object of complete utilization of forest residues. They showed that Quercus cerris, Myrtus species and Phyllirea species from the Maremma region of Tuscany, and Q. pubescens and Rhamnus alaternus from the Montecatini region of the province were suitable for economic exploitation. For all these species, the normal cutting time coincided with the optimum yield of furfural. 11 references.

  18. Secondary-electron yield from Au induced by highly charged Ta ions

    Czech Academy of Sciences Publication Activity Database

    Krása, Josef; Láska, Leoš; Stöckli, M. P.; Fry, D.

    2001-01-01

    Roč. 173, - (2001), s. 281-286 ISSN 0168-583X R&D Projects: GA AV ČR IAA1010819 Institutional research plan: CEZ:AV0Z1010914 Keywords : highly charged ion-surface interaction * ion-induced electron emission * angle impact effect Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.041, year: 2001

  19. Heavy-ion induced desorption yields of amorphous carbon films bombarded with 4.2 MeV/u lead ions

    CERN Document Server

    Mahner, E; Küchler, D; Scrivens, R; Costa Pinto, P; Yin Vallgren, C; Bender, M

    2011-01-01

    During the past decade, intense experimental studies on the heavy-ion induced molecular desorption were performed in several particle accelerator laboratories worldwide in order to understand and overcome large dynamic pressure rises caused by lost beam ions. Different target materials and various coatings were studied for desorption and mitigation techniques were applied to heavy-ion accelerators. For the upgrade of the CERN injector complex, a coating of the Super Proton Synchrotron (SPS) vacuum system with a thin film of amorphous carbon is under study to mitigate the electron cloud effect observed during SPS operation with the nominal proton beam for the Large Hadron Collider (LHC). Since the SPS is also part of the heavy-ion injector chain for LHC, dynamic vacuum studies of amorphous carbon films are important to determine their ion induced desorption yields. At the CERN Heavy Ion Accelerator (LINAC 3), carbon-coated accelerator-type stainless steel vacuum chambers were tested for desorption using 4.2 Me...

  20. Diversity of fields and farmers : explaining yield variations in northern Cameroon

    NARCIS (Netherlands)

    Steenhuijsen Piters, de B.

    1995-01-01

    This research was inspired by the inability of agricultural research to deal adequately with phenomena of variation, diversity and heterogeneity in agriculture. Although these phenomena were observed as long ago as the beginning of this century, they are still causing concern. Until

  1. Anomalous width variation of rarefactive ion acoustic solitary waves in the context of auroral plasmas

    Directory of Open Access Journals (Sweden)

    S. S. Ghosh

    2004-01-01

    Full Text Available The presence of dynamic, large amplitude solitary waves in the auroral regions of space is well known. Since their velocities are of the order of the ion acoustic speed, they may well be considered as being generated from the nonlinear evolution of ion acoustic waves. However, they do not show the expected width-amplitude correlation for K-dV solitons. Recent POLAR observations have actually revealed that the low altitude rarefactive ion acoustic solitary waves are associated with an increase in the width with increasing amplitude. This indicates that a weakly nonlinear theory is not appropriate to describe the solitary structures in the auroral regions. In the present work, a fully nonlinear analysis based on Sagdeev pseudopotential technique has been adopted for both parallel and oblique propagation of rarefactive solitary waves in a two electron temperature multi-ion plasma. The large amplitude solutions have consistently shown an increase in the width with increasing amplitude. The width-amplitude variation profile of obliquely propagating rarefactive solitary waves in a magnetized plasma have been compared with the recent POLAR observations. The width-amplitude variation pattern is found to fit well with the analytical results. It indicates that a fully nonlinear theory of ion acoustic solitary waves may well explain the observed anomalous width variations of large amplitude structures in the auroral region.

  2. The analysis of protein variation of wheat implanted by ion beam

    International Nuclear Information System (INIS)

    Qin Guangyong; Cao Gangqiang; Huo Yuping; Su Mingjie; Zhang Yanfeng; Wang Weidong

    2002-05-01

    Other total DNA was transducted into wheat grain by ion beam. The results show that the protein content of transgenic wheat changes obviously, and two new types with high and low protein content extreme variation are obtained. On the basis of it, we analysed the affection of the ways about transduction on protein content

  3. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    International Nuclear Information System (INIS)

    Mahadtanapuk, S.; Teraarusiri, W.; Phanchaisri, B.; Yu, L.D.; Anuntalabhochai, S.

    2013-01-01

    Highlights: •N-ion beam bombarded Thai jasmine rice seeds to induce mutation. •Mutants with blast-disease resistance and high yield were screened. •Gene involved in the blast-disease resistance was analyzed. •The gene responsible for the resistance was linked to Spotted leaf protein 11. -- Abstract: Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60–80 keV to a beam fluence range of 2 × 10 16 –2 × 10 17 ions/cm 2 . The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 10 6 spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11)

  4. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Mahadtanapuk, S. [School of Agriculture and Natural Resources, University of Phayao, Phayao 56000 (Thailand); Teraarusiri, W. [Central Laboratory, University of Phayao, Phayao 56000 (Thailand); Phanchaisri, B. [Science and Technology Research Institute, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@frnf.science.cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Anuntalabhochai, S., E-mail: burinka@hotmail.com [Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2013-07-15

    Highlights: •N-ion beam bombarded Thai jasmine rice seeds to induce mutation. •Mutants with blast-disease resistance and high yield were screened. •Gene involved in the blast-disease resistance was analyzed. •The gene responsible for the resistance was linked to Spotted leaf protein 11. -- Abstract: Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60–80 keV to a beam fluence range of 2 × 10{sup 16}–2 × 10{sup 17} ions/cm{sup 2}. The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 10{sup 6} spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11)

  5. Molecular dynamics simulations with electronic stopping can reproduce experimental sputtering yields of metals impacted by large cluster ions

    Science.gov (United States)

    Tian, Jiting; Zhou, Wei; Feng, Qijie; Zheng, Jian

    2018-03-01

    An unsolved problem in research of sputtering from metals induced by energetic large cluster ions is that molecular dynamics (MD) simulations often produce sputtering yields much higher than experimental results. Different from the previous simulations considering only elastic atomic interactions (nuclear stopping), here we incorporate inelastic electrons-atoms interactions (electronic stopping, ES) into MD simulations using a friction model. In this way we have simulated continuous 45° impacts of 10-20 keV C60 on a Ag(111) surface, and found that the calculated sputtering yields can be very close to the experimental results when the model parameter is appropriately assigned. Conversely, when we ignore the effect of ES, the yields are much higher, just like the previous studies. We further expand our research to the sputtering of Au induced by continuous keV C60 or Ar100 bombardments, and obtain quite similar results. Our study indicates that the gap between the experimental and the simulated sputtering yields is probably induced by the ignorance of ES in the simulations, and that a careful treatment of this issue is important for simulations of cluster-ion-induced sputtering, especially for those aiming to compare with experiments.

  6. Flow direction variations of low energy ions as measured by the ion electron sensor (IES) flying on board of Rosetta

    Science.gov (United States)

    Szegö, Karoly; Nemeth, Zoltan; Foldy, Lajos; Burch, James L.; Goldstein, Raymond; Mandt, Kathleen; Mokashi, Prachet; Broiles, Tom

    2015-04-01

    : one close to the anti-solar direction, and one perpendicular to it. The occurrence and variations of these directions are still under investigation. A possible cause of the acceleration of low energy ions along the solar wind might be that electrons produced by the ionization of neutrals are immediately picked up by the solar wind generating a polarization electric field that accelerates the ions. This effect is similar to the generation of ionospheric holes at Venus [Hartle and Grebowsky, Adv. Space Res., 4, 1995]. The acceleration perpendicular to the solar wind might be due to the v x B electric field. The variations of the low energy flow direction is analyzed in detail in the presentation.

  7. Impact parameter dependence of the specific entropy and the light particle yield in relativistic heavy ion collisions

    International Nuclear Information System (INIS)

    Gudima, K.K.; Toneev, V.D.

    1986-01-01

    The connection between the fragment yield and the associated specific entropy of particles produced in the course of a relativistic heavy ion collision is studied within the cascade approach. The essential impact parameter dependence of the fragment yield indicates that the specific entropy increases with impact parameter and that the critical density of the system decay is the larger the more central the collision process is. The results show that the thermodynamical equilibrium limit for the entropy production is not reached for such heavy systems as Nb+Nb at 400 MeV/nucleon and that the finite size effects and the dynamical freeze-out process are dominant factors in determining the cluster yield

  8. Variations in pollinator density and impacts on large cardamom (Amomum subulatum Roxb. crop yield in Sikkim Himalaya, India

    Directory of Open Access Journals (Sweden)

    Kailash S. Gaira

    2016-03-01

    Full Text Available Large cardamom (Amomum subulatum Roxb., a perennial cash crop, cultivated under an agroforestry system in the eastern Himalaya of India, is well recognized as a pollination-dependent crop. Observations on pollinator abundance in Mamlay watershed of Sikkim Himalaya were collected during the blooming season to evaluate the pollinator abundance across sites and time frames, and impact of pollinator abundance on crop yield from 2010 to 2012. The results revealed that the bumblebees and honeybees are most frequent visitors of large cardamom flowers. The abundance of honeybees, however, varied between sites for the years 2010–2012, while that of bumblebees varied for the years 2011 and 2012. The abundance of honeybees resulted in a variation within time frames for 2010 and 2011, while that of bumblebees varied for 2010 and 2012 (p<0.01. The density of pollinators correlated positively with the number of flowers of the target crop. The impact of pollinator abundance revealed that the increasing bumblebee visitation resulted in a higher yield of the crop (i.e. 17–41 g/plant and the increasing abundance of all bees (21–41 g/plant was significant (p<0.03. Therefore, the study concluded that the large cardamom yield is sensitive to pollinator abundance and there is a need for adopting the best pollinator conservation and management practices toward sustaining the yield of large cardamom.

  9. Temporal Variations of Water Productivity in Irrigated Corn: An Analysis of Factors Influencing Yield and Water Use across Central Nebraska.

    Directory of Open Access Journals (Sweden)

    Tony Carr

    Full Text Available Water Productivity (WP of a crop defines the relationship between the economic or physical yield of the crop and its water use. With this concept it is possible to identify disproportionate water use or water-limited yield gaps and thereby support improvements in agricultural water management. However, too often important qualitative and quantitative environmental factors are not part of a WP analysis and therefore neglect the aspect of maintaining a sustainable agricultural system. In this study, we examine both the physical and economic WP in perspective with temporally changing environmental conditions. The physical WP analysis was performed by comparing simulated maximum attainable corn yields per unit of water using the crop model Hybrid-Maize with observed data from 2005 through 2013 from 108 farm plots in the Central Platte and the Tri Basin Natural Resource Districts of Nebraska. In order to expand the WP analysis on external factors influencing yields, a second model, Maize-N, was used to estimate optimal nitrogen (N-fertilizer rate for specific fields in the study area. Finally, a vadose zone flow and transport model, HYDRUS-1D for simulating vertical nutrient transport in the soil, was used to estimate locations of nitrogen pulses in the soil profile. The comparison of simulated and observed data revealed that WP was not on an optimal level, mainly due to large amounts of irrigation used in the study area. The further analysis illustrated year-to-year variations of WP during the nine consecutive years, as well as the need to improve fertilizer management to favor WP and environmental quality. In addition, we addressed the negative influence of groundwater depletion on the economic WP through increasing pumping costs. In summary, this study demonstrated that involving temporal variations of WP as well as associated environmental and economic issues can represent a bigger picture of WP that can help to create incentives to sustainably

  10. Effects of energy variations of ions influencing a target on implantation

    International Nuclear Information System (INIS)

    Astakhov, V.P.; Rubtsov, V.A.; Aranovich, R.M.; Pavlov, P.V.

    1981-01-01

    In cases of phosphorus and boron ion implantation into silicon the dependence of electrophysical properties of ion-doped layers and target material near the layer boundaries on energy variation conditions of influencing ions is observed. A physical model explaining the dependence is proposed. It is found that for the target, being at room temperature, after successive annealing the qualitative characteristics of conditions (i.e. energy increase and decrease) on implantation of phosphorus ions into p-silicon and boron ions into n-silicon, as well as the value of energy stages, define rhosub(l) ion-doped layer resistivity and tausub(mc) nonequilibrium minority carrier lifetime in the base of p-n transitions. The essence of the effects observed is that for equal sets of Esub(i) ion energy values and PHIsub(i) corresponding phases at maximum energy used exceeding 30 keV, successive energy increase during implantation, when E 1 2 1 mode), leads to smaller rhosub(e) values and greater tausub(mc) than in case of successive energy decrease, when E 1 >E 2 >...E(E 2 mode) for any fixed annealing temperature. In cases when the maximum energy does not exceed 30 KeV, the E 1 and E 2 modes lead to analogous rhosub(e) and tausub(mc) values. The E 2 mode leads to enrichment of the ion-implanted layer with associations and complexes on the basis of interstitial atoms in comparison with the E 1 mode. The associations and complexes on thermal treatment are reformed into the higher-temperature interstitial complexes increasing rhosub(e) and decreasing tausub(mc). Supposition about the effect of these complexes and processes of structural transformations on annealing, hampering-improvement of structural properties of the ion-implanted layer and a crystal region bordered on it [ru

  11. UAV based mapping of variation in grassland yield for forage production in Arctic environments

    Science.gov (United States)

    Davids, C.; Karlsen, S. R.; Jørgensen, M.; Ancin Murguzur, F. J.

    2017-12-01

    Grassland cultivation for animal feed is the key agricultural activity in northern Norway. Even though the growing season has increased by at least a week in the last 30 years, grassland yields appear to have declined, probably due to more challenging winter conditions and changing agronomy practices. The ability for local and regional crop productivity forecasting would assist farmers with management decisions and would provide local and national authorities with a better overview over productivity and potential problems due to e.g. winter damage. Remote sensing technology has long been used to estimate and map the variability of various biophysical parameters, but calibration is important. In order to establish the relationship between spectral reflectance and grass yield in northern European environments we combine Sentinel-2 time series, UAV-based multispectral measurements, and ground-based spectroradiometry, with biomass analyses and observations of species composition. In this presentation we will focus on the results from the UAV data acquisition. We used a multirotor UAV with different sensors (a multispectral Rikola camera, and NDVI and RGB cameras) to image a number of cultivated grasslands of different age and productivity in northern Norway in June/July 2016 and 2017. Following UAV data acquisition, 10 to 20 in situ measurements were made per field using a FieldSpec3 (350-2500 nm). In addition, samples were taken to determine biomass and grass species composition. The imaging and sampling was done immediately prior to harvesting. The Rikola camera, when used as a stand-alone camera mounted on a UAV, can collect 15 bands with a spectral width of 10-15 nm in the range between 500-890 nm. In the initial analysis of the 2016 data we investigated how well different vegetation indices correlated with biomass and showed that vegetation indices that include red edge bands perform better than widely used indices such as NDVI. We will extend the analysis with

  12. Ion-Smashing yields new knowledge, but some still question risk

    CERN Multimedia

    Weaver, Carolyn

    2006-01-01

    "Experimental results at Brookhaven National Laboratory's supercollider that replicate in miniature the "Big Bang", whn the universe expode into being, were names the top physics story of 2005 by the American Institute of Physis. But some observers say that the possible risks of the experiments, which smash together gold ions traveling near the speed of light, remain an open question"

  13. Variations of Growth and Toxin Yield in Cylindrospermopsis raciborskii under Different Phosphorus Concentrations

    Directory of Open Access Journals (Sweden)

    Yiming Yang

    2016-12-01

    Full Text Available The bloom-forming cyanobacteria, Cylindrospermopsis raciborskii, is a producer of the cytotoxic cylindrospermopsin (CYN. In this study, the growth, toxin yield, and expression of CYN biosynthesis genes of C. raciborskii were examined under varying phosphorus (P concentrations. The results show the cell number at 0.00 and 0.01 mg·L−1 P was significantly lower than that at higher P concentrations (≥0.5 mg·L−1. The chlorophyll a content, filament length, heterocyst, and akinete numbers at P ≤ 0.05 mg·L−1 were also significantly reduced. The intracellular and extracellular CYN concentrations and the extracellular proportions increased during the culture period, and larger values were observed at higher P concentrations. Total CYN content reached 45.34–63.83 fg·cell−1 and extracellular CYN proportion reached 11.49%–20.44% at the stationary growth phase. A significantly positive correlation was observed between CYN production and cell growth rate. Three cyr genes were expressed constantly even at P-deficient conditions. The transcription of cyr genes at P-replete conditions or after P supplementation increased from 1.18-fold to 8.33-fold. In conclusion, C. raciborskii may rapidly reorganize metabolic processes as an adaptive response to environmental P fluctuations. CYN production and cyr gene expression were constitutive metabolic processes in toxic C. raciborskii.

  14. Matching the laser wavelength to the absorption properties of matrices increases the ion yield in UV-MALDI mass spectrometry.

    Science.gov (United States)

    Wiegelmann, Marcel; Soltwisch, Jens; Jaskolla, Thorsten W; Dreisewerd, Klaus

    2013-09-01

    A high analytical sensitivity in ultraviolet matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) is only achieved if the laser wavelength corresponds to a high optical absorption of the matrix. Laser fluence and the physicochemical properties of the compounds, e.g., the proton affinity, also influence analytical sensitivity significantly. In combination, these parameters determine the amount of material ejected per laser pulse and the ion yield, i.e., the fraction of ionized biomolecules. Here, we recorded peptide ion signal intensities as a function of these parameters. Three cinnamic acid matrices were investigated: α-cyano-4-hydroxycinnamic acid, α-cyano-4-chlorocinnamic acid, and α-cyano-2,4-difluorocinnamic acid. In addition, 2,5-dihydroxybenzoic acid was used in comparison experiments. Ion signal intensities "per laser shot" and integrated ion signal intensities were acquired over 900 consecutive laser pulses applied on distinct positions on the dried-droplet sample preparations. With respect to laser wavelength, the two standard MALDI wavelengths of 337/355 nm were investigated. Also, 305 or 320 nm was selected to account for the blue-shifted absorption profiles of the halogenated derivatives. Maximal peptide ion intensities were obtained if the laser wavelength fell within the peak of the absorption profile of the compound and for fluences two to three times the corresponding ion detection threshold. The results indicate ways for improving the analytical sensitivity in MALDI-MS, and in particular for MALDI-MS imaging applications where a limited amount of material is available per irradiated pixel.

  15. Variation in composition and yield of foliage oil of eucalyptus polybractea

    International Nuclear Information System (INIS)

    Iqbal, Z.; Akhtar, M.; Qureshi, T.M.; Ahhter, J.; Ahmad, R.

    2011-01-01

    Eucalyptus polybractea (blue mallee) is the essential oil rich species used in the commercial production of pharmaceutical-grade Eucalyptus oil in Australia. This species was grown at Nuclear Institute for Agriculture and Biology (NIAB), Faisalabad, Pakistan during 2004-08 to investigate the quantity and quality of its foliage oil. The oils were extracted by hydro-distillation method, from the leaves of four year aged ten E. polybractea plants. The data showed a significant intra-species variation in their oil contents (29.3 to 41.8 mg g-1 fresh weight of leaves). Out of ten plants eight contained oil >30 mg g/sup -1/ fresh weight of leaves. The components of the extracted oils varied from 12-26 as detected by GC/FID on Carbowax 20 M packed glass column. Among all the oil components, 1, 8-cineole was the major compound (91.7-94.2 %), while the other identified compounds were alpha-pinene (0-1.2 %), beta-pinene (0.4-2.3 %), limonene (0.2-1.3 %), p-cymene (1.23-2.75 %), and terpinene-4-ol (0.6-0.92 %). The extracted oils from all the Eucalyptus polybractea plants contained high amount of 1, 8-cineole (>90 %), therefore, classified as species of high quality medicinal oil. (author)

  16. Partial ion yield and NEXAFS of 2-(perfluorooctyl)ethanethiol self-assembled monolayer: Comparison with PTFE results

    CERN Document Server

    Setoyama, H; Murase, T; Imamura, M; Mase, K; Okudaira, K K; Hara, M; Ueno, N

    2003-01-01

    Partial-ion-yield (PIY) spectra using ion time-of-flight (TOF) method and near-edge absorption fine structure (NEXAFS) spectra were measured for 2-(perfluorooctyl)ethanethiol [CF sub 3 (CF sub 2) sub 7 (CH sub 2) sub 2 SH] self-assembled monolayer (F8-SAM) on Au(1 1 1) near carbon K-edge. The PIY spectra of the F8-SAM at the magic angle, where -CF sub 3 groups exist at the surface were compared with those of the rubbed polytetrafluoroethylene (PTFE) thin film. The F sup + intensity from the F8-SAM at the photon energy of the sharp peak of the NEXAFS, which originates from the excitation of C1s electron to sigma sup * (C-F) states at -CF sub 2 - chain, was extremely smaller than that from the rubbed PTFE film. This result clearly indicates that the ions observed by PIY do not originate from the film inside but from the surface. This was confirmed by changes in ion-TOF mass spectra during soft X-ray induced etching of the F8-SAM. The NEXAFS peaks of the F8-SAM were also assigned by considering PIY results.

  17. Fission fragment yields from heavy-ion-induced reactions measured with a fragment separator

    Science.gov (United States)

    Tarasov, O. B.; Delaune, O.; Farget, F.; Morrissey, D. J.; Amthor, A. M.; Bastin, B.; Bazin, D.; Blank, B.; Cacéres, L.; Chbihi, A.; Fernández-Dominguez, B.; Grévy, S.; Kamalou, O.; Lukyanov, S. M.; Mittig, W.; Pereira, J.; Perrot, L.; Saint-Laurent, M.-G.; Savajols, H.; Sherrill, B. M.; Stodel, C.; Thomas, J. C.; Villari, A. C.

    2018-04-01

    The systematic study of fission fragment yields under different initial conditions has provided valuable experimental data for benchmarking models of fission product yields. Nuclear reactions using inverse kinematics coupled to the use of a high-resolution spectrometer with good fragment identification are shown here to be a powerful tool to measure the inclusive isotopic yields of fission fragments. In-flight fusion-fission was used in this work to produce secondary beams of neutron-rich isotopes in the collisions of a 238U beam at 24 MeV/u with 9Be and 12C targets at GANIL using the LISE3 fragment separator. Unique identification of the A, Z, and atomic charge state, q, of fission products was attained with the Δ E- TKE-B ρ- ToF measurement technique. Mass, and atomic number distributions are reported for the two reactions. The results show the importance of different reaction mechanisms in the two cases. The optimal target material for higher yields of neutron-rich high- Z isotopes produced in fusion-fission reactions as a function of projectile energy is discussed.

  18. High-energy neutron yields in interactions of carbon ions with 114Sn and 124Sn nuclei

    International Nuclear Information System (INIS)

    Blinov, M.B.; Gavrilov, B.P.; Kovalenko, S.S.; Kozulin, Eh.M.; Mozhaev, A.N.; Oganesyan, Yu.Ts.; Penionzhkevich, Yu.Eh.

    1984-01-01

    The measurements of the yields of neutrons (energy more than 5 MeV) emitted in the interactions of carbon-12 ions (9 MeV/nucl.) with nuclei of two tin isotopes are conducted. The results obtained prove the effect of nucleon composition of a nucleus on the process of formation of high-energy neutrons. To clarify the concrete interaction mechanism it is necessary to perform systematic research for a number of isotopes differing in the relation of the number of neutrons and protons and binding energies of the last neutron

  19. Threshold photoelectron spectroscopy and photoionization total ion yield spectroscopy of simple organic acids, aldehydes, ketones and amines

    International Nuclear Information System (INIS)

    Yencha, Andrew J; Malins, Andrew E R; Siggel-King, Michele R F; Eypper, Marie; King, George C

    2009-01-01

    We have initiated a research program to investigate the ionization behavior of some simple organic molecules containing the carboxyl group (R 2 C=O), where R could be H, OH, NH 2 , or CH 3 or other aliphatic or aromatic carbon groups, using threshold photoelectron spectroscopy and photoionization total ion yield spectroscopy. We report here on the simplest organic acid, formic acid, and two simple aldehydes: acetaldehyde and the simplest unsaturated aldehyde, 2-propenal (acrolein). The objective of this study was to characterize the valence cationic states of these molecules with vibrational structural resolution.

  20. Morphology variation, composition alteration and microstructure changes in ion-irradiated 1060 aluminum alloy

    Science.gov (United States)

    Wan, Hao; Si, Naichao; Wang, Quan; Zhao, Zhenjiang

    2018-02-01

    Morphology variation, composition alteration and microstructure changes in 1060 aluminum irradiated with 50 keV helium ions were characterized by field emission scanning electron microscopy (FESEM) equipped with x-ray elemental scanning, 3D measuring laser microscope and transmission electron microscope (TEM). The results show that, helium ions irradiation induced surface damage and Si-rich aggregates in the surfaces of irradiated samples. Increasing the dose of irradiation, more damages and Si-rich aggregates would be produced. Besides, defects such as dislocations, dislocation loops and dislocation walls were the primary defects in the ion implanted layer. The forming of surface damages were related with preferentially sputtering of Al component. While irradiation-enhanced diffusion and irradiation-induced segregation resulted in the aggregation of impurity atoms. And the aggregation ability of impurity atoms were discussed based on the atomic radius, displacement energy, lattice binding energy and surface binding energy.

  1. Study of rare-gas dimer ions by the variational cellular method

    International Nuclear Information System (INIS)

    Wentzcovitch, R.M.M.

    1982-01-01

    The Variational Cellular Method to study ionized molecules in their ground and excited states with the scope of testing the validity of such method in these cases have been used. The ions studied are Ne +2 , Ar +2 , where the latter is the system with the largest number of electrons tested by VCM so far. The electronic transitions in these systems are important mechanisms of efficiency decay for the noble gas halide lasers ('excimer lasers'). (Author) [pt

  2. Electron yield from Be-Cu induced by highly charged Xe q+ ions

    Czech Academy of Sciences Publication Activity Database

    Krása, Josef; Láska, Leoš; Stöckli, M. P.; Fehrenbach, C. W.

    2002-01-01

    Roč. 196, - (2002), s. 61-67 ISSN 0168-583X R&D Projects: GA AV ČR IAA1010105; GA MŠk LN00A100 Institutional research plan: CEZ:AV0Z1010921 Keywords : highly charged ion-induced electron emission * angle impact effect * Be-Cu Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.158, year: 2002

  3. New ion exchange resin designs and regeneration procedures yield improved performance for various condensate polishing applications

    International Nuclear Information System (INIS)

    Najmy, S.W.

    2002-01-01

    Condensate polishing is an application with many different design and operational aspects. The past decade has brought new challenges for improved water quality with respect to both soluble and insoluble contaminants. Nonetheless, the endeavors to understand the compositional complexities of the ion exchange resin bead and the convoluted dynamics of ion exchange chemistry and chemical engineering mechanisms occurring within the mixed bed condensate polisher have brought new ideas and expectations for ion exchange resin in deep-bed condensate polishers than ever before. The new products and procedures presented here are a collaboration of a great deal of effort on the part of researchers, consultants, system engineers, station chemists, lab technicians and others. The studies discussed in this paper unequivocally demonstrate the merits of: 1. A specially designed cation resin to achieve greater than 95% insoluble iron removal efficiency, 2. A less-separable mixed resin for improved control of reactor water sulfate in BWR primary cycles, 3. Applying increased levels of regeneration chemicals and retrofitting the service vessels with re-mixing capability to improve the operation of deep-bed condensate polishers in PWR secondary cycles. (authors)

  4. Flexible probe for measuring local conductivity variations in Li-ion electrode films

    Science.gov (United States)

    Hardy, Emilee; Clement, Derek; Vogel, John; Wheeler, Dean; Mazzeo, Brian

    2018-04-01

    Li-ion battery performance is governed by electronic and ionic properties of the battery. A key metric that characterizes Li-ion battery cell performance is the electronic conductivity of the electrodes, which are metal foils with thin coatings of electrochemically active materials. To accurately measure the spatial variation of electronic conductivity of these electrodes, a micro-four-line probe (μ4LP) was designed and used to non-destructively measure the properties of commercial-quality Li-ion battery films. This previous research established that the electronic conductivity of film electrodes is not homogeneous throughout the entirety of the deposited film area. In this work, a micro-N-line probe (μNLP) and a flexible micro-flex-line probe (μFLP) were developed to improve the non-destructive micro-scale conductivity measurements that we can take. These devices were validated by comparing test results to that of the predecessor, the micro-four-line probe (μ4LP), on various commercial-quality Li-ion battery electrodes. Results show that there is significant variation in conductivity on a millimeter and even micrometer length scale through the electrode film. Compared to the μ4LP, the μNLP and μFLP also introduce additional measurement configuration possibilities, while providing a more robust design. Researchers and manufacturers can use these probes to identify heterogeneity in their electrodes during the fabrication process, which will lead to the development of better batteries.

  5. Seasonal variation of Martian pick-up ions: Evidence of breathing exosphere

    Science.gov (United States)

    Yamauchi, M.; Hara, T.; Lundin, R.; Dubinin, E.; Fedorov, A.; Sauvaud, J.-A.; Frahm, R. A.; Ramstad, R.; Futaana, Y.; Holmstrom, M.; Barabash, S.

    2015-12-01

    The Mars Express (MEX) Ion Mass Analyser (IMA) found that the detection rate of the ring-like distribution of protons in the solar wind outside of the bow shock to be quite different between Mars orbital summer (around perihelion) and orbital winter (around aphelion) for four Martian years, while the north-south asymmetry is much smaller than the perihelion-aphelion difference. Further analyses using eight years of MEX/IMA solar wind data between 2005 and 2012 has revealed that the detection frequency of the pick-up ions originating from newly ionized exospheric hydrogen with certain flux strongly correlates with the Sun-Mars distance, which changes approximately every two years. Variation due to the solar cycle phase is not distinguishable partly because this effect is masked by the seasonal variation under the MEX capability of plasma measurements. This finding indicates that the variation in solar UV has a major effect on the formation of the pick-up ions, but this is not the only controlling factor.

  6. A very high yield electron impact ion source for analytical mass spectrometry

    International Nuclear Information System (INIS)

    Koontz, S.L.; Bonner Denton, M.

    1981-01-01

    A novel ion source designed for use in mass spectrometric determination of organic compounds is described. The source is designed around a low pressure, large volume, hot cathode Penning discharge. The source operates in the 10 -4 - 10 -7 torr pressure domain and is capable of producing focusable current densities several orders of magnitude greater than those produced by conventional Nier -type sources. Mass spectra of n-butane and octafluoro-2-butene are presented. An improved signal-to-noise ratio is demonstrated with a General Electric Monopole 300 mass spectrometer. (orig.)

  7. Arguments for fundamental emission by the parametric process L yields T + S in interplanetary type III bursts. [langmuir, electromagnetic, ion acoustic waves (L, T, S)

    Science.gov (United States)

    Cairns, I. H.

    1984-01-01

    Observations of low frequency ion acoustic-like waves associated with Langmuir waves present during interplanetary Type 3 bursts are used to study plasma emission mechanisms and wave processes involving ion acoustic waves. It is shown that the observed wave frequency characteristics are consistent with the processes L yields T + S (where L = Langmuir waves, T = electromagnetic waves, S = ion acoustic waves) and L yields L' + S proceeding. The usual incoherent (random phase) version of the process L yields T + S cannot explain the observed wave production time scale. The clumpy nature of the observed Langmuir waves is vital to the theory of IP Type 3 bursts. The incoherent process L yields T + S may encounter difficulties explaining the observed Type 3 brightness temperatures when Langmuir wave clumps are incorporated into the theory. The parametric process L yields T + S may be the important emission process for the fundamental radiation of interplanetary Type 3 bursts.

  8. Mutation breeding and submerged fermentation of a Pleurotus polysaccharide high-yield strain with low-energy heavy ions implantation

    International Nuclear Information System (INIS)

    Chen Henglei; Wan Honggui; Lv Changwu; Zeng Xianxian

    2010-01-01

    Pleurotus polysaccharide high-yield strains were selected through a method of auxotrophic primary screening and Shake-flask fermentation re-screening after low-energy heavy ions (the fluence of 1.2 x 10 16 N + /cm 2 at the energy of 15 keV) stepwise implantation. Two Pleurotus polysaccharide high-yield strains, PFPH-1 and PFPH-2, were selected with stable mycelium polysaccharide yield. The mycelium polysaccharide yield of PFPH-1 and PFPH-2 increased by 46.55% and 75.14%, respectively, compared to the original strain. The accumulation of mycelium biomass and intracellular polysaccharides were monitored in the submerged fermentation of Pleurotus ferulae by supplementation of various carbon and nitrogen sources as well as inorganic salts and pH alteration. The optima1 submerged fermentation medium favoring the accumulation of mycelium biomass and intracellular polysaccharides of PFPH-2 consisted of 1.0% wheat flour, 2.0% sucrose, 2.0% soybean flour, 1.5% bran extract, 0.2% K 2 HPO 4 , and 0.15% MgSO 4 ·7H 2 O, with a fittest pH value of 5.64. The orthogonal combination of the optimal carbon and nitrogen sources with inorganic salts indicates a synergistic effect on the accumulation of mycelium biomass and intracellular polysaccharides in the submerged fermentation of PFPH-2. The yield of mycelium polysaccharides of PFPH-2 increased to 903.73 ± 1.23 mg·L -1 by the end of fermentation. (authors)

  9. K-shell Fluorescence Yields of Li- to F-like Ions

    Science.gov (United States)

    Manson, S. T.; Hasoglu, M. F.; Gorczyca, T. W.; Badnell, N. R.; Savin, D. W.

    2007-06-01

    We have investigated the accuracy of the commonly-used fluorescence/Auger database. These data were determined from configuration average, LS, singly-charged atomic physics calculations and were then scaled up through Z=30 for all isoelectronic sequences through the iron peak elements. We have carried out new calculations, using the AUTOSTRUCTURE package, and demonstrate the significance of including properly such physical effects as correct configuration averaging (CA), semi-relativistic (i.e., spin-orbit) effects, and the previously-overlooked need to tailor the CA itself to the specific physical process of interest, showing that the extant database includes significant inaccuracies. Finally, we have completed an investigation of the isoelectronic sequences of all second-row ions. This work was supported in part by NASA APRA and SHP SR&T programs.

  10. Analysis of factors which limited the spatial variation of barley yield on the forest-steppe chernozems of Kursk region

    Science.gov (United States)

    Belik, Anton; Vasenev, Ivan; Jablonskikh, Lidia; Bozhko, Svetlana

    2017-04-01

    The crop yield is the most important indicator of the efficiency of agricultural production. It is the function that depends on a large number of groups of independent variables, such as the weather, soil fertility and overall culture agriculture. A huge number of combinations of these factors contribute to the formation of high spatial variety of crop yields within small areas, includes the slope agrolandscapes in Kursk region. Spatial variety of yield leads to a significant reduction in the efficiency of agriculture. In this connection, evaluation and analysis of the factors, which limits the yield of field crops is a very urgent proble in agroecology. The research was conducted in the period of 2003-2004 on a representative field. The typical and leached chernozems with the varying thickness and of erosion degree are dominated in soil cover. At the time of field research studied areas were busy by barley. The reseached soils have an average and increased fertility level. Chernozem typical full-face, and the leached contain an average of 4.5-6% humus, close to neutral pH, favorable values of physico-chemical parameters, medium and high content of nutrients. The eroded chernozems differs agrogenic marked declining in fertility parameters. The diversity of meso- and micro-relief in the fields and soil cover influence to significant spatial variety of fertility. For example the content of nutrients in the soil variation can be up to 5-fold level. High spatial heterogeneity of soils fertility ifluence to barley yield variety. During research on the productivity of the field varied in the range of 20-43 c/ha, and 7-44 c/ha (2004). Analysis of the factors, which limited the yield of barley, showed that the first priorities occupy unregulated characterises: slope angle and the classification of soils (subtype and race of chernozem and the difference in the degree of erosion), which determines the development of erosion processes and redistribution available to plants

  11. Variations and Transmission of QTL Alleles for Yield and Fiber Qualities in Upland Cotton Cultivars Developed in China

    Science.gov (United States)

    Zhang, Tianzhen; Qian, Neng; Zhu, Xiefei; Chen, Hong; Wang, Sen; Mei, Hongxian; Zhang, Yuanming

    2013-01-01

    Cotton is the world’s leading cash crop, and genetic improvement of fiber yield and quality is the primary objective of cotton breeding program. In this study, we used various approaches to identify QTLs related to fiber yield and quality. Firstly, we constructed a four-way cross (4WC) mapping population with four base core cultivars, Stoneville 2B, Foster 6, Deltapine 15 and Zhongmiansuo No.7 (CRI 7), as parents in Chinese cotton breeding history and identified 83 QTLs for 11 agronomic and fiber quality traits. Secondly, association mapping of agronomical and fiber quality traits was based on 121 simple sequence repeat (SSR) markers using a general linear model (GLM). For this, 81 Gossypium hirsutum L. accessions including the four core parents and their derived cultivars were grown in seven diverse environments. Using these approaches, we successfully identified 180 QTLs significantly associated with agronomic and fiber quality traits. Among them were 66 QTLs that were identified via linkage disequilibrium (LD) and 4WC family-based linkage (FBL) mapping and by previously published family-based linkage (FBL) mapping in modern Chinese cotton cultivars. Twenty eight and 44 consistent QTLs were identified by 4WC and LD mapping, and by FBL and LD mapping methods, respectively. Furthermore, transmission and variation of QTL-alleles mapped by LD association in the three breeding periods revealed that some could be detected in almost all Chinese cotton cultivars, suggesting their stable transmission and some identified only in the four base cultivars and not in the modern cultivars, suggesting they were missed in conventional breeding. These results will be useful to conduct genomics-assisted breeding effectively using these existing and novel QTL alleles to improve yield and fiber qualities in cotton. PMID:23468939

  12. Measurements of neutron yields and radioactive isotope transmutation in collisions of relativistic ions with heavy nuclei

    International Nuclear Information System (INIS)

    Brandt, R.

    1999-01-01

    The paper is based on the report presented at the 85th Session of the JINR Scientific Council. Some aspects of experimental studies of the problem of reprocessing radioactive wastes by means of transmutation in the fields of neutrons generated by relativistic particle beams are discussed. Research results on measurement of neutron yields in heavy targets irradiated with protons at energies up to 3.7 GeV as well as transmutation cross sections of some fission products (I-129) and actinides (Np-237) using radiochemical methods, activation detectors, solid state nuclear track detectors and other methods are presented. Experiments have been performed at the accelerator complex of the Laboratory of High Energies, JINR. Analogous results obtained by other research groups are also discussed

  13. Correlations between reaction product yields as a tool for probing heavy-ion reaction scenarios

    International Nuclear Information System (INIS)

    Gawlikowicz, W.; Agnihotri, D. K.; Baldwin, S. A.; Schroeder, W. U.; Toke, J.; Charity, R. J.; Sarantites, D. G.; Sobotka, L. G.; Souza, R. T. de; Barczyk, T.; Grotowski, K.; Micek, S.; Planeta, R.; Sosin, Z.

    2010-01-01

    Experimental multidimensional joint distributions of neutrons and charged reaction products were analyzed for 136 Xe + 209 Bi reactions at E/A=28, 40, and 62 MeV and were found to exhibit several different types of prominent correlation patterns. Some of these correlations have a simple explanation in terms of the system excitation energy and pose little challenge to most statistical decay theories. However, several other types of correlation patterns are difficult to reconcile with some, but not other, possible reaction scenarios. In this respect, correlations between the average atomic numbers of intermediate-mass fragments, on the one hand, and light particle multiplicities, on the other, are notable. This kind of multiparticle correlation provides a useful tool for probing reaction scenarios, which is different from the traditional approach of interpreting inclusive yields of individual reaction products.

  14. Source of Global Scale Variations in the Midday Vertical Content of Ionospheric Metal Ions

    Science.gov (United States)

    Joiner, J.; Grebowsky, J. M.; Pesnell, W. D.; Aikin, A. C.; Goldberg, Richard A.

    1999-01-01

    An analysis of long baseline NIMBUS 7 SBUV (Solar Backscatter UV Spectrometer) observations of the latitudinal variation of the noontime vertical Mg' content above approx. 70 km have revealed seasonal, solar activity and magnetic activity dependencies in the Mg+ content. The distributions were categorized in terms of magnetic coordinates partially because transport processes lifting metallic ions from the main meteor ionization layer below 100 km up into the F- region and down again are controlled by electrodynamical processes. Alternatively, the Nimbus Mg+ distributions may simply be a result of ion/neutral chemistry changes resulting from atmospheric changes and not dynamics. In such a case magnetic control would not dominate the distributions. Using in situ satellite measurements of metal ions from the Atmosphere Explorer satellites in the region above the main meteor layer and published sounding rocket measurements of the main metallic ion layers, the effects of the dynamics on the vertical content are delineated. The consequences of atmospheric changes on the vertical content are explored by separating the Nimbus measurements in a geodetic frame of reference.

  15. Water chemistry in Kuji river. Its spatial and seasonal variations in major ions and organic substances

    Energy Technology Data Exchange (ETDEWEB)

    Niina, Toshiaki; Matsunaga, Takeshi; Amano, Hikaru [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-02-01

    As a basic research with a aim to clarify the migration behavior of radionuclides in rivers, the characteristics of dissolved ions and organic substances in river water, which characteristics may affect the behavior, was investigated. The investigation was carried out for the Kuji river in the northern Kanto district (Japan) comprising four sampling campaigns in 1994 for 10 locations from the upstream to the downstream. Concentrations of major ions, iron and manganese species and organic substances were analyzed in laboratory. Values of temperature of the water, pH, conductivity, dissolved oxygen were measured in the field. This investigation was conducted mainly under low water flow conditions of the river, while a limited number of campaigns were under high flow conditions due to precipitation events. The concentrations of major inorganic ions increased steadily toward the down-stream, resulting in approximately two times increase for the traveling distance of 100 km. They showed a seasonal variation that they were highest in the spring and lowest in the autumn when there were most concentrated precipitation events in a year. The constituents were mainly Na{sup +}, Ca{sup 2+}, SO{sub 4}{sup 2-} and HCO{sub 3}{sup -}, and were similar for every sampling locations and seasons. Concentrations of dissolved organic substances (carbon compounds) were lowest in the upstream and increased about twice in the downstream as well as major inorganic ions. Their level was 1-3 mg/l, which can be ranked as relatively lower in general values for fresh water environments. They were highest in the spring (average over the locations: 2.2 mg/l) and lowest in the autumn (1.3 mg/l) and also in the winter (1.3 mg/l). These results will be useful as a basic understanding of spatial and seasonal variations of river water chemistry, especially related to the organic substances which can bind with radionuclides to make a mobile complex. (author).

  16. Water chemistry in Kuji river. Its spatial and seasonal variations in major ions and organic substances

    International Nuclear Information System (INIS)

    Niina, Toshiaki; Matsunaga, Takeshi; Amano, Hikaru

    1996-02-01

    As a basic research with a aim to clarify the migration behavior of radionuclides in rivers, the characteristics of dissolved ions and organic substances in river water, which characteristics may affect the behavior, was investigated. The investigation was carried out for the Kuji river in the northern Kanto district (Japan) comprising four sampling campaigns in 1994 for 10 locations from the upstream to the downstream. Concentrations of major ions, iron and manganese species and organic substances were analyzed in laboratory. Values of temperature of the water, pH, conductivity, dissolved oxygen were measured in the field. This investigation was conducted mainly under low water flow conditions of the river, while a limited number of campaigns were under high flow conditions due to precipitation events. The concentrations of major inorganic ions increased steadily toward the down-stream, resulting in approximately two times increase for the traveling distance of 100 km. They showed a seasonal variation that they were highest in the spring and lowest in the autumn when there were most concentrated precipitation events in a year. The constituents were mainly Na + , Ca 2+ , SO 4 2- and HCO 3 - , and were similar for every sampling locations and seasons. Concentrations of dissolved organic substances (carbon compounds) were lowest in the upstream and increased about twice in the downstream as well as major inorganic ions. Their level was 1-3 mg/l, which can be ranked as relatively lower in general values for fresh water environments. They were highest in the spring (average over the locations: 2.2 mg/l) and lowest in the autumn (1.3 mg/l) and also in the winter (1.3 mg/l). These results will be useful as a basic understanding of spatial and seasonal variations of river water chemistry, especially related to the organic substances which can bind with radionuclides to make a mobile complex. (author)

  17. Histograms showing variations in oil yield, water yield, and specific gravity of oil from Fischer assay analyses of oil-shale drill cores and cuttings from the Piceance Basin, northwestern Colorado

    Science.gov (United States)

    Dietrich, John D.; Brownfield, Michael E.; Johnson, Ronald C.; Mercier, Tracey J.

    2014-01-01

    Recent studies indicate that the Piceance Basin in northwestern Colorado contains over 1.5 trillion barrels of oil in place, making the basin the largest known oil-shale deposit in the world. Previously published histograms display oil-yield variations with depth and widely correlate rich and lean oil-shale beds and zones throughout the basin. Histograms in this report display oil-yield data plotted alongside either water-yield or oil specific-gravity data. Fischer assay analyses of core and cutting samples collected from exploration drill holes penetrating the Eocene Green River Formation in the Piceance Basin can aid in determining the origins of those deposits, as well as estimating the amount of organic matter, halite, nahcolite, and water-bearing minerals. This report focuses only on the oil yield plotted against water yield and oil specific gravity.

  18. A Study of Mutation Breeding of High-Yielding Tryptophanase Escherichia coli by Low-Energy N+ Ion Beam Implantation

    International Nuclear Information System (INIS)

    Pang Min; Yao Jianming; Wang Dongmei

    2009-01-01

    Low energy ion beam has been widely applied in microbe breeding, plant breeding, gene transfer and cell modification. In this study, the Escherichia coli (E.coli) strain producing tryptophanase was irradiated by a low energy nitrogen ion beam with an energy of 10 keV at a fluence of 13 x 10 14 N + /cm 2 when glycerin at a 15% concentration was used as a protector. The effect on the biomass of E. coli after N + implantation was analyzed in detail by statistic methods. The screening methods used in this study were proven to be effective. After continuous mutagenicity, a high-yield tryptophanase strain was selected and both its biomass and enzymatic activity were higher than those of the parent strain. The results of scale-up production showed that the biomass could reach wet weight 8.2 g/L and 110 g L-tryptophan could be formed in the volume of the 1l enzymatic reaction system.

  19. Anomalously high yield of doubly charged Si ions sputtered from cleaned Si surface by keV neutral Ar impact

    Energy Technology Data Exchange (ETDEWEB)

    Shinde, N.; Morita, K. E-mail: k-morita@mail.nucl.nagoya-u.ac.jp; Dhole, S.D.; Ishikawa, D

    2001-08-01

    The energy spectra of positively charged and neutral species ejected from the Si(1 1 1) surfaces by keV Ar impact have been measured by means of a combined technique of the time-of-flight (TOF) analysis with the multi-photon resonance ionization spectroscopy (MPRIS). It is shown that positively charged species of Si{sup +}, Si{sup 2+} and SiO{sup +} are ejected from the as-cleaned 7x7 surface by 11 keV Ar impact. It is also shown that Ar sputter cleaning of the as-cleaned 7x7 surface for 14 min at the flux of 2x10{sup 13}/cm{sup 2}s removes completely the oxygen impurity and the yields of Si{sup 2+} is comparable to that of Si{sup +}. Moreover, the ionization probability of Si atoms sputtered is shown to be expressed as an exponential function of the inverse of their velocity. The production mechanism for the doubly charged Si ion is discussed based on the L-shell ionization of Si atoms due to quasi-molecule formation in the collisions of the surface atoms with energetic recoils and subsequent Auger decay of the L-shell vacancy to doubly ionized Si ions.

  20. Runoff and Sediment Yield Variations in Response to Precipitation Changes: A Case Study of Xichuan Watershed in the Loess Plateau, China

    Directory of Open Access Journals (Sweden)

    Tianhong Li

    2015-10-01

    Full Text Available The impacts of climate change on hydrological cycles and water resource distribution is particularly concerned with environmentally vulnerable areas, such as the Loess Plateau, where precipitation scarcity leads to or intensifies serious water related problems including water resource shortages, land degradation, and serious soil erosion. Based on a geographical information system (GIS, and using gauged hydrological data from 2001 to 2010, digital land-use and soil maps from 2005, a Soil and Water Assessment Tool (SWAT model was applied to the Xichuan Watershed, a typical hilly-gullied area in the Loess Plateau, China. The relative error, coefficient of determination, and Nash-Sutcliffe coefficient were used to analyze the accuracy of runoffs and sediment yields simulated by the model. Runoff and sediment yield variations were analyzed under different precipitation scenarios. The increases in runoff and sediment with increased precipitation were greater than their decreases with reduced precipitation, and runoff was more sensitive to the variations of precipitation than was sediment yield. The coefficients of variation (CVs of the runoff and sediment yield increased with increasing precipitation, and the CV of the sediment yield was more sensitive to small rainfall. The annual runoff and sediment yield fluctuated greatly, and their variation ranges and CVs were large when precipitation increased by 20%. The results provide local decision makers with scientific references for water resource utilization and soil and water conservation.

  1. Thermal spike model interpretation of sputtering yield data for Bi thin films irradiated by MeV {sup 84}Kr{sup 15+} ions

    Energy Technology Data Exchange (ETDEWEB)

    Mammeri, S. [Centre de Recherche Nucléaire d’Alger, B.P. 399, 02 Bd. Frantz Fanon, Alger-gare, Algiers (Algeria); Ouichaoui, S., E-mail: souichaoui@gmail.com [Université des Sciences et de la Technologie H. Boumediene (USTHB), Faculté de Physique, Laboratoire SNIRM, B.P. 32, El-Alia, 16111 Bab Ezzouar, Algiers (Algeria); Ammi, H. [Centre de Recherche Nucléaire d’Alger, B.P. 399, 02 Bd. Frantz Fanon, Alger-gare, Algiers (Algeria); Pineda-Vargas, C.A. [iThemba LABS, National Research Foundation, P.O. Box 722, Somerset West 7129 (South Africa); Faculty of Health and Wellness Sciences, CPUT, P.O. Box 1906, Bellville 7535 (South Africa); Dib, A. [Centre de Recherche Nucléaire d’Alger, B.P. 399, 02 Bd. Frantz Fanon, Alger-gare, Algiers (Algeria); Msimanga, M. [iThemba LABS, National Research Foundation, P. Bag 11, Wits 2050, Johannesburg (South Africa); Department of Physics, Tshwane University of Technology, P. Bag X680, Pretoria 001 (South Africa)

    2015-07-01

    A modified thermal spike model initially proposed to account for defect formation in metals within the high heavy ion energy regime is adapted for describing the sputtering of Bi thin films under MeV Kr ions. Surface temperature profiles for both the electronic and atomic subsystems have been carefully evaluated versus the radial distance and time with introducing appropriate values of the Bi target electronic stopping power for multi-charged Kr{sup 15+} heavy ions as well as different target physical proprieties like specific heats and thermal conductivities. Then, the total sputtering yields of the irradiated Bi thin films have been determined from a spatiotemporal integration of the local atomic evaporation rate. Besides, an expected non negligible contribution of elastic nuclear collisions to the Bi target sputtering yields and ion-induced surface effects has also been considered in our calculation. Finally, the latter thermal spike model allowed us to derive numerical sputtering yields in satisfactorily agreement with existing experimental data both over the low and high heavy ion energy regions, respectively, dominated by elastic nuclear collisions and inelastic electronic collisions, in particular with our data taken recently for Bi thin films irradiated by 27.5 MeV Kr{sup 15+} heavy ions. An overall consistency of our model calculation with the predictions of sputtering yield theoretical models within the target nuclear stopping power regime was also pointed out.

  2. Estimation of effects of photosynthesis response functions on rice yields and seasonal variation of CO2 fixation using a photosynthesis-sterility type of crop yield model

    International Nuclear Information System (INIS)

    Kaneko, D.; Moriwaki, Y.

    2008-01-01

    This study presents a crop production model improvement: the previously adopted Michaelis-Menten (MM) type photosynthesis response function (fsub(rad-MM)) was replaced with a Prioul-Chartier (PC) type function (fsub(rad-PC)). The authors' analysis reflects concerns regarding the background effect of global warming, under simultaneous conditions of high air temperature and strong solar radiation. The MM type function fsub(rad-MM) can give excessive values leading to an overestimate of photosynthesis rate (PSN) and grain yield for paddy-rice. The MM model is applicable to many plants whose (PSN) increases concomitant with increased insolation: wheat, maize, soybean, etc. For paddy rice, the PSN apparently shows a maximum PSN. This paper proves that the MM model overestimated the PSN for paddy rice for sufficient solar radiation: the PSN using the PC model yields 10% lower values. However, the unit crop production index (CPIsub(U)) is almost independent of the MM and PC models because of respective standardization of both PSN and crop production index using average PSNsub(0) and CPIsub(0). The authors improved the estimation method using a photosynthesis-and-sterility based crop situation index (CSIsub(E)) to produce a crop yield index (CYIsub(E)), which is used to estimate rice yields in place of the crop situation index (CSI); the CSI gives a percentage of rice yields compared to normal annual production. The model calculates PSN including biomass effects, low-temperature sterility, and high-temperature injury by incorporating insolation, effective air temperature, the normalized difference vegetation index (NDVI), and effects of temperature on photosynthesis. Based on routine observation data, the method enables automated crop-production monitoring in remote regions without special observations. This method can quantify grain production early to raise an alarm in Southeast Asian countries, which must confront climate fluctuation through this era of global

  3. Comparison of the target-thickness dependence of the convoy electron yield and the Rydberg electron yield measured in coincidence with exit charge states in fast ion-solid collisions

    International Nuclear Information System (INIS)

    Gaither, C.C. III; Breinig, M.; Freyou, J.; Underwood, T.A.

    1988-01-01

    We have simultaneously measured the yield of convoy electrons and the yield of electrons in high Rydberg states of the projectile (n /approx gt/ 70), produced by 2MeV/u C projectiles passing through C foils, whose thicknesses range from 4--10 ug/cm 2 , for incident charge states q/sub i/ = 4--6 and exit charge states q/sub e/ = 4--6. We have found that these yields exhibit similar trends as a function of foil thickness, but that, nevertheless, the ratio of the number of convoy electrons detected in coincidence with ions of exit charge state q/sub e/ to the number of electrons detected in high Rydberg states of ions with the same exit charge state is a function of foil thickness. This may be due to a broadening of the convoy electron energy spectrum with increasing foil thickness. 6 refs., 3 figs

  4. Kinetic Alfven wave with density variation and loss-cone distribution function of multi-ions in PSBL region

    Science.gov (United States)

    Tamrakar, Radha; Varma, P.; Tiwari, M. S.

    2018-05-01

    Kinetic Alfven wave (KAW) generation due to variation of loss-cone index J and density of multi-ions (H+, He+ and O+) in the plasma sheet boundary layer region (PSBL) is investigated. Kinetic approach is used to derive dispersion relation of wave using Vlasov equation. Variation of frequency with respect to wide range of k⊥ρi (where k⊥ is wave vector across the magnetic field, ρi is gyroradius of ions and i denotes H+, He+ and O+ ions) is analyzed. It is found that each ion gyroradius and number density shows different effect on wave generation with varying width of loss-cone. KAW is generated with multi-ions (H+, He+ and O+) over wide regime for J=1 and shows dissimilar effect for J=2. Frequency is reduced with increasing density of gyrating He+ and O+ ions. Wave frequency is obtained within the reported range which strongly supports generation of kinetic Alfven waves. A sudden drop of frequency is also observed for H+ and He+ ion which may be due to heavy penetration of these ions through the loss-cone. The parameters of PSBL region are used for numerical calculation. The application of these results are in understanding the effect of gyrating multi-ions in transfer of energy and Poynting flux losses from PSBL region towards ionosphere and also describing the generation of aurora.

  5. Common Ion Effects In Zeoponic Substrates: Dissolution And Cation Exchange Variations Due to Additions of Calcite, Dolomite and Wollastonite

    Science.gov (United States)

    Beiersdorfer, R. E.; Ming, D. W.; Galindo, C., Jr.

    2003-01-01

    c1inoptilolite-rich tuff-hydroxyapatite mixture (zeoponic substrate) has the potential to serve as a synthetic soil-additive for plant growth. Essential plant macro-nutrients such as calcium, phosphorous, magnesium, ammonium and potassium are released into solution via dissolution of the hydroxyapatite and cation exchange on zeolite charged sites. Plant growth experiments resulting in low yield for wheat have been attributed to a Ca deficiency caused by a high degree of cation exchange by the zeolite. Batch-equilibration experiments were performed in order to determine if the Ca deficiency can be remedied by the addition of a second Ca-bearing, soluble, mineral such as calcite, dolomite or wollastonite. Variations in the amount of calcite, dolomite or wollastonite resulted in systematic changes in the concentrations of Ca and P. The addition of calcite, dolomite or wollastonite to the zeoponic substrate resulted in an exponential decrease in the phosphorous concentration in solution. The exponential rate of decay was greatest for calcite (5.60 wt. % -I), intermediate for wollastonite (2.85 wt.% -I) and least for dolomite (1.58 wt.% -I). Additions of the three minerals resulted in linear increases in the calcium concentration in solution. The rate of increase was greatest for calcite (3.64), intermediate for wollastonite (2.41) and least for dolomite (0.61). The observed changes in P and Ca concentration are consistent with the solubilities of calcite, dolomite and wollastonite and with changes expected from a common ion effect with Ca. Keywords: zeolite, zeoponics, common-ion effect, clinoptilolite, hydroxyapatite

  6. Steady State Sputtering Yields and Surface Compositions of Depleted Uranium and Uranium Carbide bombarded by 30 keV Gallium or 16 keV Cesium Ions.

    Energy Technology Data Exchange (ETDEWEB)

    Siekhaus, W. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Teslich, N. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Weber, P. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-10-23

    Depleted uranium that included carbide inclusions was sputtered with 30-keV gallium ions or 16-kev cesium ions to depths much greater than the ions’ range, i.e. using steady-state sputtering. The recession of both the uranium’s and uranium carbide’s surfaces and the ion corresponding fluences were used to determine the steady-state target sputtering yields of both uranium and uranium carbide, i.e. 6.3 atoms of uranium and 2.4 units of uranium carbide eroded per gallium ion, and 9.9 uranium atoms and 3.65 units of uranium carbide eroded by cesium ions. The steady state surface composition resulting from the simultaneous gallium or cesium implantation and sputter-erosion of uranium and uranium carbide were calculated to be U₈₆Ga₁₄, (UC)₇₀Ga₃₀ and U₈₁Cs₉, (UC)₇₉Cs₂₁, respectively.

  7. Quasi-periodic variations of cometary ion fluxes at large distances from comet Halley

    Energy Technology Data Exchange (ETDEWEB)

    Richter, A.K.; Daly, P.W.; Verigin, M.I.; Gringauz, K.I.; Erdos, G.; Kecskemety, K.; Somogyi, A.J.; Szego, K.; Varga, A.; McKenna-Lawlor, S.

    1989-04-01

    Large variations, with a period of about 4 h, in the energetic ion fluxes have been observed far upstream (between 2 and 10 million kilometers) of comet Halley on both the Vega-1 and Giotto spacecraft. We have fitted the cometocentric distances of the occurrences to a simple model of expanding shells of neutral particles, the production of which is modulated by the spin of the comet nucleus, and have achieved excellent agreement between the two spacecraft. We derive an expansion speed for the neutrals of 6.18 +- 0.14 km s/sup -1/. Possible candidates for the neutrals are hydrogen atoms, created by the photo-dissociation of OH with a speed of 8 km s/sup -1/, or oxygen atoms, produced from the photo-dissociation of CO/sub 2/ with a speed of 6.5 km s/sup -1/.

  8. Rotational spectrum of the molecular ion NH+ as a probe for α and me/mp variation

    International Nuclear Information System (INIS)

    Beloy, K.; Borschevsky, A.; Hauser, A. W.; Schwerdtfeger, P.; Kozlov, M. G.; Flambaum, V. V.

    2011-01-01

    We identify the molecular ion NH + as a potential candidate for probing variations in the fine-structure constant α and electron-to-proton mass ratio μ. NH + has an anomalously low-lying excited 4 Σ - state, being only a few hundred cm -1 above the ground 2 Π state. Being a light molecule, this proximity is such that rotational levels of the respective states are highly intermixed for low angular momenta. We find that several low-frequency transitions within the collective rotational spectrum experience enhanced sensitivity to α and μ variation. This is attributable to the close proximity of the 2 Π and 4 Σ - states, as well as the ensuing strong spin-orbit coupling between them. Suggestions that NH + may exist in interstellar space and recent predictions that trapped-ion precision spectroscopy will be adaptable to molecular ions make NH + a promising system for future astrophysical and laboratory studies of α and μ variation.

  9. Study on the variation of the distant crossing rice by ion beam implantation

    International Nuclear Information System (INIS)

    Wu Yuejin; Li Hong; Song Mei; Yu Zengliang; Wu Jingde; Tong Jiping; Zheng Leya

    2005-01-01

    The following contents including the original receptor EI213 and other two control materials, RAPD polymorphism, photosynthetic efficiency, and the number of vascular bundles of the first internodes below the peduncle have been studied for the eight F7 transgenic lines obtained from ion beam implantation. The results showed that there was a significant variation in genomes of maize-rice line, compared with the receptor EI213, after the total exogenous maize DNA was introduced into EI213. The number of the vascular bundles of maize-rich progeny's line was obviously much larger than those of the original receptor EI213 and other two controls GER-3 and MH63, and along with the photosynthetic efficiency of maize-rice progeny's lines being gone up. Moreover, the parenchyma cells around the vascular bundles of the transgenic lines became much larger in number and in size than those around the controls. All these indicated that the maize-rich progeny's lines are really different from and superior to the receptor and the controls. It is a novel and useful way to apply ion beam implantation in transferring DNA from C 4 plant maize into C 3 plant rice. (authors)

  10. Peripheral lymphocyte subset variation predicts prostate cancer carbon ion radiotherapy outcomes

    Science.gov (United States)

    Shi, Ze-Liang; Li, Bing-Xin; Wu, Xian-Wei; Li, Ping; Zhang, Qing; Wei, Xun-Bin; Fu, Shen

    2016-01-01

    The immune system plays a complementary role in the cytotoxic activity of radiotherapy. Here, we examined changes in immune cell subsets after heavy ion therapy for prostate cancer. The lymphocyte counts were compared with acute radiotherapy-related toxicity, defined according to the Common Terminology Criteria for Adverse Events, and short-term local efficacy, defined based on prostate-specific antigen concentrations. Confirmed prostate cancer patients who had not received previous radiotherapy were administered carbon ion radiotherapy (CIR) in daily fractions of 2.74 GyE with a total dose of 63-66 GyE. Lymphocyte subset counts were investigated before, during and after radiotherapy, and at a 1 month follow-up. Most notable among our findings, the CD4/CD8 ratio and CD19+ cell counts were consistently higher in patients with a complete response (CR) or partial response (PR) to CIR than in those classified in the stable disease (SD) group (P<0.05 for both). But CD3+ and CD8+ cell counts were lower in the CR and PR groups than in the SD group. These results indicate that variations in peripheral lymphocyte subpopulations are predictive of outcome after CIR for prostate cancer. PMID:27029063

  11. Effect of velocity variation on secondary-ion-emission probability: Quantum stationary approach

    International Nuclear Information System (INIS)

    Goldberg, E.C.; Ferron, J.; Passeggi, M.C.G.

    1989-01-01

    The ion-velocity dependence of the ionization probability for an atom ejected from a surface is examined by using a quantum approach in which the coupled motion between electrons and the outgoing nucleus is followed along the whole trajectory by solving the stationary Schroedinger equation. We choose a very-small-cluster-model system in which the motion of the atom is restricted to one dimension, and with energy potential curves corresponding to the involved channels varying appreciably with the atom position. We found an exponential dependence on the inverse of the asymptotic ion velocity for high emission energies, and a smoother behavior with slight oscillations at low energies. These results are compared with those obtained within a dynamical-trajectory approximation using either a constant velocity equal to the asymptotic ionic value, or expressions for the velocity derived from the eikonal approximation and from the classical limit of the current vector. Both approaches give similar results provided the velocity is allowed to adjust self-consistently to potential energies and transition-amplitude variations. Strong oscillations are observed in the low-emission-energy range either if the transitions are neglected, or a constant velocity along the whole path is assumed for the ejected particle

  12. Comparative analysis of long-time variations of multicomponent ion ring current according to data of geostationary Gorizont satellite

    International Nuclear Information System (INIS)

    Kovtyukh, A.S.; Panasyuk, M.I.; Vlasova, N.A.; Sosnovets, Eh.N.

    1990-01-01

    Long-time variations of the fluxes of the H + , [N,O] 2+ and [C,N,O] 6 6 + ions with energy E/Q∼60-120 keV/e measured by the GORIZONT (1985-07A) satellite in the geostationary orbit at noon time are analyzed. The results are dsicussed and are compared with current models of the formation of the Earth's ion ring current

  13. Distributions of neutron yields and doses around a water phantom bombarded with 290-MeV/nucleon and 430-MeV/nucleon carbon ions

    Energy Technology Data Exchange (ETDEWEB)

    Satoh, D., E-mail: satoh.daiki@jaea.go.jp [Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Kajimoto, T. [Hiroshima University, Kagamiyama, Higashi-Hiroshima-shi, Hiroshima 739-8527 (Japan); Shigyo, N.; Itashiki, Y.; Imabayashi, Y. [Kyushu University, Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Koba, Y.; Matsufuji, N. [National Institute of Radiological Sciences, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Sanami, T. [High Energy Accelerator Research Organization, Oho-cho, Tsukuba-shi, Ibaraki 305-0801 (Japan); Nakao, N. [Shimizu Corporation, Etchujima, Koto-ku, Tokyo 135-8530 (Japan); Uozumi, Y. [Kyushu University, Motooka, Nishi-ku, Fukuoka 819-0395 (Japan)

    2016-11-15

    Double-differential neutron yields from a water phantom bombarded with 290-MeV/nucleon and 430-MeV/nucleon carbon ions were measured at emission angles of 15°, 30°, 45°, 60°, 75°, and 90°, and angular distributions of neutron yields and doses around the phantom were obtained. The experimental data were compared with results of the Monte-Carlo simulation code PHITS. The PHITS results showed good agreement with the measured data. On the basis of the PHITS simulation, we estimated the angular distributions of neutron yields and doses from 0° to 180° including thermal neutrons.

  14. Negative-ion production on carbon materials in hydrogen plasma : influence of the carbon hybridization state and the hydrogen content on H- yield

    NARCIS (Netherlands)

    Ahmad, A.; Pardanaud, C.; Carrère, M.; Layet, J.M.; Gicquel, A.; Kumar, P.; Eon, D.; Jaoul, C.; Engeln, R.A.H.; Cartry, G.

    2014-01-01

    Highly oriented polycrystalline graphite (HOPG), boron-doped diamond (BDD), nanocrystalline diamond, ultra-nanocrystalline diamond and diamond-like carbon surfaces are exposed to low-pressure hydrogen plasma in a 13.56 MHz plasma reactor. Relative yields of surface-produced H- ions due to

  15. Intraspecific Variation in Wood Anatomical, Hydraulic, and Foliar Traits in Ten European Beech Provenances Differing in Growth Yield

    Science.gov (United States)

    Hajek, Peter; Kurjak, Daniel; von Wühlisch, Georg; Delzon, Sylvain; Schuldt, Bernhard

    2016-01-01

    In angiosperms, many studies have described the inter-specific variability of hydraulic-related traits and little is known at the intra-specific level. This information is however mandatory to assess the adaptive capacities of tree populations in the context of increasing drought frequency and severity. Ten 20-year old European beech (Fagus sylvatica L.) provenances representing the entire distribution range throughout Europe and differing significantly in aboveground biomass increment (ABI) by a factor of up to four were investigated for branch wood anatomical, hydraulic, and foliar traits in a provenance trial located in Northern Europe. We quantified to which extend xylem hydraulic and leaf traits are under genetic control and tested whether the xylem hydraulic properties (hydraulic efficiency and safety) trades off with yield and wood anatomical and leaf traits. Our results showed that only three out of 22 investigated ecophysiological traits showed significant genetic differentiations between provenances, namely vessel density (VD), the xylem pressure causing 88% loss of hydraulic conductance and mean leaf size. Depending of the ecophysiological traits measured, genetic differentiation between populations explained 0–14% of total phenotypic variation, while intra-population variability was higher than inter-population variability. Most wood anatomical traits and some foliar traits were additionally related to the climate of provenance origin. The lumen to sapwood area ratio, vessel diameter, theoretical specific conductivity and theoretical leaf-specific conductivity as well as the C:N-ratio increased with climatic aridity at the place of origin while the carbon isotope signature (δ13C) decreased. Contrary to our assumption, none of the wood anatomical traits were related to embolism resistance but were strong determinants of hydraulic efficiency. Although ABI was associated with both VD and δ13C, both hydraulic efficiency and embolism resistance were

  16. Variation of yield loci in finite element analysis by considering texture evolution for AA5042 aluminum sheets

    Science.gov (United States)

    Yoon, Jonghun; Kim, Kyungjin; Yoon, Jeong Whan

    2013-12-01

    Yield function has various material parameters that describe how materials respond plastically in given conditions. However, a significant number of mechanical tests are required to identify the many material parameters for yield function. In this study, an effective method using crystal plasticity through a virtual experiment is introduced to develop the anisotropic yield function for AA5042. The crystal plasticity approach was used to predict the anisotropic response of the material in order to consider a number of stress or strain modes that would not otherwise be evident through mechanical testing. A rate-independent crystal plasticity model based on a smooth single crystal yield surface, which removes the innate ambiguity problem within the rate-independent model and Taylor model for polycrystalline deformation behavior were employed to predict the material's response in the balanced biaxial stress, pure shear, and plane strain states to identify the parameters for the anisotropic yield function of AA5042.

  17. The Effect of Solar Wind Variations on the Escape of Oxygen Ions From Mars Through Different Channels: MAVEN Observations

    Science.gov (United States)

    Dubinin, E.; Fraenz, M.; Pätzold, M.; McFadden, J.; Halekas, J. S.; DiBraccio, G. A.; Connerney, J. E. P.; Eparvier, F.; Brain, D.; Jakosky, B. M.; Vaisberg, O.; Zelenyi, L.

    2017-11-01

    We present multi-instrument observations of the effects of solar wind on ion escape fluxes on Mars based on the Mars Atmosphere and Volatile EvolutioN (MAVEN) data from 1 November 2014 to 15 May 2016. Losses of oxygen ions through different channels (plasma sheet, magnetic lobes, boundary layer, and ion plume) as a function of the solar wind and the interplanetary magnetic field variations were studied. We have utilized the modified Mars Solar Electric (MSE) coordinate system for separation of the different escape routes. Fluxes of the low-energy (≤30 eV) and high-energy (≥30 eV) ions reveal different trends with changes in the solar wind dynamic pressure, the solar wind flux, and the motional electric field. Major oxygen fluxes occur through the tail of the induced magnetosphere. The solar wind motional electric field produces an asymmetry in the ion fluxes and leads to different relations between ion fluxes supplying the tail from the different hemispheres and the solar wind dynamic pressure (or flux) and the motional electric field. The main driver for escape of the high-energy oxygen ions is the solar wind flux (or dynamic pressure). On the other hand, the low-energy ion component shows the opposite trend: ion flux decreases with increasing solar wind flux. As a result, the averaged total oxygen ion fluxes reveal a low variability with the solar wind strength. The large standard deviations from the averages values of the escape fluxes indicate the existence of mechanisms which can enhance or suppress the efficiency of the ion escape. It is shown that the Martian magnetosphere possesses the properties of a combined magnetosphere which contains different classes of field lines. The existence of the closed magnetic field lines in the near-Mars tail might be responsible for suppression of the ion escape fluxes.

  18. Product ion diffusion in flowing afterglows

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, M J; Stock, H M.P. [University Coll. of Wales, Aberystwyth (UK). Dept. of Physics

    1975-11-11

    An analysis of the variation of product ion signals in flowing after-glow experiments is presented. It is shown that under certain conditions the relative variation of a single product ion yields not only the total reaction rate coefficients but also the ambipolar diffusion coefficient of the product ion in the buffer gas. Theory is compared with experiment for a number of ion-molecule and Penning reactions.

  19. Color matters--material ejection and ion yields in UV-MALDI mass spectrometry as a function of laser wavelength and laser fluence.

    Science.gov (United States)

    Soltwisch, Jens; Jaskolla, Thorsten W; Dreisewerd, Klaus

    2013-10-01

    The success of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) as a widely employed analytical tool in the biomolecular sciences builds strongly on an effective laser-material interaction that is resulting in a soft co-desorption and ionization of matrix and imbedded biomolecules. To obtain a maximized ion yield for the analyte(s) of interest, in general both wavelength and fluence need to be tuned to match the specific optical absorption profile of the used matrix. However, commonly only lasers with fixed emission wavelengths of either 337 or 355 nm are used for MALDI-MS. Here, we employed a wavelength-tunable dye laser and recorded both the neutral material ejection and the MS ion data in a wide wavelength and fluence range between 280 and 377.5 nm. α-Cyano-4-hydroxycinnamic acid (HCCA), 4-chloro-α-cyanocinnamic acid (ClCCA), α-cyano-2,4-difluorocinnamic acid (DiFCCA), and 2,5-dihydroxybenzoic acid (DHB) were investigated as matrices, and several peptides as analytes. Recording of the material ejection was achieved by adopting a photoacoustic approach. Relative ion yields were derived by division of photoacoustic and ion signals. In this way, distinct wavelength/fluence regions can be identified for which maximum ion yields were obtained. For the tested matrices, optimal results were achieved for wavelengths corresponding to areas of high optical absorption of the respective matrix and at fluences about a factor of 2-3 above the matrix- and wavelength-dependent ion detection threshold fluences. The material ejection as probed by the photoacoustic method is excellently fitted by the quasithermal model, while a sigmoidal function allows for an empirical description of the ion signal-fluence relationship.

  20. The reduction of the change of secondary ions yield in the thin SiON/Si system

    International Nuclear Information System (INIS)

    Sameshima, J.; Yamamoto, H.; Hasegawa, T.; Nishina, T.; Nishitani, T.; Yoshikawa, K.; Karen, A.

    2006-01-01

    For the analyses of gate insulating materials of thin silicon oxy-nitride (SiON) and dielectric films, SIMS is one of the available tool along with TEM and ESCA, etc. Especially, to investigate the distribution of dopant in the thin films, SIMS is appreciably effective in these techniques because of its depth profiling capability and high sensitivity. One of the problem occurring in this SIMS measurement is the change of secondary ion yield at the interface as well as in the layers with different chemical composition. To solve this problem, some groups have researched the phenomenon for SiO 2 /Si interface [W. Vandervorst, T. Janssens, R. Loo, M. Caymax, I. Peytier, R. Lindsay, J. Fruhauf, A. Bergmaier, G. Dollinger, Appl. Surf. Sci. 203-204 (2003) 371-376; S. Hayashi, K.Yanagihara, Appl. Surf. Sci. 203-204 (2003) 339-342; M. Barozzi, D. Giubertoni, M.Anderle, M. Bersani, Appl. Surf. Sci. 231-232 (2004) 632-635; T.H. Buyuklimanli, J.W. Marino, S.W. Novak, Appl. Surf. Sci. 231-232 (2004) 636-639]. In the present study, profiles of boron and matrix elements in the Si/SiON layers on Si substrate have been investigated. The sensitivity change of Si and B profiles in SiON layer become smaller by using oxygen flood than those without oxygen flood for both O 2 + and Cs + beam. At the range of 0-25 at.% of N composition, 11 B dosimetry in SiON layer implanted through amorphous Si depends on N composition. This trend could be caused by the sensitivity change of 11 B, or it indicates real 11 B concentration change in SiON lyaer. N areal density determined by Cs + SIMS with oxygen flooding also shows linear relationship with N composition estimated by XPS

  1. Variation on biomass yield and morphological traits of energy grasses from the genus Miscanthus during the first years of crop establishment

    Energy Technology Data Exchange (ETDEWEB)

    Jezowski, S.; Glowacka, K.; Kaczmarek, Z. [Institute of Plant Genetics, Polish Academy of Sciences, ul. Strzeszynska 34, 60-479 Poznan (Poland)

    2011-02-15

    This study presents the results of investigations of variation, genotype x year interactions and genotype x year x location interactions for the yield and morphological traits of several selected clones of energy grasses of the genus Miscanthus. The analyses were performed on the best clones of selected hybrid plants, which were obtained within the species M. sinensis or are the result of interspecific hybridization of M. sinensis and M. sacchariflorus. Analyses were conducted on the basis of three-year field trials at two locations. The young plants produced from in vitro cultures were planted at a density of one plant per m{sup 2}. The early stages of plant development, from planting until peak yield in the third year of cultivation, were analysed. Statistical analyses performed on the yield and morphological traits as well as changes in these characteristics over the successive years of the study showed considerable genotypic variation for traits under study. Moreover, significant genotype x year interactions as well as genotype x year x location interactions were observed in terms of yield and morphological traits. Based on the collective results of the study, we suggest that apart from M. x giganteus particularly hybrids of M. sinensis x M. sacchariflorus, should be taken into consideration in genetic and breeding studies on the improvement of yield from energy grasses of the genus Miscanthus. (author)

  2. Changes in growth and yield characters and in genetic variation of peanut (Arachis hypogaea L.) plants due to gamma ray irradiation

    International Nuclear Information System (INIS)

    Kassem, M.; Esawy, W.A.

    2003-01-01

    Air dried seeds of two peanut cultivars Giza 4 and Giza 5 were subjected to irradiation treatments of Co 6 0 gamma ray doses i.e. 0, 100, 150, 200, 250 Gy to study their effect on growth characters, yield components, genetic variation, heritability and genetic advance for election; during 2000 and 2001 summer seasons. Results indicated that, the 100 Gy treatment produced the highest means of most growth characters in M 1 and M 2 generations, however the 250 Gy treatment produced the highest means for No. of pods/plant, pod yield/plant, seed yield/plant and shelling percentage in M 1 generation, but the 200 Gy treatment produced the highest means of yield components in M 2 generation for the two cultivars Giza 4 Giza 5. In general, mean percentages of oil and protein were decreased by increasing gamma ray doses in M 1 and M 2 generations for both Giza 4 and Giza 5. The highest estimates of phenotypic and genotypic coefficient of variation, heritability and genetic advance under selection were obtained with 250 Gy dose for most growth characters and yield components as well as oil and protein percentages of the two cultivars in both M 1 and M 2 generations

  3. Statistical evaluation of fuel yield and morphological variates for some promising energy plantation tree species in western Rajasthan

    Energy Technology Data Exchange (ETDEWEB)

    Kalla, J.C.

    1977-01-01

    Stepwise regression analysis suggested that tree height and collar diameter were, in general, the morphological parameters that most reliably predicted fuel yield in Acacia nilotica, A. tortilis, Albizzia lebbek, Azadirachta indica and Prosopis juliflora.

  4. Water soluble ions in aerosols (TSP) : Characteristics, sources and seasonal variation over the central Himalayas, Nepal

    Science.gov (United States)

    Tripathee, Lekhendra; Kang, Shichang; Zhang, Qianggong; Rupakheti, Dipesh

    2016-04-01

    Atmspheric pollutants transported from South Asia could have adverse impact on the Himalayan ecosystems. Investigation of aerosol chemistry in the Himalayan region in Nepal has been limited on a temporal and spatial scale to date. Therefore, the water-soluble ionic composition of aerosol using TSP sampler was investigated for a year period from April 2013 to March 2014 at four sites Bode, Dhunche, Lumbini and Jomsom characterized as an urban, rural, semi-urban and remote sites in Nepal. During the study period, the highest concentration of major cation was Ca2+ with an average concentration of 8.91, 2.17, 7.85 and 6.42 μg m-3 and the highest concentration of major anion was SO42- with an average of 10.96, 4.06, 6.85 and 3.30 μg m-3 at Bode, Dhunche, Lumbini and Jomsom respectively. The soluble ions showed the decrease in concentrations from urban to the rural site. Correlations and PCA analysis suggested that that SO42-, NO3- and NH4+ were derived from the anthropogenic sources where as the Ca2+ and Mg2+ were from crustal sources. Our results also suggest that the largest acid neutralizing agent at our sampling sites in the central Himalayas are Ca2+ followed by NH4+. Seasonal variations of soluble ions in aerosols showed higher concentrations during pre-monsoon and winter (dry-periods) due to limited precipitation amount and lower concentrations during the monsoon which can be explained by the dilution effect, higher the precipitation lower the concentration. K+ which is regarded as the tracer of biomss burning had a significant peaks during pre-monsoon season when the forest fires are active around the regions. In general, the results of this study suggests that the atmospheric chemistry is influenced by natural and anthropogenic sources. Thus, soluble ionic concentrations in aerosols from central Himalayas, Nepal can provide a useful database to assess atmospheric environment and its impacts on human health and ecosystem in the southern side of central

  5. Geotail observations of plasma sheet ion composition over 16 years: On variations of average plasma ion mass and O+ triggering substorm model

    Science.gov (United States)

    Nosé, M.; Ieda, A.; Christon, S. P.

    2009-07-01

    We examined long-term variations of ion composition in the plasma sheet, using energetic (9.4-212.1 keV/e) ion flux data obtained by the suprathermal ion composition spectrometer (STICS) sensor of the energetic particle and ion composition (EPIC) instrument on board the Geotail spacecraft. EPIC/STICS observations are available from 17 October 1992 for more than 16 years, covering the declining phase of solar cycle 22, all of solar cycle 23, and the early phase of solar cycle 24. This unprecedented long-term data set revealed that (1) the He+/H+ and O+/H+ flux ratios in the plasma sheet were dependent on the F10.7 index; (2) the F10.7 index dependence is stronger for O+/H+ than He+/H+; (3) the O+/H+ flux ratio is also weakly correlated with the ΣKp index; and (4) the He2+/H+ flux ratio in the plasma sheet appeared to show no long-term trend. From these results, we derived empirical equations related to plasma sheet ion composition and the F10.7 index and estimated that the average plasma ion mass changes from ˜1.1 amu during solar minimum to ˜2.8 amu during solar maximum. In such a case, the Alfvén velocity during solar maximum decreases to ˜60% of the solar minimum value. Thus, physical processes in the plasma sheet are considered to be much different between solar minimum and solar maximum. We also compared long-term variation of the plasma sheet ion composition with that of the substorm occurrence rate, which is evaluated by the number of Pi2 pulsations. No correlation or negative correlation was found between them. This result contradicts the O+ triggering substorm model, in which heavy ions in the plasma sheet increase the growth rate of the linear ion tearing mode and play an important role in localization and initiation of substorms. In contrast, O+ ions in the plasma sheet may prevent occurrence of substorms.

  6. How do air ions reflect variations in ionising radiation in the lower atmosphere in a boreal forest?

    Directory of Open Access Journals (Sweden)

    X. Chen

    2016-11-01

    Full Text Available Most of the ion production in the atmosphere is attributed to ionising radiation. In the lower atmosphere, ionising radiation consists mainly of the decay emissions of radon and its progeny, gamma radiation of the terrestrial origin as well as photons and elementary particles of cosmic radiation. These types of radiation produce ion pairs via the ionisation of nitrogen and oxygen as well as trace species in the atmosphere, the rate of which is defined as the ionising capacity. Larger air ions are produced out of the initial charge carriers by processes such as clustering or attachment to pre-existing aerosol particles. This study aimed (1 to identify the key factors responsible for the variability in ionising radiation and in the observed air ion concentrations, (2 to reveal the linkage between them and (3 to provide an in-depth analysis into the effects of ionising radiation on air ion formation, based on measurement data collected during 2003–2006 from a boreal forest site in southern Finland. In general, gamma radiation dominated the ion production in the lower atmosphere. Variations in the ionising capacity came from mixing layer dynamics, soil type and moisture content, meteorological conditions, long-distance transportation, snow cover attenuation and precipitation. Slightly similar diurnal patterns to variations in the ionising capacity were observed in air ion concentrations of the cluster size (0.8–1.7 nm in mobility diameters. However, features observed in the 0.8–1 nm ion concentration were in good connection to variations of the ionising capacity. Further, by carefully constraining perturbing variables, a strong dependency of the cluster ion concentration on the ionising capacity was identified, proving the functionality of ionising radiation in air ion production in the lower atmosphere. This relationship, however, was only clearly observed on new particle formation (NPF days, possibly indicating that charges after

  7. Variations in Volatile Oil Yield and Composition of "Xin-yi" (Magnolia biondii Pamp. Flower Buds) at Different Growth Stages.

    Science.gov (United States)

    Hu, Mingli; Bai, Mei; Ye, Wei; Wang, Yaling; Wu, Hong

    2018-06-01

    Dried flower buds of Magnolia biondii Pamp. are the main ingredient in "Xin-yi" in China, and the volatile oils of M. biondii flower buds are the principal medicinal component. Gas chromatographymass spectrometry (GC-MS) and microscopic techniques were employed to detect the volatile yields of M. biondii flowers at various growth stages. The volatile oil yields of M. biondii flowers differed significantly at different growth stages and were closely related to flower dry weight, oil cell density and degree of oil accumulation. In February 2016, flower buds had the highest dry weight, the maximum percentage of oil cells at the oil saturation stage and the highest density of oil cells, which coincided with the highest oil yield. In March 2016, flower buds had a lower dry weight, a higher percentage of oil cells at the oil-degrading stage and the lowest oil cell density, resulting in decreased oil yields. The total amounts of the major medicinal components in the M. biondii flower also showed regular changes at different growth stages. In January and February of 2016, M. biondii flowers had a higher dry weight, volatile oil yield and total content of medicinal ingredients, which was the best time for harvesting high-quality medicinal components. Our study reveals that volatile oil content and chemical composition are closely related to the growth stage of M. biondii flower buds. The results provide a scientific morphology and composition index for evaluating the medicinal value and harvesting of high-quality M. biondii medicinal herbs.

  8. The comparative study on screening of pleurotus polysaccharide high-yield strains by use of ion beam implantation and composite mutagenesis

    International Nuclear Information System (INIS)

    Wang Lianfeng; Chen Henglei; Zhang Jun; Zeng Xianxian

    2009-01-01

    In order to screen pleurotus mycelium polysaccharide high-yield strains, the comparative study was made by use of ion beam implantation and composite mutagenesis before screening. The treating mycelium pellet of pleurotus ferulae tentatively with ion beam implantation was performed at the first. Two polysaccharide high-yield strains, PFPH-1and PFPH-2, were selected using fermentation quantitative screening after auxotrophy qualitative primary screening. It has been found that the polysaccharide yield of the mutants is 551.80mg/L and 659.46mg/L respectively,which increases by 46.55% and 75.14% respectively compared to that of initial strain. Then PFPH-1and PFPH-2, as the original strain, is exposed to ultraviolet light and is suffered by additive of LiCl respectively. The results indicate that the polysaccharide yield of strains 1,9 and 10 decreases by 27%, 38% and 37% respectively compared to that of PFPH-1 meanwhile the polysaccharide yield of strain 17 decreases by 28% compared to that of PFPH-2 after high-flux qualitative primary screening. In this study, composite mutagenesis with exposure of ultra-violet and additive of lithium chloride shows some negative effects. (authors)

  9. Evaluation of secondary ion yield enhancement from polymer material by using TOF-SIMS equipped with a gold cluster ion source

    Energy Technology Data Exchange (ETDEWEB)

    Aimoto, K. [Department of Applied Physics, Faculty of Engineering, Seikei University, 3-3-1 Kichijioji-Kitamachi, Musashino-shi, Tokyo 180-8633 (Japan)]. E-mail: dm053502@cc.seikei.ac.jp; Aoyagi, S. [Department of Regional Development, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu-cho, Matsue-shi, Shimane 690-8504 (Japan); Kato, N. [Department of Applied Physics, Faculty of Engineering, Seikei University, 3-3-1 Kichijioji-Kitamachi, Musashino-shi, Tokyo 180-8633 (Japan); Iida, N. [ULVAC-PHI, Inc., 370 Enzo, Chigasaki, Kanagawa 253-0084 (Japan); Yamamoto, A. [ULVAC-PHI, Inc., 370 Enzo, Chigasaki, Kanagawa 253-0084 (Japan); Kudo, M. [Department of Applied Physics, Faculty of Engineering, Seikei University, 3-3-1 Kichijioji-Kitamachi, Musashino-shi, Tokyo 180-8633 (Japan)

    2006-07-30

    We investigated the enhancement of the secondary ion intensity in the TOF-SIMS spectra obtained by Au{sup +} and Au{sub 3} {sup +} bombardment in comparison with Ga{sup +} excitation using polymer samples with different molecular weight distributions. Since the polymer samples used in this experiment have a wide molecular weight distribution, the advantages of the gold cluster primary ion source over monoatomic ion could accurately be evaluated. It was observed that the degree of fragmentation decreased by the usage of cluster primary ion beam compared with monoatomic ion beam, which was observed as a shift of the intensity distribution in the spectra. It was also found out that the mass effect of Au{sup +} and Ga{sup +} as monoatomic primary ion, resulted in about 10-60 times of enhancement for both samples with different molecular distributions. On the other hand, the Au{sub 3} {sup +} bombardment caused intensity enhancement about 100-2600 compared with Ga{sup +} bombardment, depending on the mass range of the detected secondary ion species. The cluster primary ion effect of Au{sub 3} {sup +}, compared with Au{sup +}, therefore, was estimated to be about 10-45.

  10. Causes of variation among rice models in yield response to CO2 examined with Free-Air CO2 Enrichment and growth chamber experiments.

    Science.gov (United States)

    Hasegawa, Toshihiro; Li, Tao; Yin, Xinyou; Zhu, Yan; Boote, Kenneth; Baker, Jeffrey; Bregaglio, Simone; Buis, Samuel; Confalonieri, Roberto; Fugice, Job; Fumoto, Tamon; Gaydon, Donald; Kumar, Soora Naresh; Lafarge, Tanguy; Marcaida Iii, Manuel; Masutomi, Yuji; Nakagawa, Hiroshi; Oriol, Philippe; Ruget, Françoise; Singh, Upendra; Tang, Liang; Tao, Fulu; Wakatsuki, Hitomi; Wallach, Daniel; Wang, Yulong; Wilson, Lloyd Ted; Yang, Lianxin; Yang, Yubin; Yoshida, Hiroe; Zhang, Zhao; Zhu, Jianguo

    2017-11-01

    The CO 2 fertilization effect is a major source of uncertainty in crop models for future yield forecasts, but coordinated efforts to determine the mechanisms of this uncertainty have been lacking. Here, we studied causes of uncertainty among 16 crop models in predicting rice yield in response to elevated [CO 2 ] (E-[CO 2 ]) by comparison to free-air CO 2 enrichment (FACE) and chamber experiments. The model ensemble reproduced the experimental results well. However, yield prediction in response to E-[CO 2 ] varied significantly among the rice models. The variation was not random: models that overestimated at one experiment simulated greater yield enhancements at the others. The variation was not associated with model structure or magnitude of photosynthetic response to E-[CO 2 ] but was significantly associated with the predictions of leaf area. This suggests that modelled secondary effects of E-[CO 2 ] on morphological development, primarily leaf area, are the sources of model uncertainty. Rice morphological development is conservative to carbon acquisition. Uncertainty will be reduced by incorporating this conservative nature of the morphological response to E-[CO 2 ] into the models. Nitrogen levels, particularly under limited situations, make the prediction more uncertain. Improving models to account for [CO 2 ] × N interactions is necessary to better evaluate management practices under climate change.

  11. L-shell x-ray yields and production cross-sections of molybdenum induced by low-energy highly charged argon ions

    International Nuclear Information System (INIS)

    Du Juan; Xu Jinzhang; Chen Ximeng; Yang Zhihu; Shao Jianxiong; Cui Ying; Zhang Hongqiang; Gao Zhimin; Liu Yuwen

    2007-01-01

    L-shell x-ray yields of molybdenum bombarded by highly charged Ar q+ ions (q=11-16) are measured. The x-ray production cross-sections are extracted from the yields data. The energy of the incident Ar ions ranges from 200 to 350 keV. After the binding energy correction, experimental data are explained in the framework of binary-encounter-approximation (BEA). The direct ionization is treated in the united atom (UA) limit (Lapicki and Lichten 1985 Phys. Rev. A 31 1354), not in the separate atom (SA) limit. The calculation results of BEA (Gacia and Fortner 1973 Rev. Mod. Phys. 45 111) are much lower than the experimental results, while the results of binding energy modified BEA are basically in agreement with the experimental results

  12. Maize yield response to nitrogen as influenced by spatio-temporal variations of soil-water-topography dynamics

    Science.gov (United States)

    Reducing N loss from agricultural lands and applying N fertilizer at rates that satisfy both economic and environmental objectives is critical for sustainable agricultural management. This study investigated spatial variability in maize yield response to N and its controlling factors along a typical...

  13. Kinetics of methane fermentation yield in biogas reactors: Genetic variation and association with chemical composition in maize

    International Nuclear Information System (INIS)

    Grieder, Christoph; Mittweg, Greta; Dhillon, Baldev S.; Montes, Juan M.; Orsini, Elena; Melchinger, Albrecht E.

    2012-01-01

    Maize (Zea mays L.) is the most competitive crop for methane production in Germany. Methane fermentation yield per unit of dry matter (MFY) is a determinant of methane yield, but little information is available on this trait. Our objectives were to investigate the kinetics of MFY during fermentation of maize, estimate quantitative-genetic parameters for different traits related to MFY and examine the relationship of MFY with chemical composition and silage quality. Whole-plant material of 16 inbreds and their 32 testcrosses was analyzed for MFY over 35 days of fermentation using a discontinuous laboratory assay. Data were also generated on chemical composition and in vitro digestible organic matter (IVDOM). Significant genotypic variances and high heritabilities were observed for MFY at early fermentation stages (up to 5 days) probably due to different concentrations of easily degradable chemical components. However, genotypic variances and heritability of MFY reduced as fermentation progressed, because of complete or partial degradation of all chemical components. Further, there were strong correlations of MFY with chemical components at early fermentation stages but not at later stages. Therefore, MFY at later stages, which is closer to potential MFY, does not seem to be amenable to selection. High heritability of IVDOM and its strong correlation with MFY in testcrosses indicated its possible use for preliminary or indirect selection. Keeping in view the magnitude of genetic variance that was low for MFY and high for dry matter yield (DMY), the other component of methane yield, more emphasis on breeding for DMY seems appropriate. -- Highlights: ► We investigated methane fermentation yield (MFY) of diverse germplasm of maize. ► The kinetics of MFY and its correlations with chemical composition were examined. ► Genetic variance and heritability for MFY decreased with fermentation time. ► Complete fermentation (35 d) reduced correlations of MFY with chemical

  14. Genetic variation for seed yield and some of agro-morphological traits in faba bean (Vicia faba L. genotypes

    Directory of Open Access Journals (Sweden)

    Peyman SHARIFI

    2015-11-01

    Full Text Available  An investigation was carried out to select the most successful faba bean genotype(s and to estimate the heritability for seed yield and some of agro-morphological traits. The results of analysis of variance indicated that the studied genotypes differed significantly for all of the traits. For 100-seed weight, two north's of Iran landraces (G1 and G2 and two improved breeding cultivars containing France (G4 and Barrakat (G10 possessed the heaviest seed weight, 161.33, 139, 119.67 and 166 g, respectively. G1 and G10 presented the highest values for dry seed weight (473.98 and 495.44 g m-2, respectively. G1 and G10 showed significantly higher magnitude values of the other traits. Broad sense heritability (h2 estimates were generally high to moderate for all of the studied traits. The highest estimates of broad sense heritability was inscribed as 98 % for pod length, dry seed length and dry seed width and 0.95 for hundred seed weight. The estimated broad-sense heritability was 0.80 for dry seed yield per m2. These results suggested that the environmental factors had a small effect on the inheritance of traits with high heritability. High estimates of heritability indicated that selection based on mean would be successful in improving of these traits. High heritability indicate an additive gene action for the traits, and hence, possible trait improvement through selection. Path coefficient analysis indicated that the traits containing day to harvesting, pod length, hundred seed weight and number of stems per plant play major role in seed yield determination of faba bean. Attention should be paid to these characters for augmentation of seed yield and these traits could be used as selection criteria in faba bean breeding programs. These findings indicate that selection for each or full of the above traits would be accompanied by high yielding ability under such conditions. 

  15. Ion-stimulated Gas Desorption Yields of Electropolished, Chemically Etched, and Coated (Au, Ag, Pd, TiZrV) Stainless Steel Vacuum Chambers and St707 Getter Strips Irradiated with 4.2 MeV/u lead ions

    CERN Document Server

    Mahner, E; Küchler, D; Malabaila, M; Taborelli, M

    2005-01-01

    The ion-induced desorption experiment, installed in the CERN Heavy Ion Accelerator LINAC 3, has been used to measure molecular desorption yields for 4.2 MeV/u lead ions impacting under grazing incidence on different accelerator-type vacuum chambers. Desorption yields for H2, CH4, CO, and CO2, which are of fundamental interest for future accelerator applications, are reported for different stainless steel surface treatments. In order to study the effect of the surface oxide layer on the gas desorption, gold-, silver-, palladium-, and getter-coated 316 LN stainless steel chambers and similarly prepared samples were tested for desorption at LINAC 3 and analysed for chemical composition by X-ray Photoemission Spectroscopy (XPS). The large effective desorption yield of 2 x 104 molecules/Pb53+ ion, previously measured for uncoated, vacuum fired stainless steel, was reduced after noble-metal coating by up to 2 orders of magnitude. In addition, pressure rise measurements, the effectiveness of beam scrubbing with le...

  16. Variation and balance of positive air ion concentrations in a boreal forest

    Directory of Open Access Journals (Sweden)

    U. Hõrrak

    2008-02-01

    Full Text Available Air ions are characterized on the basis of measurements carried out in a boreal forest at the Hyytiälä SMEAR station, Finland, during the BIOFOR III campaign in spring 1999. The air ions were discriminated as small ions (charged molecular aggregates of the diameter of less than 2.5 nm, intermediate ions (charged aerosol particles of the diameter of 2.5–8 nm, and large ions (charged aerosol particles of the diameter of 8–20 nm. Statistical characteristics of the ion concentrations and the parameters of ion balance in the atmosphere are presented separately for the nucleation event days and non-event days. In the steady state, the ionization rate is balanced with the loss of small ions, which is expressed as the product of the small ion concentration and the ion sink rate. The widely known sinks of small ions are the recombination with small ions of opposite polarity and attachment to aerosol particles. The dependence of small ion concentration on the concentration of aerosol particles was investigated applying a model of the bipolar diffusion charging of particles by small ions. When the periods of relative humidity above 95% and wind speed less than 0.6 m s−1 were excluded, then the small ion concentration and the theoretically calculated small ion sink rate were closely negatively correlated (correlation coefficient −87%. However, an extra ion loss term of the same magnitude as the ion loss onto aerosol particles is needed for a quantitative explanation of the observations. This term is presumably due to the small ion deposition on coniferous forest. The hygroscopic growth correction of the measured aerosol particle size distributions was also found to be necessary for the proper estimation of the ion sink rate. In the case of nucleation burst events, the concentration of small positive ions followed the general balance equation, no extra ion loss in addition to the deposition on coniferous forest was detected, and the

  17. Development of methodics for the characterization of the composition of the ion-collision-induced secondary-particle flux by comparison of the yield contributions of photoinduced ion formation processes

    International Nuclear Information System (INIS)

    Vering, Guido

    2008-01-01

    The aim of this work was to develop a method to distinguish between different ion formation processes and to determine the influence of these processes on the total number of detected monatomic ions of a certain element. A vector/matrix-formalism was developed, which describes the physical processes of sputtering, ion formation, mass separation and detection in laser-SNMS. In the framework of the method developed, based on this theoretic formalism, changes in the secondary flux contribution of the respective element were observed by comparing the detected monatomic ion yield obtained in specifically aligned (SIMS and) laser-SNMS experiments. The yields resulting from these experiments were used to calculate characteristic numbers to compare the flux composition from different surfaces. The potential of the method was demonstrated for the elements boron, iron and gadolinium by investigating the changes in the flux composition of secondary particles sputtered from metallic surfaces, as a function of the oxygen concentration at the surface. Finally, combined laser-SNMS depth profiles and images, obtained with both laser systems, were presented to demonstrate how the parallel detection of the three differently originated ion signals of the same element can be used to get additional information about the composition of the flux of secondary particles synchronously during the analysis of elemental distributions. In this respect the presented method can be a very helpful tool to prevent misleading interpretations of SIMS or laser-SNMS data. (orig.)

  18. Simulating the effects of site index variation within loblolly pine plantations using an individual tree growth and yield model

    Science.gov (United States)

    Ralph L. Amateis; Harold E. Burkhart

    2016-01-01

    Site index is the most common metric of site productivity in loblolly pine plantations. Generally applied as a constant for a particular stand, it provides an overall measure of a site’s ability to grow trees. It is well known, however, that even the most uniform stands can have considerable variation in site index due to soil factors that influence microsite,...

  19. Genetic variations in the dynamics of dry matter accumulation, nitrogen assimilation and translocation in new T. aestivum L. varieties. I. Dynamics of dry matter accumulation. Grain yield and structural elements of yield

    International Nuclear Information System (INIS)

    Kostadin, K.; Nonkova, M.; Penchev, E.

    1999-01-01

    The genotype peculiarities in the translocation dynamics of dry matter in relation to wheat yield were studied under vegetation-laboratory and field conditions. The new wheat varieties Enola, Karat and Svilena created at the Institute for Wheat and Sunflower 'Dobroudja' have a high production potential due to their high intensity of dry matter accumulation in grain during the second half of maturation. It was established that in the standard variety Pliska the intensity of dry matter accumulation in reproductive parts was higher during heading-grain filling and then sharply decreased during maturation. This variety was characterized with high translocation of vegetation mass eventually leading to grain yield decrease. Significant genotype variations were established in the vegetation mass translocation in the respective parts during the stages of development. The contribution of the individual organs concerning carbohydrate reutilization to grain was mainly due to stems. An especially important peculiarity of the leaves of cv. Svilena was established: they ensured over 30 of grain yield at optimal nutrition. The complex evaluation of the new varieties revealed their high plasticity, the cultivar Karat showing the best characteristics. Refs. 13 (author)

  20. Average energetic ion flux variations associated with geomagnetic activity from EPIC/STICS on Geotail

    Science.gov (United States)

    Christon, S. P.; Gloeckler, G.; Eastman, T. E.; McEntire, R. W.; Roelef, E. C.; Lui, A. T. Y.; Williams, D. J.; Frank, L. A.; Paterson, W. R.; Kokubun, S.; hide

    1996-01-01

    The magnetotail ion flux measurements from the Geotail spacecraft are analyzed both with and without the application of selection criteria that identify the plasma regime in which an observation is obtained. The different results are compared with each other. The initial results on the changes of energetic ion flux and composition correlated to average substorm activity in different magnetotail plasma regimes are discussed. The energetic ions are measured using the energetic particles and ion composition (EPIC) experiment and the suprathermal ion composition spectrometer (STICS). The plasma, wave and field instruments of the Geotail satellite were used to identify the principle magnetotail plasma regimes of plasma sheet, lobe, and magnetospheric boundary layer, as well as the magnetosheath and solar wind. Energetic O and H ions were observed in all the plasma regimes.

  1. Improvement of the yield of highly charged ions by a gas-pulsing technique and the current status of the NIRS Penning source

    International Nuclear Information System (INIS)

    Miyata, Tomohiro; Miyoshi, Tomohiro; Sakuma, Tetsuya; Yamamoto, Mitsugu; Kitagawa, Atsushi; Muramatsu, Masayuki; Sato, Yukio

    2004-01-01

    The yields of highly charged ions have been improved by using a gas-pulsing technique in the pulsed Penning-ionized-gauge ion source (PIGIS) in the heavy-ion medical accelerator in Chiba. So far, this pulsed PIGIS has been operated under a low-duty factor (10 -2 -10 -3 ), in which the gas flow is not being pulsed. A solenoid-type gas valve, having a simple structure compared to the piezo-electric type, was attached to the outside of the PIGIS chamber in order to control the gas flow into the PIGIS chimney. Beam tests for Ne with gas pulsing showed that the pressure response time should actually be a few tens ms, and the intensity of Ne 6+ was increased by ten times, from 20 to 200 eμA. The gas pulsing also improved the average vacuum in the low energy beam transport (LEBT) line by a factor of 4. When producing H 2 + , H 3 + , and He 1+ by PIGIS with gas pulsing, the beam loss of highly charged ions from electron cyclotron resonance ion sources in the LEBT was reduced to be negligible; meanwhile, it was around 30% without gas pulsing. This paper describes the gas-pulsing technique and the preliminary results, as well as some recent developments in the NIRS-PIGIS

  2. Systematic analysis of neutron yields from thick targets bombarded by heavy ions and protons with moving source model

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Takashi; Kurosawa, Tadahiro; Nakamura, Takashi E-mail: nakamura@cyric.tohoku.ac.jp

    2002-03-21

    A simple phenomenological analysis using the moving source model has been performed on the neutron energy spectra produced by bombarding thick targets with high energy heavy ions which have been systematically measured at the Heavy-Ion Medical Accelerator (HIMAC) facility (located in Chiba, Japan) of the National Institute of Radiological Sciences (NIRS). For the bombardment of both heavy ions and protons in the energy region of 100-500 MeV per nucleon, the moving source model incorporating the knock-on process could be generally successful in reproducing the measured neutron spectra within a factor of two margin of accuracy. This phenomenological analytical equation is expressed having several parameters as functions of atomic number Z{sub p}, mass number A{sub p}, energy per nucleon E{sub p} for projectile, and atomic number Z{sub T}, mass number A{sub T} for target. By inputting these basic data for projectile and target into this equation we can easily estimate the secondary neutron energy spectra at an emission angle of 0-90 deg. for bombardment with heavy ions and protons in the aforementioned energy region. This method will be quite useful to estimate the neutron source term in the neutron shielding design of high energy proton and heavy ion accelerators.

  3. Genetic Variation and Association Analysis of the SSR Markers Linked to the Major Drought-Yield QTLs of Rice.

    Science.gov (United States)

    Tabkhkar, Narjes; Rabiei, Babak; Samizadeh Lahiji, Habibollah; Hosseini Chaleshtori, Maryam

    2018-02-24

    Drought is one of the major abiotic stresses, which hampers the production of rice worldwide. Informative molecular markers are valuable tools for improving the drought tolerance in various varieties of rice. The present study was conducted to evaluate the informative simple sequence repeat (SSR) markers in a diverse set of rice genotypes. The genetic diversity analyses of the 83 studied rice genotypes were performed using 34 SSR markers closely linked to the major quantitative trait loci (QTLs) of grain yield under drought stress (qDTYs). In general, our results indicated high levels of polymorphism. In addition, we screened these rice genotypes at the reproductive stage under both drought stress and nonstressful conditions. The results of the regression analysis demonstrated a significant relationship between 11 SSR marker alleles and the plant paddy weight under stressful conditions. Under the nonstressful conditions, 16 SSR marker alleles showed a significant correlation with the plant paddy weight. Finally, four markers (RM279, RM231, RM166, and RM231) demonstrated a significant association with the plant paddy weight under both stressful and nonstressful conditions. These informative-associated alleles may be useful for improving the crop yield under both drought stress and nonstressful conditions in breeding programs.

  4. On the application of the Onsager theory to the description of the free-ion yield observed in 'warm liquids' irradiated by γ rays

    International Nuclear Information System (INIS)

    Ferrando, A.; Torrente-Lujan, E.; Munoz, R.; Drijard, D.

    1990-01-01

    We have analysed existing data on the free ion yield produced by γ radiolysis of 'warm liquids' namely neopentane, 2,2,4,4-tetramethyl pentane, tetramethyl silane, tetramethyl germanium and tetramethyl tin, within the framework of the Onsager theory. Four distribution functions (describing the separation distance r betweenn electron-ion pairs at thermalization) were considered: a delta function, an exponential function, an exponential times r, and an exponential times r2. With a suitable choice of the two adjustable parameters, G(∞) and ρ where G(∞) is the number of electron-ion pairs initially produced per every 100 eV released in the sample, and ρ is the mean thermalization distance-all four distributions describe the data approximately. However, an independent estimate of G(∞) based on the justifiable assumption that the ratio between the average energy W, which is necessary to create an electron-ion pair, and the ionization energy, is the same in the liquid as it is in the gas, allows a choice to be made between these functions. In all liquids, it is observed that the data fall below the predictions of the Onsager theorty, at fields smaller than 3 kV/cm. We discuss reasons why these discrepancies are to be expected. A least-squares polynomial fit representation of the data (in powers of the applied electric field E) indicates that the usual linear expansion of the free ion yield, G(E)=G(0)(1+E/E 0 ), does not provide a good representation of the data, not even at low fields.(Author)

  5. Analysis of meteorological variations on wheat yield and its estimation using remotely sensed data. A case study of selected districts of Punjab Province, Pakistan (2001-14

    Directory of Open Access Journals (Sweden)

    Rafia Mumtaz

    2017-10-01

    Full Text Available Land management for crop production is an essential human activity that supports life on Earth. The main challenge to be faced by the agriculture sector in coming years is to feed the rapidly growing population while maintaining the key resources such as soil fertility, efficient land use, and water. Climate change is also a critical factor that impacts agricultural production. Among others, a major effect of climate change is the potential alterations in the growth cycle of crops which would likely lead to a decline in the agricultural output. Due to the increasing demand for proper agricultural management, this study explores the effects of meteorological variation on wheat yield in Chakwal and Faisalabad districts of Punjab, Pakistan and used normalised difference vegetation index (NDVI as a predictor for yield estimates. For NDVI data (2001-14, the NDVI product of Moderate Resolution Imaging spectrometer (MODIS 16-day composites data has been used. The crop area mapping has been realised by classifying the satellite data into different land use/land covers using iterative self-organising (ISO data clustering. The land cover for the wheat crop was mapped using a crop calendar. The relation of crop yield with NDVI and the impact of meteorological parameters on wheat growth and its yield has been analysed at various development stages. A strong correlation of rainfall and temperature was found with NDVI data, which determined NDVI as a strong predictor of yield estimation. The wheat yield estimates were obtained by linearly regressing the reported crop yield against the time series of MODIS NDVI profiles. The wheat NDVI profiles have shown a parabolic pattern across the growing season, therefore parabolic least square fit (LSF has been applied prior to linear regression. The coefficients of determination (R2 between the reported and estimated yield was found to be 0.88 and 0.73, respectively, for Chakwal and Faisalabad. This indicates that the

  6. Variation in viscosity and ion conductivity of a polymer–salt complex ...

    Indian Academy of Sciences (India)

    The ion conductivity shows a strong increase for an irradiation of. 35 kGy. DSC studies indicate a decrease in crystallinity with gamma dose. Keywords. Gamma irradiation; polymer electrolyte; viscosity; ion conductivity. PACS Nos 61.82.Pv; 66.30.Dn; 47.57.Ng; 81.70.Pg. 1. Introduction. When polymers are exposed to high ...

  7. Deciphering Natural Allelic Variation in Switchgrass for Biomass Yield and Quality Using a Nested Association Mapping Population

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Malay C. [The Samuel Roberts Noble Foundation, Inc., Ardmore, OK (United States). Forage Improvement Division (FID); Brummer, E. Charles [The Samuel Roberts Noble Foundation, Inc., Ardmore, OK (United States); Kaeppler, Shawn [Univ. of Wisconsin, Madison, WI (United States); Bhandari, Hem S. [Univ. of Tennessee, Knoxville, TN (United States)

    2016-10-28

    Switchgrass (Panicum virgatum L.) is a C4 grass with high biomass yield potential and a model species for bioenergy feedstock development. Understanding the genetic basis of quantitative traits is essential to facilitate genome-enabled breeding programs. The nested association mapping (NAM) analysis combines the best features of both bi-parental and association analyses and can provide high power and high resolution in QTL detection and will ensure significant improvements in biomass yield and quality. To develop a NAM population of switchgrass, 15 highly diverse genotypes with specific characteristics were selected from a diversity panel and crossed to a recurrent parent, AP13, a genotype selected for whole genome sequencing and parent of a mapping population. Ten genotypes from each of the 15 F1 families were then chain crossed. Progenies form each family were randomly selected to develop the NAM population. The switchgrass NAM population consists of a total of 2000 genotypes from 15 families. All the progenies, founder parents, F1 parents (n=2350) were evaluated in replicated field trials at Ardmore, OK and Knoxville, TN. Phenotypic data on plant height, tillering ability, regrowth, flowering time, and biomass yield were collected. Dried biomass samples were also analyzed using prediction equations of NIRS at the Noble Foundation and for lignin content, S/G ratio, and sugar release characteristics at the NREL. Genomic shotgun sequencing of 15 switchgrass NAM founder parental genomes at JGI produced 28-66 Gb high-quality sequence data. Alignment of these sequences with the reference genome, AP13 (v3.0), revealed that up to 99% of the genomic sequences mapped to the reference genome. A total of 2,149 individuals from NAM populations were sequenced by exome capture and two sets of 15 SNP matrices (one for each family) were generated. QTL associated with important traits have been identified and verified in breeding populations. The QTL detected and their associated

  8. Sources of pre-analytical variations in yield of DNA extracted from blood samples: analysis of 50,000 DNA samples in EPIC.

    Directory of Open Access Journals (Sweden)

    Elodie Caboux

    Full Text Available The European Prospective Investigation into Cancer and nutrition (EPIC is a long-term, multi-centric prospective study in Europe investigating the relationships between cancer and nutrition. This study has served as a basis for a number of Genome-Wide Association Studies (GWAS and other types of genetic analyses. Over a period of 5 years, 52,256 EPIC DNA samples have been extracted using an automated DNA extraction platform. Here we have evaluated the pre-analytical factors affecting DNA yield, including anthropometric, epidemiological and technical factors such as center of subject recruitment, age, gender, body-mass index, disease case or control status, tobacco consumption, number of aliquots of buffy coat used for DNA extraction, extraction machine or procedure, DNA quantification method, degree of haemolysis and variations in the timing of sample processing. We show that the largest significant variations in DNA yield were observed with degree of haemolysis and with center of subject recruitment. Age, gender, body-mass index, cancer case or control status and tobacco consumption also significantly impacted DNA yield. Feedback from laboratories which have analyzed DNA with different SNP genotyping technologies demonstrate that the vast majority of samples (approximately 88% performed adequately in different types of assays. To our knowledge this study is the largest to date to evaluate the sources of pre-analytical variations in DNA extracted from peripheral leucocytes. The results provide a strong evidence-based rationale for standardized recommendations on blood collection and processing protocols for large-scale genetic studies.

  9. Investigation of the hydrogen multilayered target H/T-D{sub 2} and muonic X-ray yields in ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Gheisari, R., E-mail: gheisari@pgu.ac.ir [Physics Department, Persian Gulf University, Bushehr 75169 (Iran, Islamic Republic of)

    2011-12-21

    This paper extends applications of the multilayered solid target H/T-D{sub 2}, which is kept at 3 K. The time evolutions of muonic tritium atoms ({mu}t) are obtained, by taking into account {mu}t production rate at different places of deuterium material. The apparatus H/T-D{sub 2} can be used for checking nuclear properties of implanted ions, which take part at muon transfer. Electromagnetic X-rays are generated by muon atomic transitions. The muonic X-ray transition energies are strongly affected by the size of nuclei. Here, a solid hydrogen-tritium (H/T) with a Almost-Equal-To 1 mm thick is used for {mu}t production. For ion implantation, the required amount of deuterium material is determined to be about 3.2 {mu}m. Moreover, the muonic X-ray yields are estimated and compared with those of the arrangement H/T-D{sub 2}. While the present target requires argon ion beam intensity nearly a factor of 2 times smaller; gives a relatively higher X-ray yield (15% enhancement per hour) at the energy 644 keV with the detection efficiency of Almost-Equal-To 1%.

  10. Temporal and Spatial Variation of Water Yield Modulus in the Yangtze River Basin in Recent 60 Years

    Science.gov (United States)

    Shi, Xiaoqing; Weng, Baisha; Qin, Tianling

    2018-01-01

    The Yangtze River Basin is the largest river basin of Asia and the third largest river basin of the world, the gross water resources amount ranks first in the river basins of the country, and it occupies an important position in the national water resources strategic layout. Under the influence of climate change and human activities, the water cycle has changed. The temporal and spatial distribution of precipitation in the basin is more uneven and the floods are frequent. In order to explore the water yield condition in the Yangtze River Basin, we selected the Water Yield Modulus (WYM) as the evaluation index, then analyzed the temporal and spatial evolution characteristics of the WYM in the Yangtze River Basin by using the climate tendency method and the M-K trend test method. The results showed that the average WYM of the Yangtze River Basin in 1956-2015 are between 103,600 and 1,262,900 m3/km2, with an average value of 562,300 m3/km2, which is greater than the national average value of 295,000 m3/km2. The minimum value appeared in the northwestern part of the Tongtian River district, the maximum value appeared in the northeastern of Dongting Lake district. The rate of change in 1956-2015 is between -0.68/a and 0.79/a, it showed a downward trend in the western part but not significantly, an upward trend in the eastern part reached a significance level of α=0.01. The minimum value appeared in the Tongtian River district, the largest value appeared in the Hangjia Lake district, and the average tendency rate is 0.04/a in the whole basin.

  11. Energy variational analysis of ions in water and channels: Field theory for primitive models of complex ionic fluids

    International Nuclear Information System (INIS)

    Eisenberg, Bob; Hyon, YunKyong; Liu, Chun

    2010-01-01

    Ionic solutions are mixtures of interacting anions and cations. They hardly resemble dilute gases of uncharged noninteracting point particles described in elementary textbooks. Biological and electrochemical solutions have many components that interact strongly as they flow in concentrated environments near electrodes, ion channels, or active sites of enzymes. Interactions in concentrated environments help determine the characteristic properties of electrodes, enzymes, and ion channels. Flows are driven by a combination of electrical and chemical potentials that depend on the charges, concentrations, and sizes of all ions, not just the same type of ion. We use a variational method EnVarA (energy variational analysis) that combines Hamilton’s least action and Rayleigh’s dissipation principles to create a variational field theory that includes flow, friction, and complex structure with physical boundary conditions. EnVarA optimizes both the action integral functional of classical mechanics and the dissipation functional. These functionals can include entropy and dissipation as well as potential energy. The stationary point of the action is determined with respect to the trajectory of particles. The stationary point of the dissipation is determined with respect to rate functions (such as velocity). Both variations are written in one Eulerian (laboratory) framework. In variational analysis, an “extra layer” of mathematics is used to derive partial differential equations. Energies and dissipations of different components are combined in EnVarA and Euler–Lagrange equations are then derived. These partial differential equations are the unique consequence of the contributions of individual components. The form and parameters of the partial differential equations are determined by algebra without additional physical content or assumptions. The partial differential equations of mixtures automatically combine physical properties of individual (unmixed) components

  12. Energy variational analysis of ions in water and channels: Field theory for primitive models of complex ionic fluids.

    Science.gov (United States)

    Eisenberg, Bob; Hyon, Yunkyong; Liu, Chun

    2010-09-14

    Ionic solutions are mixtures of interacting anions and cations. They hardly resemble dilute gases of uncharged noninteracting point particles described in elementary textbooks. Biological and electrochemical solutions have many components that interact strongly as they flow in concentrated environments near electrodes, ion channels, or active sites of enzymes. Interactions in concentrated environments help determine the characteristic properties of electrodes, enzymes, and ion channels. Flows are driven by a combination of electrical and chemical potentials that depend on the charges, concentrations, and sizes of all ions, not just the same type of ion. We use a variational method EnVarA (energy variational analysis) that combines Hamilton's least action and Rayleigh's dissipation principles to create a variational field theory that includes flow, friction, and complex structure with physical boundary conditions. EnVarA optimizes both the action integral functional of classical mechanics and the dissipation functional. These functionals can include entropy and dissipation as well as potential energy. The stationary point of the action is determined with respect to the trajectory of particles. The stationary point of the dissipation is determined with respect to rate functions (such as velocity). Both variations are written in one Eulerian (laboratory) framework. In variational analysis, an "extra layer" of mathematics is used to derive partial differential equations. Energies and dissipations of different components are combined in EnVarA and Euler-Lagrange equations are then derived. These partial differential equations are the unique consequence of the contributions of individual components. The form and parameters of the partial differential equations are determined by algebra without additional physical content or assumptions. The partial differential equations of mixtures automatically combine physical properties of individual (unmixed) components. If a new

  13. Energy variational analysis of ions in water and channels: Field theory for primitive models of complex ionic fluids

    Science.gov (United States)

    Eisenberg, Bob; Hyon, YunKyong; Liu, Chun

    2010-09-01

    Ionic solutions are mixtures of interacting anions and cations. They hardly resemble dilute gases of uncharged noninteracting point particles described in elementary textbooks. Biological and electrochemical solutions have many components that interact strongly as they flow in concentrated environments near electrodes, ion channels, or active sites of enzymes. Interactions in concentrated environments help determine the characteristic properties of electrodes, enzymes, and ion channels. Flows are driven by a combination of electrical and chemical potentials that depend on the charges, concentrations, and sizes of all ions, not just the same type of ion. We use a variational method EnVarA (energy variational analysis) that combines Hamilton's least action and Rayleigh's dissipation principles to create a variational field theory that includes flow, friction, and complex structure with physical boundary conditions. EnVarA optimizes both the action integral functional of classical mechanics and the dissipation functional. These functionals can include entropy and dissipation as well as potential energy. The stationary point of the action is determined with respect to the trajectory of particles. The stationary point of the dissipation is determined with respect to rate functions (such as velocity). Both variations are written in one Eulerian (laboratory) framework. In variational analysis, an "extra layer" of mathematics is used to derive partial differential equations. Energies and dissipations of different components are combined in EnVarA and Euler-Lagrange equations are then derived. These partial differential equations are the unique consequence of the contributions of individual components. The form and parameters of the partial differential equations are determined by algebra without additional physical content or assumptions. The partial differential equations of mixtures automatically combine physical properties of individual (unmixed) components. If a new

  14. Variation in seed mineral elements profile and yield in field bean (Vicia faba L. var. minor genotypes

    Directory of Open Access Journals (Sweden)

    Sara Lombardo

    2016-12-01

    Full Text Available Field bean (Vicia faba L. var. minor is one of the major leguminous crops cultivated in the world and mainly destined for animal feed. Although its seed is generally recognised as a good protein source, little is known about its mineral elements profile, which is an important aspect for a balanced animal diet. Therefore, the aim of the present work was to assess the seed mineral elements composition, along with some key production parameters, in eight field bean genotypes grown in a Mediterranean environment, without intensive management, over two years (2009/10 and 2010/11. Independently of the year, the seed of Chiaro di Torre Lama was the richest in phosphorus (P, magnesium, calcium and iron contents, while that of Sint 6 and Motta Chiaro 69 were the most effective accumulators of potassium and zinc, respectively. While all the genotypes yielded better in the second year (with more rainfall, the seasonal effect on seed mineral elements composition depended on the genotype. Indeed, the P content was 46% lower in Chiaro di Torre Lama, Motta Chiaro 69 and Sint 6 in the second year, while there was only a negligible seasonal effect for Sint 8 with respect to Fe content. Overall, this crop is reasonably productive under a low management regime and its seed can supply significant amounts of certain minerals (particularly P in feed formulations. Both aspects are important in a perspective of optimising field bean production in the Mediterranean area and, hence, improving farmers’ income.

  15. Comparison of specular H-atomic-beam intensity and C+ secondary-ion yield at thermally activated decrease of a carbon layer on a Ni(110) surface

    International Nuclear Information System (INIS)

    Kaarmann, H.; Hoinkes, H.; Wilsch, H.

    1983-01-01

    The thermally activated disappearance of a carbon layer on a Ni(110) surface was investigated by the scattering of atomic hydrogen and by secondary-ion mass spectrometry. Decreasing C coverage at surface temperatures kept constant in each case at values between 650 and 750 K resulted in an exponential decrease of specular H-beam intensity as well as C + secondary-ion yield. This decrease in both cases fits first-order kinetics (presumable diffusion into the bulk) with an identical rate constant as a function of surface temperature and results finally in a preexponential frequency ν = 10/sup() 10plus-or-minus1/ s -1 and an activation energy E/sub A/ = 1.8 +- 0.2 eV

  16. Formation mechanism and yield of molecules ejected from ZnS, CdS, and FeS2 during ion bombardment

    International Nuclear Information System (INIS)

    Nikzad, S.; Calaway, W.F.; Pellin, M.J.; Young, C.E.; Gruen, D.M.; Tombrello, T.A.

    1994-01-01

    Neutral species ejected from single crystals of ZnS, CdS, and FeS 2 during ion bombardment by 3 keV Ar + were detected by laser post-ionization followed by time-of-flight mass spectrometry. While metal atoms (Fe, Zn, Cd) and S 2 were the dominant species observed, substantial amounts of S, FeS, Zn 2 , ZnS, Cd 2 , and CdS were also detected. The experimental results demonstrate that molecules represent a larger fraction of the sputtered yield than was previously believed from secondary ion mass spectrometry experiments. In addition, the data suggest that the molecules are not necessarily formed from adjacent atoms in the solid and that a modified form of the recombination model could provide a mechanism for their formation

  17. Variations of Low-energy Ion Distributions Measured in the Heliosheath

    International Nuclear Information System (INIS)

    Decker, R. B.; Roelof, E. C.; Hill, M. E.; Krimigis, S. M.

    2010-01-01

    This report is an update of low-energy ion intensities and angular distributions measured recently by the Low Energy Charged Particle instruments on the Voyager 1 and 2 spacecraft in the inner heliosheath.

  18. On the application of the Onsager theory to the description of the free-ion yield observed in warn liquids irradiated by {gamma}-rays

    Energy Technology Data Exchange (ETDEWEB)

    Munoz, R. C.; Drijard, D.; Ferrando, A.; Torrente-Lujan, E.

    1990-07-01

    We have analysed existing data on the free ion yield produced by {gamma}-radiolysis of warm liquids, namely neopentane, 2,2,4,4-tetramethyl pentane, tetramethyl silane, tetramethyl germanium and tetramethyl tin, within the framework of the Onsager theory. An independent estimate of G({infinity}) allows a choice to be made between the four distribution functions considered in this work. Moreover, a polynomial fit to the data in powers of the applied electric field E) indicates that the usual linear expansion, G(E) = G(0)(l + E/E0), does not provide a good representation of the data, not even at low field. (Author) 24 refs.

  19. On the application of the Onsager theory to the description of the free-ion yield observed in 'warn liquids' irradiated by γ-rays

    International Nuclear Information System (INIS)

    Munoz, R. C.; Drijard, D.; Ferrando, A.; Torrente-Lujan, E.

    1990-01-01

    We have analysed existing data on the free ion yield produced by γ-radiolysis of warm liquids, namely neopentane, 2,2,4,4-tetramethyl pentane, tetramethyl silane, tetramethyl germanium and tetramethyl tin, within the framework of the Onsager theory. An independent estimate of G(∞) allows a choice to be made between the four distribution functions considered in this work. Moreover, a polynomial fit to the data in powers of the applied electric field E) indicates that the usual linear expansion, G(E) = G(0)(l + E/E0), does not provide a good representation of the data, not even at low field. (Author) 24 refs

  20. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    Science.gov (United States)

    Mahadtanapuk, S.; Teraarusiri, W.; Phanchaisri, B.; Yu, L. D.; Anuntalabhochai, S.

    2013-07-01

    Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60-80 keV to a beam fluence range of 2 × 1016-2 × 1017 ions/cm2. The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 106 spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11).

  1. Measurements of isomeric yield ratios of fission products from proton-induced fission on natU and 232Th via direct ion counting

    Directory of Open Access Journals (Sweden)

    Rakopoulos Vasileios

    2017-01-01

    Full Text Available Independent isomeric yield ratios (IYR of 81Ge, 96Y, 97Y, 97Nb, 128Sn and 130Sn have been determined in the 25 MeV proton-induced fission of natU and 232Th. The measurements were performed at the Ion Guide Isotope Separator On-Line (IGISOL facility at the University of Jyväskylä. A direct ion counting measurement of the isomeric fission yield ratios was accomplished for the first time, registering the fission products in less than a second after their production. In addition, the IYRs of natU were measured by means of γ-spectroscopy in order to verify the consistency of the recently upgraded experimental setup. From the obtained results, indications of a dependence of the production rate on the fissioning system can be noticed. These data were compared with data available in the literature, whenever possible. Using the TALYS code and the experimentally obtained IYRs, we also deduced the average angular momentum of the fission fragments after scission.

  2. Charged particle yields and spectra in p+p and Heavy Ion Collisions with ATLAS at the LHC

    CERN Document Server

    Dolejší, J; The ATLAS collaboration

    2010-01-01

    The ATLAS experiment has extensive charged particle tracking over full azimuth and within |eta|<2.5. The spectrometer consists of three pixel layers and four double-layer strip layers, giving 11 space points in all. The existing tracking software used for proton-proton collisions has been optimized for the high-multiplicity heavy ion environment. Extensions of the existing tracking to lower pT (100 MeV) using tracks and pixel tracklets, work underway for p+p, will be discussed in the context of heavy ion collisions. Finally, by correlating high momentum tracks with the ATLAS calorimetry, fake tracks can also be rejected at very high pT. The physics performance of the ATLAS inner detector for dN/deta, inclusive particle spectra, and two-particle correlations (in delta-eta and delta-phi) will be discussed. The tracking performance within jets, which is essential for the measurement of jet fragmentation functions, will also be presented.

  3. Study on character variation induced by introducing exogenous DNA into upland cotton with ion implantation

    International Nuclear Information System (INIS)

    Cheng Beijiu; Tian Qiuyuan; Li Zhan; Zhou Liren

    1996-01-01

    The exogenous DNAs of G. Bickll P. and H. Cannabinus were introduced into the upland cotton Si 2 by Ar + implantation and DNA solution trickling method. The results showed that the exogenous DNA introduction was promoted significantly and the types and frequencies of character variation in progeny were increased by Ar + implantation. Furthermore, most of the variation tend to be stable. Among the Ar + implantation doses tested, 2 x 10 15 Ar + /cm 2 was the best for introducing exogenous DNA and inducing character variation, the variation rate reached to 16.2%. Some new lines with character of resistance to wilt disease, early maturity, few gland in seed and fine fiber quality have been obtained

  4. Yields of the rare-earth neutron-deficient isotopes in the reactions of Mo isotopes with 40Ca ions

    International Nuclear Information System (INIS)

    Adam, J.; Chaloun, P.; Gangrskij, Yu.P.

    1999-01-01

    The results of the joint Russian-Chinese experiment on the measurements of the reaction cross sections of the rare-earth neutron-deficient isotopes production and the study of their decay scheme are presented. The studied nuclides were obtained in the reactions 92 Mo + 40 Ca and 97 Mo + 40 Ca on the 4-meter cyclotron of the Flerov Laboratory of Nuclear Reactions, JINR. The recoil nuclei were stopped in the inert gas and transported by the gas flow to the detectors. The single and coincidence spectra of γ-, x-rays and delayed protons were measured. The enhanced yield of the reactions with the charge particle evaporation was observed

  5. Spatial variations in the suprathermal ion distributions during substorms in the plasma sheet

    International Nuclear Information System (INIS)

    Kistler, L.M.; Moebius, E.; Klecker, B.; Gloeckler, G.; Ipavich, F.M.; Hamilton, D.C.

    1990-01-01

    Using data from AMPTE IRM and AMPTE CCE, the authors have determined the pre- and post-injection suprathermal energy spectra for the ion species H + , O + , He + , and He ++ for six events in which substorm-associated particle injections are observed in both the near-Earth plasma sheet and farther down the tail. They find similar spectral changes in both locations, with the spectra becoming harder with the injection. Post-injection, the flux decreases exponentially with radial distance. Approximately the same gradient is observed in all species. In addition, they find that although the O + /H + and the He ++ /H + ratios increase with energy per charge, the ratios are approximately the same at the same energy per charge at the two spacecraft. The observations are difficult to explain either with a model in which the ions are accelerated at a neutral line and transported toward Earth or with a model in which the ions are accelerated in the near-Earth region by current disruption/diversion and transported down the tail. In either case, the ions would have to be transported throughout the tail without much energization or deenergization in order to explain the energy per charge correlations. Further, earthward transport without energization would not lead to the observed radial gradient. A combination of these acceleration mechanisms, a disturbance that propagates throughout the plasma sheet, or a more global mechanism may explain the observations

  6. New aspects in plasmaspheric ion temperature variations from INTERBALL 2 and MAGION 5 measurements

    Czech Academy of Sciences Publication Activity Database

    Kotova, G.; Bezrukikh, V.; Verigin, M.; Šmilauer, Jan

    2008-01-01

    Roč. 70, 2-4 (2008), s. 399-406 ISSN 1364-6826 Institutional research plan: CEZ:AV0Z30420517 Keywords : Plasmasphere * Ion temperature * Electron temperature * Magnetic storm Subject RIV: JV - Space Technology Impact factor: 1.667, year: 2008

  7. Study on yeast mutant with high alcohol yield fermented in sweet sorghum juice using carbon ion irradiation

    International Nuclear Information System (INIS)

    Yan Yaping; Lu Dong; Wang Jufang; Dong Xicun; Gao Feng; Ma Liang; Li Wenjian

    2009-01-01

    Five mutants with high ability of producing alcohol were selected out by using TTC as an indicator after irradiation of the alcohol yeast with 100 MeV/u carbon ions. The fermentation experiment in sweet sorghum juice showed that the alcohol production ability of mutant T4 strain increased 18.6% compared to the control strain. The residual sugar content in the juice was decreased too. After that,the optimum fermentation conditions of the T4 strain in sweet sorghum juice were investigated. The results showed that the optimum temperature and pH value for fermentation were 30 degree C and 4.5, respectively. The verification experiment was fermented in a 10 l bio-reactor and the obtained data indicated that the fermentative rate and the ability of producing alcohol in T4 strain was higher than that in the control strain under the same fermentation condition. (authors)

  8. Effect of the moment-of-inertia variation on Coulomb-nuclear interference in heavy ion scattering

    International Nuclear Information System (INIS)

    Bolotin, Yu.L.; Gonchar, V.Yu.; Inopin, E.V.; Chekanov, N.A.

    1987-01-01

    Effect of moment-of-inertia (MI) variation on probabilities of the Coulomb excitation of nucleus rotational states (RS) is investigated. The calculation is performed in the generalized quasiclassical approximation. Cillisions with an aimed parameter equal to 0 and recording of scattered ion at angles close to 180 deg were considered. Effect of MI dependence on angular momentum (AM) on the RS Coulomb excitation probability in the 86 Kr+ 238 U process at 400 MeV 86 Kr has been studied. For small AMs (I < 10), when the MI variation can be neglected, the Coulomb-nuclear interference leads to a marked shift of RS excitation probability maxima. However, with increasing transferred AM the convergence of probabilities conditioned with mutual compensation of phases shift related to the MI variation and Coulomb-nucleus interference, is noted. It is also noted that correct parameters of deformed nuclei extracted from experiments on the Coulomb excitation of high-spin states can be obtained only during simultaneous accountancy of both the Coulomb-nuclear interference and the MI variation of excited nuclei

  9. The Zodiacal Cloud Model applied to the Martian atmosphere. Diurnal variations in meteoric ion layers

    Science.gov (United States)

    Carrillo-Sánchez, J. D.; Plane, J. M. C.; Withers, P.; Fallows, K.; Nesvorny, D.; Pokorný, P.

    2016-12-01

    Sporadic metal layers have been detected in the Martian atmosphere by radio occultation measurements using the Mars Express Orbiter and Mars Global Surveyor spacecraft. More recently, metallic ion layers produced by the meteor storm event following the close encounter between Comet Siding Spring (C/2013 A1) and Mars were identified by the Imaging UltraViolet Spectrograph (IUVS) and the Neutral Gas and Ion Mass Spectrometer (NGIMS) on the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft. Work is now in progress to detect the background metal layers produced by the influx of sporadic meteors. In this study we predict the likely appearance of these layers. The Zodiacal Dust Cloud (ZDC) model for particle populations released by asteroids (AST), and dust grains from Jupiter Family Comets (JFCs) and Halley-Type Comets (HTCs) has been combined with a Monte Carlo sampling method and the Chemical ABlation MODel (CABMOD) to predict the ablation rates of Na, K, Fe, Si, Mg, Ca and Al above 40 km altitude in the Martian atmosphere. CABMOD considers the standard treatment of meteor physics, including the balance of frictional heating by radiative losses and the absorption of heat energy through temperature increases, melting phase transitions and vaporization, as well as sputtering by inelastic collisions with the air molecules. The vertical injection profiles are input into the Leeds 1-D Mars atmospheric model which includes photo-ionization, and gas-phase ion-molecule and neutral chemistry, in order to explore the evolution of the resulting metallic ions and atoms. We conclude that the dominant contributor in the Martian's atmosphere is the JFCs over other sources. Finally, we explore the changes of the neutral and ionized Na, Mg and Fe layers over a diurnal cycle.

  10. Towards better description of solar activity variation in the International Reference Ionosphere topside ion composition model

    Czech Academy of Sciences Publication Activity Database

    Truhlík, Vladimír; Bilitza, D.; Třísková, Ludmila

    2015-01-01

    Roč. 55, č. 8 (2015), s. 2099-2105 ISSN 0273-1177 R&D Projects: GA MŠk(CZ) LH11123 Institutional support: RVO:68378289 Keywords : ion composition * topside ionosphere * solar activity * empirical model * International Reference Ionosphere Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.409, year: 2015 http://www.sciencedirect.com/science/article/pii/S027311771400489X

  11. A series of inorganic solid nitrogen sources for the synthesis of metal nitride clusterfullerenes: the dependence of production yield on the oxidation state of nitrogen and counter ion.

    Science.gov (United States)

    Liu, Fupin; Guan, Jian; Wei, Tao; Wang, Song; Jiao, Mingzhi; Yang, Shangfeng

    2013-04-01

    A series of nitrogen-containing inorganic solid compounds with variable oxidation states of nitrogen and counter ions have been successfully applied as new inorganic solid nitrogen sources toward the synthesis of Sc-based metal nitride clusterfullerenes (Sc-NCFs), including ammonium salts [(NH4)xH(3-x)PO4 (x = 0-2), (NH4)2SO4, (NH4)2CO3, NH4X (X = F, Cl), NH4SCN], thiocyanate (KSCN), nitrates (Cu(NO3)2, NaNO3), and nitrite (NaNO2). Among them, ammonium phosphates ((NH4)xH(3-x)PO4, x = 1-3) and ammonium thiocyanate (NH4SCN) are revealed to behave as better nitrogen sources than others, and the highest yield of Sc-NCFs is achieved when NH4SCN was used as a nitrogen source. The optimum molar ratio of Sc2O3:(NH4)3PO4·3H2O:C and Sc2O3:NH4SCN:C has been determined to be 1:2:15 and 1:3:15, respectively. The thermal decomposition products of these 12 inorganic compounds have been discussed in order to understand their different performances toward the synthesis of Sc-NCFs, and accordingly the dependence of the production yield of Sc-NCFs on the oxidation state of nitrogen and counter ion is interpreted. The yield of Sc3N@C80 (I(h) + D(5h)) per gram Sc2O3 by using the N2-based group of nitrogen sources (thiocyanate, nitrates, and nitrite) is overall much lower than those by using gaseous N2 and NH4SCN, indicating the strong dependence of the yield of Sc-NCFs on the oxidation state of nitrogen, which is attributed to the "in-situ" redox reaction taking place for the N2-based group of nitrogen sources during discharging. For NH3-based group of nitrogen sources (ammonium salts) which exhibits a (-3) oxidation states of nitrogen, their performance as nitrogen sources is found to be sensitively dependent on the anion, and this is understood by considering their difference on the thermal stability and/or decomposition rate. Contrarily, for the N2-based group of nitrogen sources, the formation of Sc-NCFs is independent to both the oxidation state of nitrogen (+3 or +5) and the

  12. Variations in yield and gluten proteins in durum wheat varieties under late-season foliar versus soil application of nitrogen fertilizer in a northern Mediterranean environment.

    Science.gov (United States)

    Visioli, Giovanna; Bonas, Urbana; Dal Cortivo, Cristian; Pasini, Gabriella; Marmiroli, Nelson; Mosca, Giuliano; Vamerali, Teofilo

    2018-04-01

    With the increasing demand for high-quality foodstuffs and concern for environmental sustainability, late-season nitrogen (N) foliar fertilization of common wheat is now an important and widespread practice. This study investigated the effects of late-season foliar versus soil N fertilization on yield and protein content of four varieties of durum wheat, Aureo, Ariosto, Biensur and Liberdur, in a three-year field trial in northern Italy. Variations in low-molecular-weight glutenins (LMW-GS), high-molecular-weight glutenins (HMW-GS) and gliadins were assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). It was found that N applied to the canopy did not improve protein rate compared with N application to the soil (general mean 138 mg g -1 ), but moderately increased productivity in the high-yielding varieties Liberdur and Biensur (three-year means 7.23 vs 7.13 and 7.53 vs 7.09 t ha -1 respectively). Technological quality was mainly related to variety choice, Aureo and Ariosto having higher protein rates and glutenin/gliadin ratios. Also found was a strong 'variety × N application method' interaction in the proportions of protein subunits within each class, particularly LMW-GS and gliadins. A promising result was the higher N uptake efficiency, although as apparent balance, combined with higher HMW/LMW-GS ratio in var. Biensur. Late-season foliar N fertilization allows N fertilizer saving, potentially providing environmental benefits in the rainy climate of the northern Mediterranean area, and also leads to variety-dependent up-regulation of essential LMW-GS and gliadins. Variety choice is a key factor in obtaining high technological quality, although it is currently associated with modest grain yield. This study provides evidence of high quality in the specific high-yielding variety Biensur, suggesting its potential as a mono-varietal semolina for pasta production. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  13. Near-surface density profiling of Fe ion irradiated Si (100) using extremely asymmetric x-ray diffraction by variation of the wavelength

    Energy Technology Data Exchange (ETDEWEB)

    Khanbabaee, B., E-mail: khanbabaee@physik.uni-siegen.de; Pietsch, U. [Solid State Physics, University of Siegen, D-57068 Siegen (Germany); Facsko, S. [Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden (Germany); Doyle, S. [Synchrotron Light Source ANKA, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany)

    2014-10-20

    In this work, we report on correlations between surface density variations and ion parameters during ion beam-induced surface patterning process. The near-surface density variations of irradiated Si(100) surfaces were investigated after off-normal irradiation with 5 keV Fe ions at different fluences. In order to reduce the x-ray probing depth to a thickness below 5 nm, the extremely asymmetrical x-ray diffraction by variation of wavelength was applied, exploiting x-ray refraction at the air-sample interface. Depth profiling was achieved by measuring x-ray rocking curves as function of varying wavelengths providing incidence angles down to 0°. The density variation was extracted from the deviations from kinematical Bragg angle at grazing incidence angles due to refraction of the x-ray beam at the air-sample interface. The simulations based on the dynamical theory of x-ray diffraction revealed that while a net near-surface density decreases with increasing ion fluence which is accompanied by surface patterning, there is a certain threshold of ion fluence to surface density modulation. Our finding suggests that the surface density variation can be relevant with the mechanism of pattern formation.

  14. Composition variations of low energy heavy ions during large solar energetic particle events

    Energy Technology Data Exchange (ETDEWEB)

    Ho, George C., E-mail: George.Ho@jhuapl.edu; Mason, Glenn M., E-mail: Glenn.Mason@jhuapl.edu [Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723 (United States)

    2016-03-25

    The time-intensity profile of large solar energetic particle (SEP) event is well organized by solar longitude as observed at Earth orbit. This is mostly due to different magnetic connection to the shock that is associated with large SEP event propagates from the Sun to the heliosphere. Earlier studies have shown event averaged heavy ion abundance ratios can also vary as a function of solar longitude. It was found that the Fe/O ratio for high energy particle (>10 MeV/nucleon) is higher for those western magnetically well connected events compare to the eastern events as observed at L1 by the Advanced Composition Explorer (ACE) spacecraft. In this paper, we examined the low energy (∼1 MeV/nucleon) heavy ions in 110 isolated SEP events from 2009 to the end of 2014. In addition, the optical and radio signatures for all of our events are identified and when data are available we also located the associated coronal mass ejection (CME) data. Our survey shows a higher Fe/O ratio at events in the well-connected region, while there are no corrections between the event averaged elemental composition with the associated coronal mass ejection speed. This is inconsistent with the higher energy results, but inline with other recent low-energy measurements.

  15. Evolution of heavy ions (He{sup 2+}, H{sup +}) radiolytic yield of molecular hydrogen vs. ''Track-Segment'' LET values

    Energy Technology Data Exchange (ETDEWEB)

    Crumiere, Francis; Vandenborre, Johan; Blain, Guillaume; Fattahi, Massoud [Nantes Univ., CNRS/IN2P3 (France). SUBATECH Unite Mixte de Recherche 6457; Haddad, Ferid [Nantes Univ., CNRS/IN2P3 (France). SUBATECH Unite Mixte de Recherche 6457; Cyclotron Arronax, Saint Herblain (France)

    2017-08-01

    Ionizing radiation's effects onto water molecules lead to the ionization and/or the excitation of them. Then, these phenomena are followed by the formation of radicals and molecular products. The linear energy transfer (LET), which defines the energy deposition density along the radiation length, is different according to the nature of ionizing particles. Thus, the values of radiolytic yields, defined as the number of radical and molecular products formed or consumed by unit of deposited energy, evolve according to this parameter. This work consists in following the evolution of radiolytic yield of molecular hydrogen and ferric ions according to the ''Track-Segment'' LET of ionizing particles (protons, helions). Concerning G(Fe{sup 3+}) values, it seems that the energy deposited into the Bragg peak does not play the main role for the Fe{sup 3+} radiolytic formation, whereas for the G(H{sub 2}) it is the case with a component around 40% of the Bragg peak in the dihydrogen production. Therefore, as main results of this work, for high energetic Helion and Proton beams, the G(Fe{sup 3+}) values, which can be used for further dosimetry studies for example during the α radiolysis experiments, and the primary g(H{sub 2}) values for the Track-Segment LET, which can be used to determine the dihydrogen production by α-emitters, are published.

  16. Equilibria model for pH variations and ion adsorption in capacitive deionization electrodes.

    Science.gov (United States)

    Hemmatifar, Ali; Oyarzun, Diego I; Palko, James W; Hawks, Steven A; Stadermann, Michael; Santiago, Juan G

    2017-10-01

    Ion adsorption and equilibrium between electrolyte and microstructure of porous electrodes are at the heart of capacitive deionization (CDI) research. Surface functional groups are among the factors which fundamentally affect adsorption characteristics of the material and hence CDI system performance in general. Current CDI-based models for surface charge are mainly based on a fixed (constant) charge density, and do not treat acid-base equilibria of electrode microstructure including so-called micropores. We here expand current models by coupling the modified Donnan (mD) model with weak electrolyte acid-base equilibria theory. In our model, surface charge density can vary based on equilibrium constants (pK's) of individual surface groups as well as micropore and electrolyte pH environments. In this initial paper, we consider this equilibrium in the absence of Faradaic reactions. The model shows the preferential adsorption of cations versus anions to surfaces with respectively acidic or basic surface functional groups. We introduce a new parameter we term "chemical charge efficiency" to quantify efficiency of salt removal due to surface functional groups. We validate our model using well controlled titration experiments for an activated carbon cloth (ACC), and quantify initial and final pH of solution after adding the ACC sample. We also leverage inductively coupled plasma mass spectrometry (ICP-MS) and ion chromatography (IC) to quantify the final background concentrations of individual ionic species. Our results show a very good agreement between experiments and model. The model is extendable to a wide variety of porous electrode systems and CDI systems with applied potential. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Fabrication and variation of the cut-out yield of beef carcasses in Venezuela: anatomical description of the process and equivalency of cut nomenclature to North American counterparts

    Directory of Open Access Journals (Sweden)

    Angela Montero

    2014-06-01

    Full Text Available The typical processes of beef carcass fabrication in Venezuela are anatomically described and the equivalence in cut nomenclature with that of México and United States is provided. Additionally, 910 carcasses were fabricated to assess yield (kg and percentages of carcass weight in products (subprimals, subprimal groups of distinct commercial value (High, Medium, Low and by-products (bone, fat trimmings using mean values ± standard deviation (DE, coefficient of variation (CV and range of values. Once the carcass is ribbed at the 5th intercostal space, subprimals are obtained by deboning and dissecting the muscle masses (saw cutting is seldom used. In terms of yield, the top three (out of 18 individual subprimals were: Solomo Abierto (boneless Chuck Roll, 39.1± 10.88kg; 14.3± 2.84%, Costilla (bone-in Plate, 22kg± 4.15; 8.12± 0.88% and Solomo de Cuerito (boneless Rib and Loin, 21.6± 3.10kg; 8.0± 0.59%. Cutability values for High-Valued and Medium-Valued subprimal groups were 81.5± 10.3kg (30.2± 1.43% and 67.3± 14.57kg (24.8± 3.22%, respectively; the latter showing the highest CV (13.0%. Fat trimmings were the most variable by-product (10.1± 2.84%, CV = 28.0%. This report serves as a reference for future studies and could facilitate the commercial language for trading beef cuts between the countries involved

  18. Variations in Calcium and Alginate Ions Concentration in Relation to the Properties of Calcium Alginate Nanoparticles

    Directory of Open Access Journals (Sweden)

    Hamed Daemi

    2013-05-01

    Full Text Available Alginate belongs to a group of natural polymers called polysaccharides. They have carboxylic functional groups beside hydroxyls which are common in all polysaccharides. These materials show interesting properties due to theirfunctional groups. One of these properties is the ability of this polymer as a suitable carrier of protecting and transferring drugs and biomolecules. The particle sizes of these polymers are very important for their applications, so different techniques were used for preparation of these materials. In this way polymeric nanoparticles of calcium alginate which are excellent carriers in drug delivery systems were prepared by addition of calcium chloride solution to dilute solution of sodium alginate. Investigation of the size and distribution of nanoparticles were analyzed by SEM method. The concentration effects of both alginate and calcium ions on the size and distribution of  nanoparticles were studied in this research. Results showed that the size of nanoparticles obviously decreased with decreasing polymeric alginate concentration because of lower active sites in polymer chain. On the other hand, thesize and distribution of nanoparticles are significantly improved with increase of calcium cation concentrations. The mean particle size 40-70 nm and spherical shape are the main characteristics of the prepared nanoparticles.

  19. Measurement of the Cupric Ion Concentration Variation near Electrodes in the Copper Electroplating System

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Je Young; Chung, Bum Jin [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The heat fluxes to the side wall imposed at the upper metallic layer, are known to increase with the reduction of layer height. This 'Focusing effect' is varied by cooling condition of upper boundary and height of the metallic layer. The heat transfer experiments were replaced by mass transfer experiments based on the heat and mass transfer analogy concept. When the electroplating system is adopted as the mass transfer system, in order to simulate the different temperature conditions of top and side walls, an electrical resistance was attached to the top wall so that it is mimics hotter wall condition. Because the quantitative temperature conditions according to the electrical resistance were unknown, the methodology development is necessary. The electrical resistance was adopted to the top plate. But the quantitative temperature conditions depending on the electrical resistance were unknown. In order to overcome the limitations of mass transfer, this work tried to measure the cupric ion concentration. The methods of concentration measurement are RGB, Brightness, ICP, PIV, and Interferometry. The key of RGB, Brightness and PIV method is the clear images of the concentration boundary layer corresponding the thermal boundary layer of heat transfer. The results for ICP method can be got by taking the trace sample of a solution, accurately. The formation of patterns in the interferometry is very important. The characteristics of the interference pattern depend on the nature of the light source, the precise orientation of the mirrors, etc. The methodology of concentration measurement is still under development stage.

  20. Measurement of the Cupric Ion Concentration Variation near Electrodes in the Copper Electroplating System

    International Nuclear Information System (INIS)

    Moon, Je Young; Chung, Bum Jin

    2016-01-01

    The heat fluxes to the side wall imposed at the upper metallic layer, are known to increase with the reduction of layer height. This 'Focusing effect' is varied by cooling condition of upper boundary and height of the metallic layer. The heat transfer experiments were replaced by mass transfer experiments based on the heat and mass transfer analogy concept. When the electroplating system is adopted as the mass transfer system, in order to simulate the different temperature conditions of top and side walls, an electrical resistance was attached to the top wall so that it is mimics hotter wall condition. Because the quantitative temperature conditions according to the electrical resistance were unknown, the methodology development is necessary. The electrical resistance was adopted to the top plate. But the quantitative temperature conditions depending on the electrical resistance were unknown. In order to overcome the limitations of mass transfer, this work tried to measure the cupric ion concentration. The methods of concentration measurement are RGB, Brightness, ICP, PIV, and Interferometry. The key of RGB, Brightness and PIV method is the clear images of the concentration boundary layer corresponding the thermal boundary layer of heat transfer. The results for ICP method can be got by taking the trace sample of a solution, accurately. The formation of patterns in the interferometry is very important. The characteristics of the interference pattern depend on the nature of the light source, the precise orientation of the mirrors, etc. The methodology of concentration measurement is still under development stage.

  1. Solar cycle variation of interstellar neutral He, Ne, O density and pick-up ions along the Earth's orbit

    Science.gov (United States)

    Sokół, Justyna M.; Bzowski, Maciej; Kubiak, Marzena A.; Möbius, Eberhard

    2016-06-01

    We simulated the modulation of the interstellar neutral (ISN) He, Ne, and O density and pick-up ion (PUI) production rate and count rate along the Earth's orbit over the solar cycle (SC) from 2002 to 2013 to verify if SC-related effects may modify the inferred ecliptic longitude of the ISN inflow direction. We adopted the classical PUI model with isotropic distribution function and adiabatic cooling, modified by time- and heliolatitude-dependent ionization rates and non-zero injection speed of PUIs. We found that the ionization losses have a noticeable effect on the derivation of the ISN inflow longitude based on the Gaussian fit to the crescent and cone peak locations. We conclude that the non-zero radial velocity of the ISN flow and the energy range of the PUI distribution function that is accumulated are of importance for a precise reproduction of the PUI count rate along the Earth orbit. However, the temporal and latitudinal variations of the ionization in the heliosphere, and particularly their variation on the SC time-scale, may significantly modify the shape of PUI cone and crescent and also their peak positions from year to year and thus bias by a few degrees the derived longitude of the ISN gas inflow direction.

  2. Sulphur isotope variations in the mantle from ion microprobe analyses of micro-sulphide inclusions

    International Nuclear Information System (INIS)

    Chaussidon, M.; Albarede, F.; Sheppard, S.M.F.

    1989-01-01

    21 samples of sulphide trapped either as liquid globules or grains in various minerals (olivine, pyroxenes, ilmenite and garnet) or rocks (basalt glasses, peridotites, eclogites and kimberlites) of mantle origin, have been analysed for their sulphur isotope, and their Cu, Ni, Fe compositions by ion microprobe. The results show a wide range of δ 34 S values between -4.9±1 and +8±1per mille. Sulphides with high nickel contents (up to 40% pentlandite), corresponding mostly to residual peridotites, have δ 34 S values ranging from -3.2per mille to +3.6per mille with a mode of +3±1per mille, compared to low Ni content sulphides, mostly contained in pyroxenites, OIB and kimberlites, ranging from -3.6per mille to +8per mille with a mode of +1±1per mille. The δ 34 S of sulphides originating from within the mantle are variable. The sulphide globules with high Ni contents and δ 34 S values close to +3per mille, are probably produced by 10-20% partial melting of a mantle source containing 300 ppm sulphur as an upper limit and having a δ 34 S value of +0.5±0.5per mille. This difference in δ 34 S values suggests a high-temperature S-isotope fractionation of ≅+3per mille between liquid sulphide and the sulphur dissolved in the silicate liquid. The sulphur isotopes balance in the system upper mantle + oceanic crust + continental crust + seawater requires a mean δ 34 S value of the primitive upper mantle of +0.5per mille, slightly but significantly different from that of chondrites (+0.2±0.2per mille). (orig.)

  3. Five-year yield variation in N-nitrosonornicotine and (4-methylnitrosoamino)-1-(3-pyridyl)-1-butanone from the smoke of commercial cigarette brands on the Japanese market.

    Science.gov (United States)

    Hyodo, T; Minagawa, K; Mikita, A

    2015-12-01

    This study reports on variation in the yields of N-nitrosonornicotine (NNN) and (4-methylnitrosoamino)-1-(3-pyridyl)-1-butanone (NNK) from the mainstream smoke of cigarette brands and describes factors affecting this variation. Yields of NNN and NNK from smoke and tobacco filler, which is blended and cut tobacco filled in a cigarette tube, together with cigarette design parameters, were measured for 11 commercial cigarette brands, which were available in Japan from 2009 to 2013. The ranges of the relative standard deviations (RSDs) for NNN from the smoke of each brand were 5.0%-29.9% under International Organization for Standardization (ISO) and 6.3%-26.3% under Health Canada Intense (HCI) smoking regime. When these RSDs were compared with those of tar, nicotine, and carbon monoxide yields in each brand, they were found to be much higher for all of the brands under the HCI, and higher for most of the brands under the ISO smoking regime. In addition, the RSDs of NNN and NNK in smoke were mostly higher than those of KY3R4F which was manufactured in a single batch. It was identified that variation in NNN yields from tobacco filler mainly contribute to variation in NNN yields from smoke. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Study of a High-Yield Cellulase System Created by Heavy-Ion Irradiation-Induced Mutagenesis of Aspergillus niger and Mixed Fermentation with Trichoderma reesei

    Science.gov (United States)

    Chen, Ji-Hong; Li, Wen-Jian; Liu, Jing; Hu, Wei; Xiao, Guo-Qing; Dong, Miao-Yin; Wang, Yu-Chen

    2015-01-01

    The aim of this study was to evaluate and validate the efficiency of 12C6+ irradiation of Aspergillus niger (A. niger) or mutagenesis via mixed Trichoderma viride (T. viride) culturing as well as a liquid cultivation method for cellulase production via mixed Trichoderma reesei (T. reesei) and A. niger culture fermentation. The first mutagenesis approach was employed to optimize yield from a cellulase-producing strain via heavy-ion mutagenesis and high-throughput screening, and the second was to effectively achieve enzymatic hydrolysis of cellulase from a mixed culture of mutant T. viride and A. niger. We found that 12C6+-ion irradiation induced changes in cellulase biosynthesis in A. niger but had no effect on the time course of the synthesis. It is notable that the exoglucanases (CBH) activities of A. niger strains H11-1 and H differed (6.71 U/mL vs. 6.01 U/mL) and were significantly higher than that of A. niger mutant H3-1. Compared with strain H, the filter paper assay (FPA), endoglucanase (EG) and β-glucosidase (BGL) activities of mutant strain H11-1 were increased by 250.26%, 30.26% and 34.91%, respectively. A mixed culture system was successfully optimized, and the best ratio of T. reesei to A. niger was 5:1 for 96 h with simultaneous inoculation. The BGL activity of the mixed culture increased after 72 h. At 96 h, the FPA and BGL activities of the mixed culture were 689.00 and 797.15 U/mL, respectively, significantly higher than those of monocultures, which were 408.70 and 646.98 U/mL for T. reesei and 447.29 and 658.89 U/mL for A. niger, respectively. The EG activity of the mixed culture was 2342.81 U/mL, a value that was significantly higher than that of monocultures at 2206.57 U/mL for T. reesei and 1727.62 U/mL for A. niger. In summary, cellulose production and hydrolysis yields were significantly enhanced by the proposed combination scheme. PMID:26656155

  5. Study of a High-Yield Cellulase System Created by Heavy-Ion Irradiation-Induced Mutagenesis of Aspergillus niger and Mixed Fermentation with Trichoderma reesei.

    Directory of Open Access Journals (Sweden)

    Shu-Yang Wang

    Full Text Available The aim of this study was to evaluate and validate the efficiency of 12C6+ irradiation of Aspergillus niger (A. niger or mutagenesis via mixed Trichoderma viride (T. viride culturing as well as a liquid cultivation method for cellulase production via mixed Trichoderma reesei (T. reesei and A. niger culture fermentation. The first mutagenesis approach was employed to optimize yield from a cellulase-producing strain via heavy-ion mutagenesis and high-throughput screening, and the second was to effectively achieve enzymatic hydrolysis of cellulase from a mixed culture of mutant T. viride and A. niger. We found that 12C6+-ion irradiation induced changes in cellulase biosynthesis in A. niger but had no effect on the time course of the synthesis. It is notable that the exoglucanases (CBH activities of A. niger strains H11-1 and H differed (6.71 U/mL vs. 6.01 U/mL and were significantly higher than that of A. niger mutant H3-1. Compared with strain H, the filter paper assay (FPA, endoglucanase (EG and β-glucosidase (BGL activities of mutant strain H11-1 were increased by 250.26%, 30.26% and 34.91%, respectively. A mixed culture system was successfully optimized, and the best ratio of T. reesei to A. niger was 5:1 for 96 h with simultaneous inoculation. The BGL activity of the mixed culture increased after 72 h. At 96 h, the FPA and BGL activities of the mixed culture were 689.00 and 797.15 U/mL, respectively, significantly higher than those of monocultures, which were 408.70 and 646.98 U/mL for T. reesei and 447.29 and 658.89 U/mL for A. niger, respectively. The EG activity of the mixed culture was 2342.81 U/mL, a value that was significantly higher than that of monocultures at 2206.57 U/mL for T. reesei and 1727.62 U/mL for A. niger. In summary, cellulose production and hydrolysis yields were significantly enhanced by the proposed combination scheme.

  6. Softening the ultra-stiff: Controlled variation of Young’s modulus in single-crystal diamond by ion implantation

    International Nuclear Information System (INIS)

    Battiato, A.; Lorusso, M.; Bernardi, E.; Picollo, F.; Bosia, F.; Ugues, D.; Zelferino, A.; Damin, A.; Baima, J.

    2016-01-01

    A combined experimental and numerical study on the variation of the elastic properties of defective single-crystal diamond is presented for the first time, by comparing nano-indentation measurements on MeV-ion-implanted samples with multi-scale modeling consisting of both ab initio atomistic calculations and meso-scale Finite Element Method (FEM) simulations. It is found that by locally introducing defects in the 2 × 10 18 –5 × 10 21  cm −3 density range, a significant reduction of Young’s modulus, as well as of density, can be induced in the diamond crystal structure without incurring in the graphitization of the material. Ab initio atomistic simulations confirm the experimental findings with a good degree of confidence. FEM simulations are further employed to verify the consistency of measured deformations with a stiffness reduction, and to derive strain and stress levels in the implanted region. Combining these experimental and numerical results, we also provide insight into the mechanism responsible for the depth dependence of the graphitization threshold in diamond. This work prospects the possibility of achieving accurate tunability of the mechanical properties of single-crystal diamond through defect engineering, with significant technological applications, e.g. the fabrication and control of the resonant frequency of diamond-based micromechanical resonators.

  7. Sensitivity of Rabbit Ventricular Action Potential and Ca2+ Dynamics to Small Variations in Membrane Currents and Ion Diffusion Coefficients

    Directory of Open Access Journals (Sweden)

    Yuan Hung Lo

    2013-01-01

    Full Text Available Little is known about how small variations in ionic currents and Ca2+ and Na+ diffusion coefficients impact action potential and Ca2+ dynamics in rabbit ventricular myocytes. We applied sensitivity analysis to quantify the sensitivity of Shannon et al. model (Biophys. J., 2004 to 5%–10% changes in currents conductance, channels distribution, and ion diffusion in rabbit ventricular cells. We found that action potential duration and Ca2+ peaks are highly sensitive to 10% increase in L-type Ca2+ current; moderately influenced by 10% increase in Na+-Ca2+ exchanger, Na+-K+ pump, rapid delayed and slow transient outward K+ currents, and Cl− background current; insensitive to 10% increases in all other ionic currents and sarcoplasmic reticulum Ca2+ fluxes. Cell electrical activity is strongly affected by 5% shift of L-type Ca2+ channels and Na+-Ca2+ exchanger in between junctional and submembrane spaces while Ca2+-activated Cl−-channel redistribution has the modest effect. Small changes in submembrane and cytosolic diffusion coefficients for Ca2+, but not in Na+ transfer, may alter notably myocyte contraction. Our studies highlight the need for more precise measurements and further extending and testing of the Shannon et al. model. Our results demonstrate usefulness of sensitivity analysis to identify specific knowledge gaps and controversies related to ventricular cell electrophysiology and Ca2+ signaling.

  8. Ion beam texturing

    Science.gov (United States)

    Hudson, W. R.

    1977-01-01

    A microscopic surface texture was created by sputter-etching a surface while simultaneously sputter-depositing a lower sputter yield material onto the surface. A xenon ion-beam source was used to perform the texturing process on samples as large as 3-cm diameter. Textured surfaces have been characterized with SEM photomicrographs for a large number of materials including Cu, Al, Si, Ti, Ni, Fe, stainless steel, Au, and Ag. A number of texturing parameters are studied including the variation of texture with ion-beam powder, surface temperature, and the rate of texture growth with sputter etching time.

  9. Acceleration of beam ions during major radius compression in TFTR

    International Nuclear Information System (INIS)

    Wong, K.L.; Bitter, M.; Hammett, G.W.

    1985-09-01

    Tangentially co-injected deuterium beam ions were accelerated from 82 keV up to 150 keV during a major radius compression experiment in TFTR. The ion energy spectra and the variation in fusion yield were in good agreement with Fokker-Planck code simulations. In addition, the plasma rotation velocity was observed to rise during compression

  10. Slags in a Large Variation Range of Oxygen Potential Based on the Ion and Molecule Coexistence Theory

    Science.gov (United States)

    Yang, Xue-Min; Li, Jin-Yan; Zhang, Meng; Chai, Guo-Min; Zhang, Jian

    2014-12-01

    A thermodynamic model for predicting sulfide capacity of CaO-FeO-Fe2O3-Al2O3-P2O5 slags in a large variation range of oxygen potential corresponding to mass percentage of FetO from 1.88 to 55.50 pct, i.e., IMCT- model, has been developed by coupling with the deduced desulfurization mechanism of the slags based on the ion and molecule coexistence theory (IMCT). The developed IMCT- model has been verified through comparing the determined sulfide capacity after Ban-ya et al.[20] with the calculated by the developed IMCT- model and the calculated by the reported sulfide capacity models such as the KTH model. Mass percentage of FetO as 6.75 pct corresponding to the mass action concentration of FetO as 0.0637 or oxygen partial as 2.27 × 10-6 Pa is the criterion for distinguishing reducing and oxidizing zones for the slags. Sulfide capacity of the slags in reducing zone is controlled by reaction ability of CaO regardless of slag oxidization ability. However, sulfide capacity of the slags in oxidizing zone shows an obvious increase tendency with the increasing of slag oxidization ability. Sulfide capacity of the slags in reducing zone keeps almost constant with variation of the simplified complex basicity (pct CaO)/((pct Al2O3) + (pct P2O5)), or optical basicity, or the mass action concentration ratios of N FeO/ N CaO, , , and . Sulfide capacity of the slags in oxidizing zone shows an obvious increase with the increasing of the simplified complex basicity (pct CaO)/((pct Al2O3) + (pct P2O5)) or optical basicity, or the aforementioned mass action concentration ratios. Thus, the aforementioned mass action concentration ratios and the corresponding mass percentage ratios of various iron oxides to basic oxide CaO are recommended to represent the comprehensive effect of various iron oxides and basic oxide CaO on sulfide capacity of the slags.

  11. Design of DC-60 cyclotron with the fair ion energy variation for the Inter-disciplinary laboratory complex by L.N. Gumilev Eurasian State University

    International Nuclear Information System (INIS)

    Gukal, B.N.; Itkis, M.G.; Dmitriev, S.N.; Gul'bekyan, G.G.; Franko, J.; Kadyrzhanov, K.K.; Arzumanov, A.A.; Borisenko, A.N.; Lysukhin, S.N.

    2003-01-01

    The DC-60 heavy ions cyclotron pre-design project is implemented. The cyclotron is the key facility of the Inter-disciplinary laboratory complex by L.N. Gumilev Eurasian State University. In comparison with previous project in a new one the possibility for fair variation of the ions energies on 30 % at the expense of magnetic field level change is planed. The magnet structure of the cyclotron allowing to vary the magnet field from 1.25 to 1.65 T with use the low-power magnet coils system is found. The accelerator provides the opportunity for the ions acceleration from Li to Xe with energies from 0.4 to 1.6 MeV/nucleon. The exterior ion source of the ECR type will be planing to use on the cyclotrons and axial beam injection system development will be created. The extending voltage on the ion source is 10-25 kV. For experiments conducting on the cyclotron complex is expecting to create on channel for low energy beams - 10-25 kV per charge (ECR source beams) and three withdrawn channels for accelerated ion beams, one of those will be packaged with necessary equipment for the nuclear filters manufacture. The cyclotron complex will be used for both the fulfillment of a wide range of scientific and applied problems and a students training

  12. Computer simulation and data compilation of sputtering yield by hydrogen isotopes ({sup 1}H{sup +}, {sup 2}D{sup +}, {sup 3}T{sup +}) and helium ({sup 4}He{sup +}) ion impact from monatomic solids at normal incidence

    Energy Technology Data Exchange (ETDEWEB)

    Yamamura, Yasunori; Sakaoka, Kazuho; Tawara, Hiro

    1995-10-01

    The ion-induced sputtering yields from monatomic solids at normal incidence are presented graphically for light-ion ({sup 1}H{sup +}, {sup 2}D{sup +}, {sup 3}T{sup +}, {sup 4}He{sup +}) bombardment on various target materials as a function of the incident ion energy. To supplement the experimental data, the sputtering yields are calculated by the Monte Carlo simulation code ACAT for all possible light ion-target combinations. Each graph shows the available experimental and ACAT data points, together with the sputtering yield calculated by the Yamamura and Tawara empirical formula. (author).

  13. Equity yields

    NARCIS (Netherlands)

    Vrugt, E.; van Binsbergen, J.H.; Koijen, R.S.J.; Hueskes, W.

    2013-01-01

    We study a new data set of dividend futures with maturities up to ten years across three world regions: the US, Europe, and Japan. We use these asset prices to construct equity yields, analogous to bond yields. We decompose the equity yields to obtain a term structure of expected dividend growth

  14. Maize (Zea mays L.) yield response to nitrogen as influenced by spatio-temporal variations of soil-water-topography dynamics

    Science.gov (United States)

    Reducing nitrogen (N) loss from agricultural lands and applying N fertilizer at rates that satisfy both economic and environmental objectives is critical for sustainable agricultural management. This study investigated spatial variability in maize yield response to N and its controlling factors alon...

  15. Phenological Variation and its Relation with Yield in several Wheat (Triticum aestivum L. Cultivars under Normal and Late Sowing Mediated Heat Stress Condition

    Directory of Open Access Journals (Sweden)

    Kamrun NAHAR

    2010-09-01

    Full Text Available Phenological performance in relation to yield of five modern varieties of wheat Sourav, Pradip, Sufi, Shatabdi and Bijoy were evaluated under two growing environments; one is normal growing environment (sowing at November 30 and the other is post anthesis heat stressed environment (sowing at December 30. In case of late seeding, the varieties phased a significant level of high temperature stress that also significantly affected the required days to germination, booting, anthesis, maturity of all varieties including the yield as compared to normal sowing treatment. The temperature during the grain filling or grain maturing period was near 23C in case of normal seeding and it was near about 28C to 30C and sometimes reached above this range in the later period of late seeded treatment. In the normal sowing treatment the germination period was lower than the late sowing treatment as during that time the temperature was higher as compared to late sowing condition where temperature was lower. Days to anthesis and booting decreased due to late sown heat stress condition regardless the cultivars. These phenological characteristics under heat stressed condition led the wheat cultivars to significantly lower the grain yield as compared to normal condition. Due to heat stress, the yield reduction was 69.53% in Sourav, 58.41% in Pradip, 73.01% in Sufi, 55.46% in Shatabdi and 53.42% in Bijoy.

  16. Variation in the sugar yield in response to drying-off of sugarcane before harvest and the occurrence of low air temperatures

    Directory of Open Access Journals (Sweden)

    Renato Araújo

    2016-03-01

    Full Text Available ABSTRACT The need to irrigate sugarcane in the Brazilian Savanna is due to the lack of rain from April to September. For efficient sugar accumulation, the crop needs water stress or heat stress at the maturation stage. However, when the water deficit is intense at this stage, it occurs the reduction in crop production. The objective of this study was: (i to assess the quality of the raw material of sugarcane in different drying-off seasons before harvest; (ii to evaluate the influence of heat stress on the culture. The experiment was conducted in Santo Antônio de Goiás (GO, Brazil, in Oxisol, with CTC4 variety in cane-plant cycle. A randomized block design in a split-plot array in time was used. The treatments of the plots were five drying-off times (90, 60, 30, 15 and 0 days before harvest and, in the subplots, five seasons of the yield evaluation. Irrigation was carried out by surface drip method, which provided 50% of crop water requirement. The best results for sugar yield occurred 30 days before harvest, period in which the crop irrigation could be interrupted. The water deficit of 37.76 mm appears to be the critical limit of water shortage in the soil, from which the sugarcane yield starts to be reduced. The sugar concentration in the stalk was more influenced by low air temperatures than sugarcane yield.

  17. Effect of variation in the glass-former network structure on the relaxation properties of conductive Ag+ ions in AgI-based fast ion conducting glasses

    Science.gov (United States)

    Hanaya, Minoru; Nakayama, Michiko; Hatate, Atsuo; Oguni, Masaharu

    1995-08-01

    Heat capacities and ac conductivities of AgI-based fast ion conducting glasses of AgI-Ag2O-P2O5 and AgI-Ag2O-B2O3 systems with different P-O or B-O network structures but with the same AgI concentration of 1.55×104 mol m-3 were measured in the temperature range 14-400 K and in the temperature and frequency ranges 100-200 K and 10 Hz-1 MHz, respectively. The β-glass transition due to a freezing-in of the rearrangement of Ag+ ions was observed by adiabatic calorimetry for the glasses in the liquid-nitrogen temperature region, and the conductometry was suggested to see the same mode of Ag+-ion motion as the calorimetry. It was found that the development of the network structure of the glass former at constant AgI concentration resulted in the decrease of the β-glass transition temperature and the activation energy for the diffusional motion of Ag+ ions and in the increase of the heat-capacity jump associated with the glass transition. The results support the amorphous AgI aggregate model for the structure of the conductive region in the glasses with relatively high AgI compositions, indicating that Ag+-ion conductivity is mainly dominated by the degree of development of the AgI aggregate region dependent on the glass-former network structure as well as the AgI composition.

  18. Effect of variation in proportion of cornmeal and steam-rolled corn in diets for dairy cows on behavior, digestion, and yield and composition of milk.

    Science.gov (United States)

    Uchida, K; Ballard, C S; Mandebvu, P; Sniffen, C J; Carter, M P

    2001-02-01

    Sixty-six lactating multiparous Holstein cows (113+/-46 DIM) housed in a free-stall facility were blocked and assigned randomly to one of three treatments to evaluate the effects on animal performance from feeding cornmeal, cornmeal mixed with steam-rolled corn in a ratio of 1:1 on dry matter basis, or steam-rolled corn. The only difference in the dietary ingredients was the type of corn, which was included in the total mixed ration (TMR) at 17% of dry matter. The densities (g/L) of cornmeal and steam-rolled corn were, respectively, 635 and 553. Diets were fed as TMR and were formulated according to the Cornell Penn Miner Dairy nutrition model. The TMR consisted of 40% forage and 60% concentrate on dry matter basis. The first 2 wk of the 8-wk study was a preliminary period, and data collected during this period were used as covariate in statistical analysis of production data collected during wk 6 to 8. Treatment diets were fed from wk 3 to 8. Total tract digestibilities of dry matter, organic matter, crude protein, starch, and neutral detergent fiber were not significantly different among treatments. Cows fed TMR containing steam-rolled corn had higher body condition and ruminated longer. However, feeding cornmeal and steam-rolled corn together did not improve dry matter and nutrient digestion, milk yield, 3.5% fat-corrected milk yield, and percentage and yield of fat, crude protein, true protein, and lactose in milk, and milk urea nitrogen. In conclusion, feeding steam-rolled corn improved animal body condition and rumination. Partial or complete substitution of cornmeal by steam-rolled corn in diets for lactating dairy cows did not improve dry matter and nutrient digestion, milk yield, and milk composition.

  19. Phenological Variation and its Relation with Yield in several Wheat (Triticum aestivum L. Cultivars under Normal and Late Sowing Mediated Heat Stress Condition

    Directory of Open Access Journals (Sweden)

    Kamrun NAHAR

    2010-09-01

    Full Text Available Phenological performance in relation to yield of five modern varieties of wheat �Sourav�, �Pradip�, �Sufi�, �Shatabdi� and �Bijoy� were evaluated under two growing environments; one is normal growing environment (sowing at November 30 and the other is post anthesis heat stressed environment (sowing at December 30. In case of late seeding, the varieties phased a significant level of high temperature stress that also significantly affected the required days to germination, booting, anthesis, maturity of all varieties including the yield as compared to normal sowing treatment. The temperature during the grain filling or grain maturing period was near 23�C in case of normal seeding and it was near about 28�C to 30�C and sometimes reached above this range in the later period of late seeded treatment. In the normal sowing treatment the germination period was lower than the late sowing treatment as during that time the temperature was higher as compared to late sowing condition where temperature was lower. Days to anthesis and booting decreased due to late sown heat stress condition regardless the cultivars. These phenological characteristics under heat stressed condition led the wheat cultivars to significantly lower the grain yield as compared to normal condition. Due to heat stress, the yield reduction was 69.53% in �Sourav�, 58.41% in �Pradip�, 73.01% in �Sufi�, 55.46% in �Shatabdi� and 53.42% in �Bijoy�.

  20. Seasonal Variations and Correlation Analysis of Water-Soluble Inorganic Ions in PM2.5 in Wuhan, 2013

    Directory of Open Access Journals (Sweden)

    Ting Huang

    2016-03-01

    Full Text Available Daily PM2.5 and water-soluble inorganic ions (NH4+, SO42−, NO3−, Cl−, Ca2+, Na+, K+, Mg2+ were collected at the Hongshan Air Monitoring Station at the China University of Geosciences (Wuhan (30°31′N, 114°23′E, Wuhan, from 1 January to 30 December 2013. A total of 52 effective PM2.5 samples were collected using medium flow membrane filter samplers, and the anionic and cationic ions were determined by ion chromatography and ICP, respectively. The results showed that the average mass concentration of the eight ions was 40.96 µg/m3, which accounted for 62% of the entire mass concentration. In addition, the order of the ion concentrations was SO42− > NO3− > NH4+ > Cl− >K+ > Ca2+ > Na+ > Mg2+. The secondary inorganic species SO42−, NO3− and NH4+ were the major components of water-soluble ions in PM2.5, with a concentration of 92% of the total ions of PM2.5, and the total concentrations of the three ions in the four seasons in descending order as follows: winter, spring, autumn, and summer. NH4+ had a significant correlation with SO42− and NO3−, and the highest correlation coefficients were 0.943 and 0.923 (in winter, while the minimum coefficients were 0.683 and 0.610 (in summer. The main particles were (NH42SO4 and NH4NO3 in PM2.5. The charge of the water-soluble ions was nearly balanced in PM2.5, and the pertinence coefficients of water-soluble anions and cations were more than 0.9. The highest pertinence coefficients were in the spring (0.9887, and the minimum was in summer (0.9459. That is, there were more complicated ions in PM2.5 in the summer. The mean value of NO3−/SO42− was 0.64, indicating that stationary sources of PM2.5 had a greater contribution in Wuhan.

  1. Incident ion charge state dependence of electron emission during slow multicharged ion-surface interactions

    International Nuclear Information System (INIS)

    Hughes, I.G.; Zeijlmans van Emmichoven, P.A.; Havener, C.C.; Overbury, S.H.; Robinson, M.T.; Zehner, D.M.; Meyer, F.W.

    1992-01-01

    Characteristic variations in the total electron yield γ as a function of crystal azimuthal orientation are reported for slow N 2+ , N 5+ and N 6+ ions incident on a Au(011) single crystal, together with measurements of γ as a function of incident ion velocity. Kinetic electron emission is shown to arise predominantly in close collisions between incident ions and target atoms, and potential electron emission is found to be essentially constant within our present velocity range. The incident ion charge state is shown to play no role in kinetic electron emission. Extremely fast neutralization times of the order of 10 - 15 secs are needed to explain the observations

  2. High-throughput phenotyping (HTP) identifies seedling root traits linked to variation in seed yield and nutrient capture in field-grown oilseed rape (Brassica napus L.).

    Science.gov (United States)

    Thomas, C L; Graham, N S; Hayden, R; Meacham, M C; Neugebauer, K; Nightingale, M; Dupuy, L X; Hammond, J P; White, P J; Broadley, M R

    2016-04-06

    Root traits can be selected for crop improvement. Techniques such as soil excavations can be used to screen root traits in the field, but are limited to genotypes that are well-adapted to field conditions. The aim of this study was to compare a low-cost, high-throughput root phenotyping (HTP) technique in a controlled environment with field performance, using oilseed rape (OSR;Brassica napus) varieties. Primary root length (PRL), lateral root length and lateral root density (LRD) were measured on 14-d-old seedlings of elite OSR varieties (n = 32) using a 'pouch and wick' HTP system (∼40 replicates). Six field experiments were conducted using the same varieties at two UK sites each year for 3 years. Plants were excavated at the 6- to 8-leaf stage for general vigour assessments of roots and shoots in all six experiments, and final seed yield was determined. Leaves were sampled for mineral composition from one of the field experiments. Seedling PRL in the HTP system correlated with seed yield in four out of six (r = 0·50, 0·50, 0·33, 0·49;P emergence in three out of five (r = 0·59, 0·22, 0·49;P emergence, general early vigour or yield in the field. Associations between PRL and field performance are generally related to early vigour. These root traits might therefore be of limited additional selection value, given that vigour can be measured easily on shoots/canopies. In contrast, LRD cannot be assessed easily in the field and, if LRD can improve nutrient uptake, then it may be possible to use HTP systems to screen this trait in both elite and more genetically diverse, non-field-adapted OSR. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company.

  3. Variation of milk coagulation properties, cheese yield, and nutrients recovery in curd of cows of different breeds before, during and after transhumance to highland summer pastures.

    Science.gov (United States)

    Zendri, Francesco; Ramanzin, Maurizio; Cipolat-Gotet, Claudio; Sturaro, Enrico

    2017-02-01

    This paper aimed at evaluating the effect of summer transhumance to mountain pastures of dairy cows of different breeds on cheese-making ability of milk. Data were from 649 dairy cows of specialized (Holstein Friesian and Brown Swiss) dual purpose (Simmental) and local (mostly Rendena and Alpine Grey) breeds. The Fourier-Transform Infra-Red Spectra (FTIRS) of their milk samples were collected before and after transhumance in 109 permanent dairy farms, and during transhumance in 14 summer farms (with multi-breeds herds) of the Trento Province, north-eastern Italy. A variety of 18 traits describing milk coagulation, curd firming, cheese yield and nutrients recovery in curd/loss in whey were predicted on the basis of FTIRS collected at the individual cow level. Moving the cows to summer farms improved curd firming traits but reduced cheese yields because of an increase of water and fat lost in the whey. During summer grazing, most of cheese-making traits improved, often non-linearly. The milk from summer farms supplementing cows with more concentrates showed better curd firming and cheese yield, because of lower fat lost in the whey. The breed of cows affected almost all the traits with a worst cheese-making ability for milk samples of Holsteins through all the trial, and interacted with concentrate supplementation because increasing compound feed tended to improve cheese-making traits for all breed, with the exception of local breeds for coagulation time and of Brown Swiss for curd firming time. In general, summer transhumance caused a favourable effect on cheese-making aptitude of milk, even though with some difference according to parity, initial days in milk, breed and concentrate supplementation of cows.

  4. The use of macro and micro proton beams to study the variation in PIXE yield from metal targets insulated with PTFE, glass and nylon

    International Nuclear Information System (INIS)

    Pillay, A.E.

    1999-01-01

    Proton beams of diameters of 3 mm and 3 μm, were used to observe the differences in PIXE yield from pure metal targets encapsulated with PTFE, glass (macor) and nylon. The beam energy was kept constant at 700 keV. Beam currents varied from about 200 pA with the microbeam and between 1-10 nA with the macrobeam. Considerable enhancement was observed mainly with the use of PTFE, up to about a factor of 18 with the macrobeam and 306 with the microbeam. (author)

  5. BaSnF4 fast ion conductor: Variations versus the method of preparation and anomalous temperature variation of the quadrupole splitting

    International Nuclear Information System (INIS)

    Hantash, Jamil; Bartlett, Alan; Denes, Georges; Muntasar, Abdualhafeed; Oldfield, Philip

    2005-01-01

    A new method of preparation of high performance fluoride ion conductor, BaSnF 4 , by water leaching of newly discovered barium tin(II) chloride fluorides, has been designed, and the materials have been studied and compared to the solid prepared by the usual dry method. The unit-cell parameters and crystallite dimensions were found to vary with the method of preparation. In addition, the crystallite dimensions were found to be highly anisotropic for the samples obtained by the wet method. The Moessbauer spectrum is made of a large tin(II) quadrupole doublet, and a broad tin(IV) oxide peak due to surface oxidation. The tin(II) spectrum is in agreement with covalently bonded tin(II) having a strongly stereoactive lone pair. An unusually high dependence of the quadrupole splitting at low temperatures was observed (5.8 times larger than for α-SnF 2 ).

  6. Water-soluble ions in atmospheric aerosols measured in five sites in the Yangtze River Delta, China: Size-fractionated, seasonal variations and sources

    Science.gov (United States)

    Wang, Honglei; Zhu, Bin; Shen, Lijuan; Xu, Honghui; An, Junlin; Xue, Guoqiang; Cao, Jinfei

    2015-12-01

    In order to investigate the regional variations of water-soluble ions (WSIs), size-resolved measurement of aerosol particles and WSIs was conducted by using Anderson Sampler and Ion Chromatography at five sites (Nanjing, Suzhou, Lin'an, Hangzhou and Ningbo) in the Yangtze River Delta (YRD) region, China in the Autumn of 2012 and Winter, Spring and Summer of 2013. WSIs exhibited obvious seasonal variations due to the monsoon conversion, with the highest level in winter and lowest level in summer. The aerosol mass concentrations and WSIs in different size segments varied with four seasons. The dominant ions concentrations in PM2.1 ranked in the order of SO42- > NO3- > NH4+ > Cl- > K+ > Ca2+, and the dominant ions concentrations in PM2.1-10 ranked in the order of Ca2+ > NO3- > SO42- > Cl- > NH4+ > Na+. The size spectra of mass and WSIs concentration peaked mostly at 0.43-0.65 μm in four seasons. The concentration discrepancies of WSIs in different cities were caused by the geographic locations and emission source. It's belonged to ammonium-rich distribution in PM2.1 and ammonium-poor distribution in PM2.1-10 in the YRD region. The impact of temperature on mass concentrations of NO3- and NH4+ in PM2.1 were stronger than those in PM2.1-10. PCA analysis shows that the sources of WSIs dominant by anthropogenic sources, soil particles or falling dust, sea salt and burning process.

  7. Highly accurate bound state calculations of the two-center molecular ions by using the universal variational expansion for three-body systems

    Science.gov (United States)

    Frolov, Alexei M.

    2018-03-01

    The universal variational expansion for the non-relativistic three-body systems is explicitly constructed. This universal expansion can be used to perform highly accurate numerical computations of the bound state spectra in various three-body systems, including Coulomb three-body systems with arbitrary particle masses and electric charges. Our main interest is related to the adiabatic three-body systems which contain one bound electron and two heavy nuclei of hydrogen isotopes: the protium p, deuterium d and tritium t. We also consider the analogous (model) hydrogen ion ∞H2+ with the two infinitely heavy nuclei.

  8. Effects of species diversity on seasonal variation in herbage yield and nutritive value of seven binary grass-legume mixtures and pure grass under cutting

    DEFF Research Database (Denmark)

    Elgersma, Anjo; Søegaard, Karen

    2016-01-01

    Intensively managed sown temperate grasslands are generally of low species diversity, although swards based on grass-legume mixtures may have superior productivity and herbage quality than grass-only swards. We conducted a cutting experiment over two years to test the effect of species composition...... and diversity on herbage yield, contents of N, neutral detergent fibre (NDF) and in vitro organic matter digestibility (IVOMD). Perennial ryegrass (PR, Lolium perenne) was sown alone and with each of four forage legumes: red clover (RC, Trifolium pratense), lucerne (LU, Medicago sativa), birdsfoot trefoil (BT......, Lotus corniculatus) and white clover (WC, Trifolium repens); WC was also sown with hybrid ryegrass (HR, Lolium × boucheanum), meadow fescue (MF, Festuca pratensis) and timothy (TI, Phleum pratense). Herbage productivity was lowest in pure PR followed by PR/BT, and highest in PR/RC; this mixture had...

  9. Variations in Essential Oil Yield, Composition, and Antioxidant Activity of Different Plant Organs from Blumea balsamifera (L.) DC. at Different Growth Times.

    Science.gov (United States)

    Yuan, Yuan; Huang, Mei; Pang, Yu-Xin; Yu, Fu-Lai; Chen, Ce; Liu, Li-Wei; Chen, Zhen-Xia; Zhang, Ying-Bo; Chen, Xiao-Lu; Hu, Xuan

    2016-08-05

    Blumea balsamifera, also named Ainaxiang, is widely used as an ancient medicinal herb in tropical and subtropical Asia. It is rich in essential oils. In this work the essential oils of B. balsamifera from different plant organs and in different months were extracted, and then analyzed by gas chromatography-mass spectrometry. The results showed that essential oil yield of young leaves was the highest (0.65 mL/100 g), followed by mature leaves (0.57 mL/100 g), and the oil yield was higher in October (0.47 mL/100 g) than other months. A total of 44 compounds were identified, representing 92.64%-96.71% of the oil. Eighteen common chemical components were found among the six plant organs, representing >80% of the oil constituents. l-borneol was the main ingredient in leaves, and its content was the highest in senescent leaves and in December. In the essential oils of young shoots and young stems, the main component was dimethoxydurene. Antioxidant activity was also determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-carotene bleaching (BCB) assays. The results indicated that the β-carotene bleaching activity was far stronger than the DPPH radical-scavenging capacity, and the young leaves and young shoots showed stronger antioxidant activity. Dimethoxydurene, β-caryophyllene, and α-caryophyllene play a positive role in good antioxidant activity, while β-eudesmol, phytol, and tetradecanal play a negative role. The antioxidant activity revealed in this study might help in developing this promising bioresource for use in the medicinal and cosmetic industries.

  10. Seasonal variations in size distribution, water-soluble ions, and carbon content of size-segregated aerosols over New Delhi.

    Science.gov (United States)

    Kumar, Pawan; Kumar, Sushil; Yadav, Sudesh

    2018-02-01

    Size distribution, water-soluble inorganic ions (WSII), and organic carbon (OC) and elemental carbon (EC) in size-segregated aerosols were investigated during a year-long sampling in 2010 over New Delhi. Among different size fractions of PM 10 , PM 0.95 was the dominant fraction (45%) followed by PM 3-7.2 (20%), PM 7.2-10 (15%), PM 0.95-1.5 (10%), and PM 1.5-3 (10%). All size fractions exceeded the ambient air quality standards of India for PM 2.5 . Annual average mass size distributions of ions were specific to size and ion(s); Ca 2+ , Mg 2+ , K + , NO 3 - , and Cl - followed bimodal distribution while SO 4 2- and NH 4 + ions showed one mode in PM 0.95 . The concentrations of secondary WSII (NO 3 - , SO 4 2- , and NH 4 + ) increased in winters due to closed and moist atmosphere whereas open atmospheric conditions in summers lead to dispersal of pollutants. NH 4 + and Ca 2+ were dominant neutralization ions but in different size fractions. The summer-time dust transport from upwind region by S SW winds resulted in significantly high concentrations of PM 0.95 and PM 3-7.2 and PM 7.2-10 . This indicted influence of dust generation in Thar Desert and its transport is size selective in nature in downwind direction. The mixing of different sources (geogenic, coal combustions, biomass burning, plastic burning, incinerators, and vehicular emissions sources) for soluble ions in different size fractions was noticed in principle component analysis. Total carbon (TC = EC + OC) constituted 8-31% of the total PM 0.95 mass, and OC dominated over EC. Among EC, char (EC1) dominated over soot (EC2 + EC3). High SOC contribution (82%) to OC and OC/EC ratio of 2.7 suggested possible role of mineral dust and high photochemical activity in SOC production. Mass concentrations of aerosols and WSII and their contributions to each size fraction of PM 10 are governed by nature of sources, emission strength of source(s), and seasonality in meteorological parameters.

  11. Variations of plasmaspheric field-aligned electron and ion densities (90-4000 km) during quiet to moderately active (Kp < 4) geomagnetic conditions

    Science.gov (United States)

    Sonwalkar, V. S.; Reddy, A.

    2017-12-01

    Variation in field-aligned electron and ion densities as a function of geomagnetic activity are important parameters in the physics of the thermosphere-ionosphere-magnetosphere coupling. Using whistler mode sounding from IMAGE, we report variations in field-aligned electron density and O+/H+ transition height (HT) during two periods (16-23 Aug 2005; 24 Sep-06 Oct 2005) when geomagnetic conditions were quiet (maximum Kp in the past 24 hours, Kpmax,24 ≤ 2) to moderately active (2 quiet time, during moderate geomagnetic activity: (1) O+/H+ transition height was roughly same; (2) electron density variations below HT showed no trend; (3) electron density above HT increased ( 10-40 %). The measured electron density is in agreement with in situ measurements from CHAMP (350 km) and DMSP (850 km) and past space borne (e. g., ISIS) measurements but the F2 peak density is a factor of 2 lower relative to that measured by ground ionosondes and that predicted by IRI-2012 empirical model. The measured transition height is consistent with OGO 4, Explorer 31, and C/NOFS measurements but is lower than that from IRI-2012. The observed variations in electron density at F2 peak are consistent with past work and are attributed to solar, geomagnetic, and meteorological causes [e. g. Risibeth and Mendillo, 2001; Forbes et al., 2000]. To the best of our knowledge, variations in field-aligned electron density above transition height at mid-latitudes during quiet to moderately active periods have not been reported in the past. Further investigation using physics based models (e. g., SAMI3) is required to explain the observed variations.

  12. Brazilian Soybean Yields and Yield Gaps Vary with Farm Size

    Science.gov (United States)

    Jeffries, G. R.; Cohn, A.; Griffin, T. S.; Bragança, A.

    2017-12-01

    Understanding the farm size-specific characteristics of crop yields and yield gaps may help to improve yields by enabling better targeting of technical assistance and agricultural development programs. Linking remote sensing-based yield estimates with property boundaries provides a novel view of the relationship between farm size and yield structure (yield magnitude, gaps, and stability over time). A growing literature documents variations in yield gaps, but largely ignores the role of farm size as a factor shaping yield structure. Research on the inverse farm size-productivity relationship (IR) theory - that small farms are more productive than large ones all else equal - has documented that yield magnitude may vary by farm size, but has not considered other yield structure characteristics. We examined farm size - yield structure relationships for soybeans in Brazil for years 2001-2015. Using out-of-sample soybean yield predictions from a statistical model, we documented 1) gaps between the 95th percentile of attained yields and mean yields within counties and individual fields, and 2) yield stability defined as the standard deviation of time-detrended yields at given locations. We found a direct relationship between soy yields and farm size at the national level, while the strength and the sign of the relationship varied by region. Soybean yield gaps were found to be inversely related to farm size metrics, even when yields were only compared to farms of similar size. The relationship between farm size and yield stability was nonlinear, with mid-sized farms having the most stable yields. The work suggests that farm size is an important factor in understanding yield structure and that opportunities for improving soy yields in Brazil are greatest among smaller farms.

  13. Development of methodics for the characterization of the composition of the ion-collision-induced secondary-particle flux by comparison of the yield contributions of photoinduced ion formation processes; Entwicklung einer Methodik zur Charakterisierung der Zusammensetzung des ionenbeschussinduzierten Sekundaerteilchenflusses durch Vergleich der Ausbeuteanteile photoinduzierter Ionenbildungsprozesse

    Energy Technology Data Exchange (ETDEWEB)

    Vering, Guido

    2008-10-13

    The aim of this work was to develop a method to distinguish between different ion formation processes and to determine the influence of these processes on the total number of detected monatomic ions of a certain element. A vector/matrix-formalism was developed, which describes the physical processes of sputtering, ion formation, mass separation and detection in laser-SNMS. In the framework of the method developed, based on this theoretic formalism, changes in the secondary flux contribution of the respective element were observed by comparing the detected monatomic ion yield obtained in specifically aligned (SIMS and) laser-SNMS experiments. The yields resulting from these experiments were used to calculate characteristic numbers to compare the flux composition from different surfaces. The potential of the method was demonstrated for the elements boron, iron and gadolinium by investigating the changes in the flux composition of secondary particles sputtered from metallic surfaces, as a function of the oxygen concentration at the surface. Finally, combined laser-SNMS depth profiles and images, obtained with both laser systems, were presented to demonstrate how the parallel detection of the three differently originated ion signals of the same element can be used to get additional information about the composition of the flux of secondary particles synchronously during the analysis of elemental distributions. In this respect the presented method can be a very helpful tool to prevent misleading interpretations of SIMS or laser-SNMS data. (orig.)

  14. Water-soluble ions in atmospheric aerosols measured in Xi'an, China: Seasonal variations and sources

    Science.gov (United States)

    Zhang, T.; Cao, J. J.; Tie, X. X.; Shen, Z. X.; Liu, S. X.; Ding, H.; Han, Y. M.; Wang, G. H.; Ho, K. F.; Qiang, J.; Li, W. T.

    2011-10-01

    Daily PM 2.5 and water-soluble inorganic ions (Na +, NH 4+, K +, Mg 2+, Ca 2+, Cl -, NO 3- and SO 42-) were collected in Xi'an (34.23°N, 108.88°E), China from March 2006 to March 2007. PM 2.5 was collected using battery-powered mini-volume samplers. And the ions were determined by ion chromatography from the measured aerosol mass. The annual average mass concentration of PM 2.5 was found to be 194.1 ± 78.6 μg m - 3 , which exceeded substantially the international guidelines for health concerns. The seasonal average mass concentration of PM 2.5 was highest in winter (266.8 μg m - 3 ) and lowest in summer (138.6 μg m - 3 ). The three highest abundant ions were SO 42-, NO 3-, and NH 4+, with average concentrations of 35.6 ± 19.5 μg m - 3 , 16.4 ± 10.1 μg m - 3 , and 11.4 ± 6.8 μg m - 3 , which were accounted for 18.7%, 8.0%, and 5.7% of the PM 2.5 mass, respectively. The major ions were in the species of (NH 4) 2SO 4, NH 4HSO 4 and NH 4NO 3, and their concentrations were highest in winter, due to high coal combustion. The concentrations of Ca 2+ were higher in spring than other seasons, due to the higher mineral dust concentrations. Ca 2+ was strongly correlated with CO 32-, which was calculated as the difference in the measured cations minus anions. Ion balance calculations indicate that the PM 2.5 was acidic, and this result is consistent with the measurement of pH values. Sulfur oxidation ratio was higher in summer and autumn, which implies that the formation of secondary sulfate-rich particles is favored by warm and relatively moist weather. Nitrogen oxidation ratio was highest in autumn.

  15. Seasonal variations and size distributions of water-soluble ions of atmospheric particulate matter at Shigatse, Tibetan Plateau.

    Science.gov (United States)

    Yang, Yongjie; Zhou, Rui; Yan, Yan; Yu, Yue; Liu, Junqing; Di, Yi'an; Du, Zhenyu; Wu, Dan

    2016-02-01

    Size-segregated atmospheric particulate matter (PM) samples were collected from July 2012 to September 2013 at Shigatse, high-altitude (3836 m above sea level) site on the south Tibetan Plateau (TP); objectives were to determine the characteristics and size distribution of water-soluble ions (WSIs). Eight major WSIs (Na(+), K(+), Mg(2+), Ca(2+), NH4(+), Cl(-), SO4(2-), and NO3(-)) were detected by ion chromatography. The total concentrations of WSIs were 6370 ± 1916 ng m(-3) in dry season (October - December, January - April), and 5261 ± 769 ng/m(3) during wet phase (May - September). The contribution of K(+) (130 ng m(-3)), Cl(-) (2035 ng m(-3)), SO4(2-) (1176 ng m(-3)), and NO3(-) (706 ng m(-3))(-)were significantly enhanced in dry season, and that of Na(+) (455 ng m(-3)), Mg(2+)(65.4 ng m(-3)), Ca(2+)(1034 ng m(-3)), and NH4(+) (1948 ng m(-3)) were significantly enhanced during wet phase. Mg(2+) and Ca(2+) were concentrated in the coarse mode, and the other ions concentrated in fine mode and coarse mode during two seasons. The correlation coefficients between K(+) and NH4(+), Cl(-), SO4(2-) and NO3(-) were 0.58 (P burning in dry season. The significant correlation between NH4(+) and HCO3(-) which were calculated by ion balance (r = 0.89, P < 0.01), suggesting the source from nitrogen fertilizers during wet phase. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. application of yield line the ion of yield line theory in pre ion of yield

    African Journals Online (AJOL)

    User

    for manufacturing equipment that i vibration sensitive. ... procedure based on the use of certain .... For continuous supports, i1. =i2 = 1 .... YLRGT has facilitated the improved analysis of pre-cast ... Engineering Magazine,March 2005 edition.

  17. Noble-gas ion sputtering yield of gold and copper: Dependence on the energy and angle of incidence of the projectiles

    Energy Technology Data Exchange (ETDEWEB)

    Oliva-Florio, A.; Baragiola, R.A.; Jakas, M.M.; Alonso, E.V.; Ferron, J.

    1987-02-15

    We have measured the sputtering yield of Au and Cu targets as a function of energy and the angle of incidence of noble-gas projectiles in the energy range 2--50 keV. The experimental results were compared with the analytical theory of sputtering and with computer simulations. Our study indicates that the linear-cascade model is applicable only asymptotically for low nuclear stopping powers.

  18. High-dynamic-range neutron time-of-flight detector used to infer the D(t,n){sup 4}He and D(d,n){sup 3}He reaction yield and ion temperature on OMEGA

    Energy Technology Data Exchange (ETDEWEB)

    Forrest, C. J., E-mail: cforrest@lle.rochester.edu; Glebov, V. Yu.; Goncharov, V. N.; Knauer, J. P.; Radha, P. B.; Regan, S. P.; Romanofsky, M. H.; Sangster, T. C.; Shoup, M. J.; Stoeckl, C. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299 (United States)

    2016-11-15

    Upgraded microchannel-plate–based photomultiplier tubes (MCP-PMT’s) with increased stability to signal-shape linearity have been implemented on the 13.4-m neutron time-of-flight (nTOF) detector at the Omega Laser Facility. This diagnostic uses oxygenated xylene doped with diphenyloxazole C{sub 15}H{sub 11}NO + p-bis-(o-methylstyryl)-benzene (PPO + bis-MSB) wavelength shifting dyes and is coupled through four viewing ports to fast-gating MCP-PMT’s, each with a different gain to allow one to measure the light output over a dynamic range of 1 × 10{sup 6}. With these enhancements, the 13.4-m nTOF can measure the D(t,n){sup 4}He and D(d,n){sup 3}He reaction yields and average ion temperatures in a single line of sight. Once calibrated for absolute neutron sensitivity, the nTOF detectors can be used to measure the neutron yield from 1 × 10{sup 9} to 1 × 10{sup 14} and the ion temperature with an accuracy approaching 5% for both the D(t,n){sup 4}He and D(d,n){sup 3}He reactions.

  19. Metallic ions catalysis for improving bioleaching yield of Zn and Mn from spent Zn-Mn batteries at high pulp density of 10.

    Science.gov (United States)

    Niu, Zhirui; Huang, Qifei; Wang, Jia; Yang, Yiran; Xin, Baoping; Chen, Shi

    2015-11-15

    Bioleaching of spent batteries was often conducted at pulp density of 1.0% or lower. In this work, metallic ions catalytic bioleaching was used for release Zn and Mn from spent ZMBs at 10% of pulp density. The results showed only Cu(2+) improved mobilization of Zn and Mn from the spent batteries among tested four metallic ions. When Cu(2+) content increased from 0 to 0.8 g/L, the maximum release efficiency elevated from 47.7% to 62.5% for Zn and from 30.9% to 62.4% for Mn, respectively. The Cu(2+) catalysis boosted bioleaching of resistant hetaerolite through forming a possible intermediate CuMn2O4 which was subject to be attacked by Fe(3+) based on a cycle of Fe(3+)/Fe(2+). However, poor growth of cells, formation of KFe3(SO4)2(OH)6 and its possible blockage between cells and energy matters destroyed the cycle of Fe(3+)/Fe(2+), stopping bioleaching of hetaerolite. The chemical reaction controlled model fitted best for describing Cu(2+) catalytic bioleaching of spent ZMBs. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Vitamin C, added after irradiation, reduces the mutant yield and alters the spectrum of CD59- mutations in AL cells irradiated with high LET carbon ions

    International Nuclear Information System (INIS)

    Ueno, A.M.; Vannais, D.B.; Lenarczyk, M.; Waldren, C.A.

    2003-01-01

    Miazaki, Watanabe, Kumagai and their colleagues reported that induction of HPRT - mutants by X-rays in cultured human cells was prevented by vitamin C (ascorbate) added 30 minutes after irradiation. They provided data that mutation extinction was due to neutralization by vitamin C of radiation-induced long-lived mutagenic radicals (LLR) with half-lives of several hours. We find that post-irradiation treatment with vitamin C reduces, but does not eliminate, the induction of CD59 - mutants in human-hamster hybrid A L cells exposed to high-LET carbon ions (LET of 100 keV/μm). The lethality of the carbon ions was not altered by vitamin C. Preliminary experiments indicate that post-radiation addition of vitamin C also changes the quality of CD59 - mutations induced by the carbon beam. The change in spectrum is seen as a reduction in prevalence of small mutations (not detectable by PCR) and of mutants displaying transmissible genomic instability (TGI) measured by chromosome translocation frequencies. Our results confirm the essential effect of vitamin C on X-ray induced mutation and suggest a role for LLR in genomic instability. (author)

  1. Solar cycle variation of interstellar neutral He, Ne, O density and pick-up ions along the Earth's orbit

    OpenAIRE

    Sokół, Justyna M.; Bzowski, Maciej; Kubiak, Marzena A.; Möbius, Eberhard

    2016-01-01

    We simulated the modulation of the interstellar neutral (ISN) He, Ne, and O density and pick-up ion (PUI) production rate and count rate along the Earth's orbit over the solar cycle from 2002 to 2013 to verify if solar cycle-related effects may modify the inferred ecliptic longitude of the ISN inflow direction. We adopted the classical PUI model with isotropic distribution function and adiabatic cooling, modified by time- and heliolatitude-dependent ionization rates and non-zero injection spe...

  2. Lateral variations of radiobiological properties of therapeutic fields of 1H, 4He, 12C and 16O ions studied with Geant4 and microdosimetric kinetic model

    Science.gov (United States)

    Dewey, Sophie; Burigo, Lucas; Pshenichnov, Igor; Mishustin, Igor; Bleicher, Marcus

    2017-07-01

    As known, in cancer therapy with ion beams the relative biological effectiveness (RBE) of ions changes in the course of their propagation in tissues. Such changes are caused not only by increasing the linear energy transfer (LET) of beam particles with the penetration depth towards the Bragg peak, but also by nuclear reactions induced by beam nuclei leading to the production of various secondary particles. Although the changes of RBE along the beam axis have been studied quite well, much less attention has been paid to the evolution of RBE in the transverse direction, perpendicular to the beam axis. In order to fill this gap, we simulated radiation fields of 1H, 4He, 12C and 16O nuclei of 20 mm in diameter by means of a Geant4-based Monte Carlo model for heavy-ion therapy connected with the modified microdosimetric kinetic model to describe the response of normal ((α/β)_x-rays=3.8 Gy) and early-responding ((α/β)_x-rays=10 Gy) tissues. Depth and radial distributions of saturation-corrected dose-mean lineal energy, RBE and RBE-weighted dose are investigated for passive beam shaping and active beam scanning. The field of 4He has a small lateral spread as compared with 1H field, and it is characterised by a modest lateral variation of RBE suggesting the use of fixed RBE values across the field transverse cross section at each depth. Reduced uncertainties of RBE on the boundary of a 4He treatment field can be advantageous in a specific case of an organ at risk located in lateral proximity to the target volume. It is found that the lateral distributions of RBE calculated for 12C and 16O fields demonstrate fast variations in the radial direction due to changes of dose and composition of secondary fragments in the field penumbra. Nevertheless, the radiation fields of all four projectiles at radii larger than 20 mm can be characterized by a common RBE value defined by tissue radiosensitivity. These findings can help, in particular, in accessing the transverse

  3. Screening of Mutation High-Yielding Biocontrol Bacterium BJ1 by Ion Beam Irradiation and Effect of Controlling Fusarium oxysporum cucunerinum Disease

    International Nuclear Information System (INIS)

    Ma Shuang; Dong Xicun; Li Wenjian; Wang Jufang; Yu Lixia; Liu Jing

    2010-01-01

    BJ1 of Bacillus subtilis is an important biocontrol factor in control of fungus disease. In order to improve the antagonistic ability of the strain,and obtain high-efficiency strains, 12 C 6+ of different doses and linear energy transfer (LET) was used to irradiate the biocontrol bacterium BJ1. The optimum dose and LET of ion beam irradiation for the BJ1 are 200-400 Gy and 60 keV/μm,respectively. The antagonistic ability is increased by 2%-21%. The control effect of mutation to Fusarium oxysporum f. sp. cucunerinum is increased by 17.48% over that of BJ1, and mutation also has better plant growth-promoting effect. (authors)

  4. Yield And Transverse Momentum Of Relativistic Hydrogen Isotopes In Photonuclear Spallation Of 32S Ions At 200A GeV

    International Nuclear Information System (INIS)

    Abdelsalam, A.; Kamel, S.; Abdel-Waged, Kh.; Fashed, N.

    2005-01-01

    Production of multi-hydrogen (mH) isotopes in the spallation of 200A GeV sulphur projectile using nuclear emulsion is reported. Yield of mH isotopes is studied and compared with that of the lowest energy (3.7A GeV) data. The two-source emission picture is used to describe the transverse momentum (P T ) distribution of mH isotopes (with and without the effect of 32 S (γ,p) 31 P channel). The Rayleigh type P T -distribution seems to be in agreement with the corresponding experimental data. The contributions of low and high temperature emission sources show a dependence on the photonuclear processes. (author)

  5. Mass yields in the reaction 235U(nsub(th),f) as a function of the kinetic energy and ion charge of the fission products

    International Nuclear Information System (INIS)

    Wohlfarth, H.

    1977-01-01

    In this paper measurements of mass- and ioncharge distributions of the lower mass 235 U(nsub(th),f)-fission products, performed with the 'Lohengrin' recoil spectrometer of the Institut Lane-Langevin at Grenoble, are reported. The uranium targets used led to an energy loss of the fission fragments of only 1 to 2 MeV, so their energy was well defined. The mass abundance have been measured for the following fragment energies: E = 83.6, 88.5, 93.4, 98.3, 103.1, 108.0, 112.0 MeV. The energy integrated mass distributions were compared with recent data collections of fission yields. For nearly all masses the abundancies agree well within the limits of error. So these maesurements can be used as an independent source of data. (orig./RW) [de

  6. Application of ion implantation in stevia breeding

    International Nuclear Information System (INIS)

    Wang Cailian; Chen Qiufang; Jin Wei; Lu Ting; Shu Shizhen

    1999-08-01

    Dry seed of stevia were implanted with 60-100 keV nitrogen ion and 75 keV carbon ion of various doses, and the effects of the composition and yield of stevioside were studied. The results showed that ion beam could induce variation in total stevioside yield and the composition of the plant. The best treatment was 75 keV nitrogen ion with 5 x 10 14 N + /cm 2 , the stevioside yield and Rebaudioside A (R-A) content were increased by 4.74% and 14.08% respectively. The effects induced by implantation of carbon ion were higher than those induced by implantation of nitrogen ion. Effects of Feng 1 x Ri Yuan and Ri Yuan x Feng 2 are higher than those of Ji Ning and Feng 2 . Seven mutation lines were selected from the mutation progenies. The stevioside composition of these lines were previously improved. The results suggest a potential application of ion implantation in stevia breeding

  7. A plant wide aqueous phase chemistry model describing pH variations and ion speciation/pairing in wastewater treatment process models

    DEFF Research Database (Denmark)

    Flores-Alsina, X.; Mbamba, C. Kazadi; Solon, K.

    cationic/anionic loads. In this way, the general applicability/flexibility of the proposed approach is demonstrated by implementing the aqueous phase chemistry module in some of the most frequently used WWTP process simulation models. Finally, it is shown how traditional wastewater modelling studies can......, require a major, but unavoidable, additional degree of complexity when representing cationic/anionic behaviour in Activated Sludge (AS)/Anaerobic Digestion (AD) systems (Ikumi et al., 2014). In this paper, a plant-wide aqueous phase chemistry module describing pH variations plus ion speciation...... of Ordinary Differential Equations (ODEs) in order to reduce the overall stiffness of the system, thereby enhancing simulation speed. Additionally, a multi-dimensional version of the Newton-Raphson algorithm is applied to handle the existing multiple algebraic inter-dependencies (Solon et al., 2015...

  8. A plant-wide aqueous phase chemistry module describing pH variations and ion speciation/pairing in wastewater treatment process models

    DEFF Research Database (Denmark)

    Flores Alsina, Xavier; Kazadi Mbamba, Christian; Solon, Kimberly

    2015-01-01

    at different cationic/anionic loads. In this way, the general applicability/flexibility of the proposed approach is demonstrated, by implementing the aqueous phase chemistry module in some of the most frequently used WWTP process simulation models. Finally, it is shown how traditional wastewater modelling......, but unavoidable, additional degree of complexity when representing cationic/anionic behaviour in Activated Sludge (AS)/Anaerobic Digestion (AD) systems. In this paper, a plant-wide aqueous phase chemistry module describing pH variations plus ion speciation/pairing is presented and interfaced with industry......) in order to reduce the overall stiffness of the system, thereby enhancing simulation speed. Additionally, a multi-dimensional version of the Newton-Raphson algorithm is applied to handle the existing multiple algebraic inter-dependencies. The latter is reinforced with the Simulated Annealing method...

  9. Temporal and Spatial Variations in Precipitation, Streamflow, Suspended-Sediment Loads and Yields, and Land-Condition Trend Analysis at the U.S. Army Pinon Canyon Maneuver Site, Las Animas County, Colorado, 1983 through 2007

    Science.gov (United States)

    Stevens, M.R.; Dupree, J.; Kuzmiak, J.M.

    2008-01-01

    In 2007, the U.S. Geological Survey, in cooperation with the U.S. Department of the Army, began an assessment of the spatial and temporal variations in precipitation, streamflow, suspended-sediment loads and yields, changes in land condition, effects of the tributaries on the Purgatoire River and the possible relation of effects from military training to hydrology and land conditions that have occurred at Pinon Canyon Maneuver Site (PCMS) from 1983 through 2007. Data were collected for precipitation (19 stations) and streamflow and sediment load (5 tributary and 2 main-stem Purgatoire River stations) during 1983 through 2007 for various time periods. The five tributary stations were Van Bremer Arroyo near Model, Taylor Arroyo below Rock Crossing, Lockwood Canyon Creek near Thatcher, Red Rock Canyon Creek at the mouth, and Bent Canyon Creek at the mouth. In addition, data were collected at two Purgatoire River stations: Purgatoire River near Thatcher and Purgatoire River at Rock Crossing.

  10. Event-by-event fluctuations of the particle yield ratios in heavy-ion collisions at 20 - 158 AGeV

    Energy Technology Data Exchange (ETDEWEB)

    Kresan, Dmytro

    2010-12-22

    Non-statistical event-by-event fluctuations are considered as an important signal for the critical endpoint of the QCD phase diagram. Event-by-event fluctuations of different observables are thus investigated in detail in current experiments but are also an important observable to be studied at the future CBM experiment at FAIR. In this work we present the energy and centrality dependence of event-by-event fluctuations of particle yield ratios measured by the NA49 experiment in Pb+Pb collisions at 20-158 AGeV. Systematic studies of the influence of the dE/dx resolution on the particle identification and the centrality bin size were performed. Results can be compared to event-by-event fluctuations measured by NA49 for different observables such as or the mean charged particle multiplicity. Main results of these studies are an increase of absolute value of the dynamical particle ratio fluctuations with decreasing centrality for all considered ratios, saturation of the K/{pi} and K/p ratio fluctuations for peripheral Pb + Pb collisions at 158A GeV and scaling of the energy and centrality dependences of the p/{pi} ratio fluctuations with N{sub p}N{sub {pi}}. The measured energy and centrality dependences of the K/{pi} and K/p ratio fluctuations scale with N{sub K} in a different way. The saturation of the mentioned ratios fluctuations was attributed to the development of pronounced spike at zero in the eventwise ratio distributions, which, as was shown by Monte Carlo simulations, influence the measured fluctuations in the very peripheral Pb + Pb collisions at 158A GeV. In future, the CBM experiment at FAIR will investigate the intermediate region of the QCD phase diagram in great detail searching for the first order phase transition line and the expected critical endpoint. It is therefore important to closely investigate its sensitivity towards particle ratio fluctuations in Au+Au collisions at 10-45 AGeV beam energy. Detailed simulation studies are

  11. Variation in emission and energy recovery concerning incident angle in a scheme recovering high energy ions by secondary electrons

    International Nuclear Information System (INIS)

    Wada, Takayuki; Konno, Shota; Nakamoto, Satoshi; Takeno, Hiromasa; Furuyama, Yuichi; Taniike, Akira

    2016-01-01

    As an energy recovery device for fast protons produced in D- 3 He nuclear fusion, secondary electron (SE) direct energy converter (SEDEC) was proposed in addition to traveling wave direct energy converter (TWDEC). Some protons passing through a TWDEC come into an SEDEC, where protons penetrate to a number of foil electrodes and emitted SEs are recovered. Following to a development of SE orbit control by magnetic field, dependence on incident angle of protons was examined to optimize structure of SEDEC. Based on a theoretical expectation, experiments were performed by changing incident angle of protons and variation in emission and energy recovery were measured. Both emission and energy recovery increased as the angle increased, and differences with theoretical expectation are discussed. (author)

  12. Convenient and high-yielding strategy for preparing nano-ZnMn_2O_4 as anode material in lithium-ion batteries

    International Nuclear Information System (INIS)

    Zhang, Tong; Gao, Yu; Yue, Huijuan; Qiu, Hailong; Guo, Zhendong; Wei, Yingjin; Wang, Chunzhong; Chen, Gang; Zhang, Dong

    2016-01-01

    Graphical abstract: A convenient combustion assist coprecipitation approach to synthesis nano-ZnMn2O4 anode material with excellent electrochemical performance. - Highlights: • ZnMn_2O_4 material has been gained from a novel combustion approach. • The ZnMn_2O_4 generated at 800 °C exhibits the best electrochemical performance. • This convenient method enables scale-up production of transition metal oxides. - Abstract: Time and energy saving synthesis method is crucial to the scale up applications of energy conversion and storage materials. In this report, we demonstrate a convenient and novel approach to fabricate the highly crystalline ZnMn_2O_4 nanoparticles as anode materials for Li rechargeable batteries. Pure phase ZnMn_2O_4 samples can be feasibly obtained under different calcination temperature from the precursor via combustion assisted coprecipitation method. Various techniques are used to characterize the structure and morphology of the products. Sample gained at 800 °C exhibits the best electrochemical property for lithium ion batteries. A reversible specific capacity of 716 mAh g"−"1 can be retained under a current density of 100 mA g"−"1 after 90 circles. Even the current density elevated up to 1000 mA g"−"1, the reversible capacity of the material still can be kept as high as 500 mAh g"−"1 after 1200 cycles. The outstanding performance compared to the other samples benefits from its good crystallinity and uniform dispersion with appropriate particle size.

  13. Nitrogen Ion Form and Spatio-temporal Variation in Root Distribution Mediate Nitrogen Effects on Lifespan of Ectomycorrhizal Roots

    Science.gov (United States)

    Kou, L.; McCormack, M. L.; Chen, W.; Guo, D.; Wang, H.; Li, S.; Gao, W.; Yang, H.

    2017-12-01

    Background and Aims Absorptive roots active in soil resource uptake are often intimately associated with mycorrhizal fungi, yet it remains unclear how nitrogen (N) loading affects lifespan of absorptive roots associating with ectomycorrhizal (ECM) fungi. Methods Through a three-year minirhizotron experiment, we investigated the responses of ECM lifespan to different rates of N addition and examined the roles of N ion form, rooting depth, seasonal root cohort, and ECM morphotype in mediating the N effects on ECM lifespan in a slash pine (Pinus elliottii) forest in subtropical China. Results High rates of NH4Cl significantly decreased foliar P concentrations and increased foliar N: P ratios, and mean ECM lifespan was negatively correlated to foliar P concentration. N additions generally increased the lifespan of most ectomycorrhizas, but the specific differences were context dependent. N rates and forms exerted significant positive effects on ECM lifespan with stronger effects occurring at high N rates and under ammonium N addition. N additions extended lifespan of ectomycorrhizas in shallower soil and born in spring and autumn, but shortened lifespan of ectomycorrhizas in deeper soil and born in summer and winter. N additions reduced lifespan of dichotomous ectomycorrhizas, but increased lifespan of coralloid ectomycorrhizas. Conclusions The increased ECM lifespan in response to N additions may primarily be driven by the persistent and aggravated P limitation to plants. Our findings highlight the importance of environmental contexts in controlling ECM lifespan and the need to consider potential differences among mycorrhizal morphotypes when studying N—lifespan relationships of absorptive roots in the context of N deposition.

  14. A plant-wide aqueous phase chemistry module describing pH variations and ion speciation/pairing in wastewater treatment process models.

    Science.gov (United States)

    Flores-Alsina, Xavier; Kazadi Mbamba, Christian; Solon, Kimberly; Vrecko, Darko; Tait, Stephan; Batstone, Damien J; Jeppsson, Ulf; Gernaey, Krist V

    2015-11-15

    There is a growing interest within the Wastewater Treatment Plant (WWTP) modelling community to correctly describe physico-chemical processes after many years of mainly focusing on biokinetics. Indeed, future modelling needs, such as a plant-wide phosphorus (P) description, require a major, but unavoidable, additional degree of complexity when representing cationic/anionic behaviour in Activated Sludge (AS)/Anaerobic Digestion (AD) systems. In this paper, a plant-wide aqueous phase chemistry module describing pH variations plus ion speciation/pairing is presented and interfaced with industry standard models. The module accounts for extensive consideration of non-ideality, including ion activities instead of molar concentrations and complex ion pairing. The general equilibria are formulated as a set of Differential Algebraic Equations (DAEs) instead of Ordinary Differential Equations (ODEs) in order to reduce the overall stiffness of the system, thereby enhancing simulation speed. Additionally, a multi-dimensional version of the Newton-Raphson algorithm is applied to handle the existing multiple algebraic inter-dependencies. The latter is reinforced with the Simulated Annealing method to increase the robustness of the solver making the system not so dependent of the initial conditions. Simulation results show pH predictions when describing Biological Nutrient Removal (BNR) by the activated sludge models (ASM) 1, 2d and 3 comparing the performance of a nitrogen removal (WWTP1) and a combined nitrogen and phosphorus removal (WWTP2) treatment plant configuration under different anaerobic/anoxic/aerobic conditions. The same framework is implemented in the Benchmark Simulation Model No. 2 (BSM2) version of the Anaerobic Digestion Model No. 1 (ADM1) (WWTP3) as well, predicting pH values at different cationic/anionic loads. In this way, the general applicability/flexibility of the proposed approach is demonstrated, by implementing the aqueous phase chemistry module in some

  15. Ajuste do rendimento para a variação do estande em experimentos de melhoramento genético do feijão Adjustment of the yield for the stand variation in common bean genetic breeding experiments

    Directory of Open Access Journals (Sweden)

    Clause Fátima de Brum Piana

    2007-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o ajuste do rendimento pela variação do estande em experimentos de feijão e propor procedimento para ajustamento por análise de co-variação. Utilizaram-se dados de 33 ambientes do Ensaio Estadual de Feijão do Rio Grande do Sul. Realizaram-se as análises de variação e de co-variação de rendimento e de estande em cada ambiente. Foram considerados quatro modelos de ajustamento alternativos: sem ajuste para a variação do estande; com ajuste para o estande médio geral; com ajuste para os estandes médios dos genótipos; e com ajuste para os estandes médios dos grupos de genótipos. Em 70% dos ambientes, ocorreu efeito linear ou quadrático significativo de estande sobre rendimento e em 85% efeito significativo de genótipo sobre estande. O efeito compensatório manifestou-se com diferentes intensidades nos ambientes. O ajuste do rendimento para a variação do estande, considerando o efeito de genótipos sobre o estande, é importante em ensaios de melhoramento do feijão. É necessário o registro de informações que permitam discriminar a origem da variação do estande.The objective of this work was to evaluate the adjustment of the yield for the stand in common bean experiments and to propose a procedure for the adjustment through covariance analysis. Data from 33 environments of the Common Bean Assay of Rio Grande do Sul State, Brazil, were used. Variance and covariance analyses of yield and stand were proceeded for each environment. Four alternative models were considered: without adjustment for stand; with adjustment for the average stand; with adjustment for the genotypes average stand; and with adjustment for the groups of genotypes average stand. Significant linear or quadratic effects of stand on yield occurred in 70% of the environments and of genotype on stand in 85%. The compensatory effect was manifested with different intensities in the environments. The adjustment of the yield

  16. Variation in one residue associated with the metal ion-dependent adhesion site regulates αIIbβ3 integrin ligand binding affinity.

    Directory of Open Access Journals (Sweden)

    Joel Raborn

    Full Text Available The Asp of the RGD motif of the ligand coordinates with the β I domain metal ion dependent adhesion site (MIDAS divalent cation, emphasizing the importance of the MIDAS in ligand binding. There appears to be two distinct groups of integrins that differ in their ligand binding affinity and adhesion ability. These differences may be due to a specific residue associated with the MIDAS, particularly the β3 residue Ala(252 and corresponding Ala in the β1 integrin compared to the analogous Asp residue in the β2 and β7 integrins. Interestingly, mutations in the adjacent to MIDAS (ADMIDAS of integrins α4β7 and αLβ2 increased the binding and adhesion abilities compared to the wild-type, while the same mutations in the α2β1, α5β1, αVβ3, and αIIbβ3 integrins demonstrated decreased ligand binding and adhesion. We introduced a mutation in the αIIbβ3 to convert this MIDAS associated Ala(252 to Asp. By combination of this mutant with mutations of one or two ADMIDAS residues, we studied the effects of this residue on ligand binding and adhesion. Then, we performed molecular dynamics simulations on the wild-type and mutant αIIbβ3 integrin β I domains, and investigated the dynamics of metal ion binding sites in different integrin-RGD complexes. We found that the tendency of calculated binding free energies was in excellent agreement with the experimental results, suggesting that the variation in this MIDAS associated residue accounts for the differences in ligand binding and adhesion among different integrins, and it accounts for the conflicting results of ADMIDAS mutations within different integrins. This study sheds more light on the role of the MIDAS associated residue pertaining to ligand binding and adhesion and suggests that this residue may play a pivotal role in integrin-mediated cell rolling and firm adhesion.

  17. One year online measurements of water-soluble ions at the industrially polluted town of Nanjing, China: Sources, seasonal and diurnal variations.

    Science.gov (United States)

    Wang, Honglei; An, Junlin; Cheng, Mengtian; Shen, Lijuan; Zhu, Bin; Li, Yi; Wang, Yuesi; Duan, Qing; Sullivan, Amy; Xia, Li

    2016-04-01

    Half-hourly mass concentrations water-soluble ions (WSIs) and PM2.5 were measured online a Rapid Collector of Fine Particles and Ion Chromatography system (RCFP-IC) and FH62C14 Continuous Particulate Monitor in Nanjing from October 18, 2013 to November 17, 2014. The WSIs concentration ranged from 7.07 to 333.42 μg m(-3) with an annual mean of 76.32 μg m(-3). The WSIs ranked in the order of SO4(2-) > NH4(+) > NO3(-) > Cl(-) > NO2(-) > K(+) > Ca(2+) > Na(+) > Mg(2+). The PM2.5 concentration ranged from 4.00 to 400 μg m(-3) with an annual mean of 83.58 μg m(-3). The concentrations of WSIs varied in the order of winter (115.77 μg m(-3)) > spring (76.10 μg m(-3)) > autumn (63.72 μg m(-3)) > summer (59.75 μg m(-3)), with the highest level in January (123.99 μg m(-3)) and lowest level in August (43.73 μg m(-3)). Different WSIs had distinct diurnal variations. The source analysis of the WSIs in the PCA/APCS mode illustrated that the sources consisted of secondary aerosol, coal combustion, mineral dust, biomass burning, traffic emissions and sea salt. In addition, there were seasonal variations amongst the various sources. The haze formation mechanism was different in summer and winter. The winter was dominated by NH4NO3 (18.56%), (NH4)2SO4 (28.63%), NH4(+) (11.27%), SO4(2-) (18.35%) and NO3(-) (13.13%), and by NH3 (25.93%), (NH4)2SO4 (13.37%), SO4(2-) (15.74%) and NO3(-) (9.97%) in summer. Consequently, the proportions of HCl, HNO3, NH4(+), SO4(2-) and NO3(-) were much larger during haze episodes in winter, while it was dominated by NH4NO3, NH4(+), (NH4)2SO4, SO4(2-) and NO3(-) during summer haze episodes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Effects of application boron on yields, yield component and oil ...

    African Journals Online (AJOL)

    The study was conducted to investigate the effects of five boron (B) doses; 0, 2.5, 5.0, 7.5 and 10.0 kg B ha-1 in B-deficient calcareous soils on yield and some yield components of four sunflower genotypes. Genotypes have shown variations with respect to their responses to B applications. AS-615 and Coban had the ...

  19. Diurnal variations of Titan

    Science.gov (United States)

    Cui, J.; Galand, M.; Yelle, R. V.; Vuitton, V.; Wahlund, J.-E.; Lavvas, P. P.; Mueller-Wodarg, I. C. F.; Kasprzak, W. T.; Waite, J. H.

    2009-04-01

    We present our analysis of the diurnal variations of Titan's ionosphere (between 1,000 and 1,400 km) based on a sample of Ion Neutral Mass Spectrometer (INMS) measurements in the Open Source Ion (OSI) mode obtained from 8 close encounters of the Cassini spacecraft with Titan. Though there is an overall ion depletion well beyond the terminator, the ion content on Titan's nightside is still appreciable, with a density plateau of ~700 cm-3 below ~1,300 km. Such a plateau is associated with the combination of distinct diurnal variations of light and heavy ions. Light ions (e.g. CH5+, HCNH+, C2H5+) show strong diurnal variation, with clear bite-outs in their nightside distributions. In contrast, heavy ions (e.g. c-C3H3+, C2H3CNH+, C6H7+) present modest diurnal variation, with significant densities observed on the nightside. We propose that the distinctions between light and heavy ions are associated with their different chemical loss pathways, with the former primarily through "fast" ion-neutral chemistry and the latter through "slow" electron dissociative recombination. The INMS data suggest day-to-night transport as an important source of ions on Titan's nightside, to be distinguished from the conventional scenario of auroral ionization by magnetospheric particles as the only ionizing source on the nightside. This is supported by the strong correlation between the observed night-to-day ion density ratios and the associated ion lifetimes. We construct a time-dependent ion chemistry model to investigate the effects of day-to-night transport on the ionospheric structures of Titan. The predicted diurnal variation has similar general characteristics to those observed, with some apparent discrepancies which could be reconciled by imposing fast horizontal thermal winds in Titan's upper atmosphere.

  20. On the design and implementation of a wafer yield editor

    NARCIS (Netherlands)

    Pineda de Gyvez, J.; Jess, J.A.G.

    1989-01-01

    An interactive environment is presented for the analysis of yield information required on modern integrated circuit manufacturing lines. The system estimates wafer yields and wafer-yield variations, quantifies regional yield variations within wafers, identifies clusters in wafers and/or in lots, and

  1. Fluence-dependent sputtering yield of micro-architectured materials

    Energy Technology Data Exchange (ETDEWEB)

    Matthes, Christopher S.R.; Ghoniem, Nasr M., E-mail: ghoniem@ucla.edu; Li, Gary Z.; Matlock, Taylor S.; Goebel, Dan M.; Dodson, Chris A.; Wirz, Richard E.

    2017-06-15

    Highlights: • Sputtering yield is shown to be transient and heavily dependent on surface architecture. • Fabricated nano- and Microstructures cause geometric re-trapping of sputtered material, which leads to a self-healing mechanism. • Initially, the sputtering yield of micro-architectured Mo is approximately 1/2 the value as that of a planar surface. • The study demonstrates that the sputtering yield is a dynamic property, dependent on the surface structure of a material. • A developed phenomenological model mathematically describes the transient behavior of the sputtering yield as a function of plasma fluence. - Abstract: We present an experimental examination of the relationship between the surface morphology of Mo and its instantaneous sputtering rate as function of low-energy plasma ion fluence. We quantify the dynamic evolution of nano/micro features of surfaces with built-in architecture, and the corresponding variation in the sputtering yield. Ballistic deposition of sputtered atoms as a result of geometric re-trapping is observed, and re-growth of surface layers is confirmed. This provides a self-healing mechanism of micro-architectured surfaces during plasma exposure. A variety of material characterization techniques are used to show that the sputtering yield is not a fundamental property, but that it is quantitatively related to the initial surface architecture and to its subsequent evolution. The sputtering yield of textured molybdenum samples exposed to 300 eV Ar plasma is roughly 1/2 of the corresponding value for flat samples, and increases with ion fluence. Mo samples exhibited a sputtering yield initially as low as 0.22 ± 5%, converging to 0.4 ± 5% at high fluence. The sputtering yield exhibits a transient behavior as function of the integrated ion fluence, reaching a steady-state value that is independent of initial surface conditions. A phenomenological model is proposed to explain the observed transient sputtering phenomenon, and to

  2. Breeding for Grass Seed Yield

    DEFF Research Database (Denmark)

    Boelt, Birte; Studer, Bruno

    2010-01-01

    Seed yield is a trait of major interest for many fodder and amenity grass species and has received increasing attention since seed multiplication is economically relevant for novel grass cultivars to compete in the commercial market. Although seed yield is a complex trait and affected...... by agricultural practices as well as environmental factors, traits related to seed production reveal considerable genetic variation, prerequisite for improvement by direct or indirect selection. This chapter first reports on the biological and physiological basics of the grass reproduction system, then highlights...... important aspects and components affecting the seed yield potential and the agronomic and environmental aspects affecting the utilization and realization of the seed yield potential. Finally, it discusses the potential of plant breeding to sustainably improve total seed yield in fodder and amenity grasses....

  3. Characterization of ion beam induced nanostructures

    International Nuclear Information System (INIS)

    Ghatak, J.; Satpati, B.; Umananda, M.; Kabiraj, D.; Som, T.; Dev, B.N.; Akimoto, K.; Ito, K.; Emoto, T.; Satyam, P.V.

    2006-01-01

    Tailoring of nanostructures with energetic ion beams has become an active area of research leading to the fundamental understanding of ion-solid interactions at nanoscale regime and with possible applications in the near future. Rutherford backscattering spectrometry (RBS), high resolution transmission electron microscopy (HRTEM) and asymmetric X-ray Bragg-rocking curve experimental methods have been used to characterize ion-induced effects in nanostructures. The possibility of surface and sub-surface/interface alloying at nano-scale regime, ion-beam induced embedding, crater formation, sputtering yield variations for systems with isolated nanoislands, semi-continuous and continuous films of noble metals (Au, Ag) deposited on single crystalline silicon will be reviewed. MeV-ion induced changes in specified Au-nanoislands on silicon substrate are tracked as a function of ion fluence using ex situ TEM. Strain induced in the bulk silicon substrate surface due to 1.5 MeV Au 2+ and C 2+ ion beam irradiation is determined by using HRTEM and asymmetric Bragg X-ray rocking curve methods. Preliminary results on 1.5 MeV Au 2+ ion-induced effects in nanoislands of Co deposited on silicon substrate will be discussed

  4. Probing thin over layers with variable energy/cluster ion beams

    International Nuclear Information System (INIS)

    Spool, A.; White, R.

    2006-01-01

    A series of carbon-coated magnetic recording disks proved ideal for exploring sampling depth and ion formation trends as a function of variations in energy and cluster size (Au x ) of the primary ion beam, and variations in over coat thickness and type. Ion yield from the underlying metal layer increased with increasing energy and decreasing cluster size of the primary ions. The yields varied nearly linearly with over layer thickness. In contrast, M x Cs y depth profiles were unaffected by changes in the primary ion. The samples were fortuitously dosed with dinonyl phthalate, allowing a study similar to prior GSIMS work [I.S. Gilmore, M.P. Seah, J.E. Johnstone, in: A. Benninghoven, P. Bertrand, H.-N. Migeon, H.W. Werner (Eds.), Proceedings of the 12th International Conference on SIMS, Elsevier, Brussels, 2000, p. 801]. Ions prominent in the EI mass spectrum, including even electron ions, were more consistently enhanced at lower energies and higher cluster sizes than the primary (M + H) + ion. The total secondary ion count was inversely proportional to the film thickness. Secondary electrons, largely originating in the buried metal layer, may be inducing organic ion formation [A.M. Spool, Surf. Interface Anal. 36 (2004) 264

  5. GDP growth and the yield curvature

    DEFF Research Database (Denmark)

    Møller, Stig Vinther

    2014-01-01

    This paper examines the forecastability of GDP growth using information from the term structure of yields. In contrast to previous studies, the paper shows that the curvature of the yield curve contributes with much more forecasting power than the slope of yield curve. The yield curvature also...... predicts bond returns, implying a common element to time-variation in expected bond returns and expected GDP growth....

  6. Energy landscapes for mobile ions in ion conducting solids

    Indian Academy of Sciences (India)

    molecular dynamics (MD) simulations yields quantitative predictions of the ion transport characteristics. As ... Solid electrolytes; bond valence analysis; ion transport in glasses. 1. .... clusters are considered to contribute only to a.c. conduc-.

  7. Expression of OsSPY and 14-3-3 genes involved in plant height variations of ion-beam-induced KDML 105 rice mutants

    Energy Technology Data Exchange (ETDEWEB)

    Phanchaisri, Boonrak [Science and Technology Research Institute, Chiang Mai University, Chiang Mai 50200 (Thailand); Molecular Biology Laboratory, Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Samsang, Nuananong [Molecular Biology Laboratory, Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, Liang Deng; Singkarat, Somsorn [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Anuntalabhochai, Somboon, E-mail: soanu.1@gmail.com [Molecular Biology Laboratory, Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2012-06-01

    The culm length of two semidwarf rice mutants (PKOS1, HyKOS1) obtained from low-energy N-ion beam bombardments of dehusked Thai jasmine rice (Oryza sativa L. cv. KDML 105) seeds showed 25.7% and 21.5% height reductions and one spindly rice mutant (TKOS4) showed 21.4% increase in comparison with that of the KDML 105 control. A cDNA-RAPD analysis identified differential gene expression in internode tissues of the rice mutants. Two genes identified from the cDNA-RAPD were OsSPY and 14-3-3, possibly associated with stem height variations of the semidwarf and spindly mutants, respectively. The OsSPY gene encoded the SPY protein which is considered to be a negative regulator of gibberellin (GA). On the other hand, the 14-3-3 encoded a signaling protein which can bind and prevent the RSG (repression of shoot growth) protein function as a transcriptional repressor of the kaurene oxidase (KO) gene in the GA biosynthetic pathway. Expression analysis of OsSPY, 14-3-3, RSG, KO, and SLR1 was confirmed in rice internode tissues during the reproductive stage of the plants by semi-quantitative RT-PCR technique. The expression analysis showed a clear increase of the levels of OsSPY transcripts in PKOS1 and HyKOS1 tissue samples compared to that of the KDML 105 and TKOS4 samples at the age of 50-60 days which were at the ages of internode elongation. The 14-3-3 expression had the highest increase in the TKOS4 samples compared to those in KDML 105, PKOS1 and HyKOS1 samples. The expression analysis of RSG and KO showed an increase in TKOS4 samples compared to that of the KDML 105 and that of the two semidwarf mutants. These results indicate that changes of OsSPY and 14-3-3 expression could affect internode elongation and cause the phenotypic changes of semidwarf and spindly rice mutants, respectively.

  8. Expression of OsSPY and 14-3-3 genes involved in plant height variations of ion-beam-induced KDML 105 rice mutants

    International Nuclear Information System (INIS)

    Phanchaisri, Boonrak; Samsang, Nuananong; Yu, Liang Deng; Singkarat, Somsorn; Anuntalabhochai, Somboon

    2012-01-01

    The culm length of two semidwarf rice mutants (PKOS1, HyKOS1) obtained from low-energy N-ion beam bombardments of dehusked Thai jasmine rice (Oryza sativa L. cv. KDML 105) seeds showed 25.7% and 21.5% height reductions and one spindly rice mutant (TKOS4) showed 21.4% increase in comparison with that of the KDML 105 control. A cDNA-RAPD analysis identified differential gene expression in internode tissues of the rice mutants. Two genes identified from the cDNA-RAPD were OsSPY and 14-3-3, possibly associated with stem height variations of the semidwarf and spindly mutants, respectively. The OsSPY gene encoded the SPY protein which is considered to be a negative regulator of gibberellin (GA). On the other hand, the 14-3-3 encoded a signaling protein which can bind and prevent the RSG (repression of shoot growth) protein function as a transcriptional repressor of the kaurene oxidase (KO) gene in the GA biosynthetic pathway. Expression analysis of OsSPY, 14-3-3, RSG, KO, and SLR1 was confirmed in rice internode tissues during the reproductive stage of the plants by semi-quantitative RT-PCR technique. The expression analysis showed a clear increase of the levels of OsSPY transcripts in PKOS1 and HyKOS1 tissue samples compared to that of the KDML 105 and TKOS4 samples at the age of 50–60 days which were at the ages of internode elongation. The 14-3-3 expression had the highest increase in the TKOS4 samples compared to those in KDML 105, PKOS1 and HyKOS1 samples. The expression analysis of RSG and KO showed an increase in TKOS4 samples compared to that of the KDML 105 and that of the two semidwarf mutants. These results indicate that changes of OsSPY and 14-3-3 expression could affect internode elongation and cause the phenotypic changes of semidwarf and spindly rice mutants, respectively.

  9. PIXE depth profiling using variation of detection angle

    International Nuclear Information System (INIS)

    Miranda, J.; Rickards, J.; Trejo-Luna, R.

    2006-01-01

    A method to apply particle induced X-ray emission (PIXE) for depth profiling, based on the variation of the X-ray detection angle, is proposed. The procedure uses X-ray yields normalized to those emitted at a particular reference angle. Application of the method to implanted samples and thin metallic films gave excellent results regarding the range of implanted ions and film thickness, respectively. However, there is no complete information about the width of the distribution of the implanted ions, emphasizing the need to develop a full mathematical algorithm to obtain the general depth profile

  10. Fission yield measurements at IGISOL

    Science.gov (United States)

    Lantz, M.; Al-Adili, A.; Gorelov, D.; Jokinen, A.; Kolhinen, V. S.; Mattera, A.; Moore, I.; Penttilä, H.; Pomp, S.; Prokofiev, A. V.; Rakopoulos, V.; Rinta-Antila, S.; Simutkin, V.; Solders, A.

    2016-06-01

    The fission product yields are an important characteristic of the fission process. In fundamental physics, knowledge of the yield distributions is needed to better understand the fission process. For nuclear energy applications good knowledge of neutroninduced fission-product yields is important for the safe and efficient operation of nuclear power plants. With the Ion Guide Isotope Separator On-Line (IGISOL) technique, products of nuclear reactions are stopped in a buffer gas and then extracted and separated by mass. Thanks to the high resolving power of the JYFLTRAP Penning trap, at University of Jyväskylä, fission products can be isobarically separated, making it possible to measure relative independent fission yields. In some cases it is even possible to resolve isomeric states from the ground state, permitting measurements of isomeric yield ratios. So far the reactions U(p,f) and Th(p,f) have been studied using the IGISOL-JYFLTRAP facility. Recently, a neutron converter target has been developed utilizing the Be(p,xn) reaction. We here present the IGISOL-technique for fission yield measurements and some of the results from the measurements on proton induced fission. We also present the development of the neutron converter target, the characterization of the neutron field and the first tests with neutron-induced fission.

  11. Fission yield measurements at IGISOL

    Directory of Open Access Journals (Sweden)

    Lantz M.

    2016-01-01

    Full Text Available The fission product yields are an important characteristic of the fission process. In fundamental physics, knowledge of the yield distributions is needed to better understand the fission process. For nuclear energy applications good knowledge of neutroninduced fission-product yields is important for the safe and efficient operation of nuclear power plants. With the Ion Guide Isotope Separator On-Line (IGISOL technique, products of nuclear reactions are stopped in a buffer gas and then extracted and separated by mass. Thanks to the high resolving power of the JYFLTRAP Penning trap, at University of Jyväskylä, fission products can be isobarically separated, making it possible to measure relative independent fission yields. In some cases it is even possible to resolve isomeric states from the ground state, permitting measurements of isomeric yield ratios. So far the reactions U(p,f and Th(p,f have been studied using the IGISOL-JYFLTRAP facility. Recently, a neutron converter target has been developed utilizing the Be(p,xn reaction. We here present the IGISOL-technique for fission yield measurements and some of the results from the measurements on proton induced fission. We also present the development of the neutron converter target, the characterization of the neutron field and the first tests with neutron-induced fission.

  12. Negative ion sources

    International Nuclear Information System (INIS)

    Ishikawa, Junzo; Takagi, Toshinori

    1983-01-01

    Negative ion sources have been originally developed at the request of tandem electrostatic accelerators, and hundreds of nA to several μA negative ion current has been obtained so far for various elements. Recently, the development of large current hydrogen negative ion sources has been demanded from the standpoint of the heating by neutral particle beam injection in nuclear fusion reactors. On the other hand, the physical properties of negative ions are interesting in the thin film formation using ions. Anyway, it is the present status that the mechanism of negative ion action has not been so fully investigated as positive ions because the history of negative ion sources is short. In this report, the many mechanisms about the generation of negative ions proposed so far are described about negative ion generating mechanism, negative ion source plasma, and negative ion generation on metal surfaces. As a result, negative ion sources are roughly divided into two schemes, plasma extraction and secondary ion extraction, and the former is further classified into the PIG ion source and its variation and Duoplasmatron and its variation; while the latter into reflecting and sputtering types. In the second half of the report, the practical negative ion sources of each scheme are described. If the mechanism of negative ion generation will be investigated more in detail and the development will be continued under the unified know-how as negative ion sources in future, the development of negative ion sources with which large current can be obtained for any element is expected. (Wakatsuki, Y.)

  13. Time and Energy Characterization of a Neutron Time of Flight Detector Using a Novel Coincidence Method for Constraining Neutron Yield, Ion Temperature and Liner Density Measurements from MagLIF Experiments

    Science.gov (United States)

    Styron, Jedediah D.

    relevant for diagnosing the plasma performance and confinement--the plasma ion temperature, the beryllium liner areal density, and the neutron yield--which significantly enhances the information that can be obtained from the Z NTOF signals. The model also clarifies the source of features that have been observed in the NTOF signs that were not well understood before. In addition, this capability and methodology can be used to re-design the source to detector lines-of-sight such that the magnitudes of the required corrections are minimized.

  14. Ion-Beam-Excited Electrostatic Ion Cyclotron Waves

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens

    1976-01-01

    Self-excited electrostatic ion cyclotron waves were observed in an ion-beam-plasma system produced in a DP-operated Q-machine. The frequency of the waves showed the theoretically predicted variation with the magnetic field.......Self-excited electrostatic ion cyclotron waves were observed in an ion-beam-plasma system produced in a DP-operated Q-machine. The frequency of the waves showed the theoretically predicted variation with the magnetic field....

  15. Decomposing global crop yield variability

    Science.gov (United States)

    Ben-Ari, Tamara; Makowski, David

    2014-11-01

    Recent food crises have highlighted the need to better understand the between-year variability of agricultural production. Although increasing future production seems necessary, the globalization of commodity markets suggests that the food system would also benefit from enhanced supplies stability through a reduction in the year-to-year variability. Here, we develop an analytical expression decomposing global crop yield interannual variability into three informative components that quantify how evenly are croplands distributed in the world, the proportion of cultivated areas allocated to regions of above or below average variability and the covariation between yields in distinct world regions. This decomposition is used to identify drivers of interannual yield variations for four major crops (i.e., maize, rice, soybean and wheat) over the period 1961-2012. We show that maize production is fairly spread but marked by one prominent region with high levels of crop yield interannual variability (which encompasses the North American corn belt in the USA, and Canada). In contrast, global rice yields have a small variability because, although spatially concentrated, much of the production is located in regions of below-average variability (i.e., South, Eastern and South Eastern Asia). Because of these contrasted land use allocations, an even cultivated land distribution across regions would reduce global maize yield variance, but increase the variance of global yield rice. Intermediate results are obtained for soybean and wheat for which croplands are mainly located in regions with close-to-average variability. At the scale of large world regions, we find that covariances of regional yields have a negligible contribution to global yield variance. The proposed decomposition could be applied at any spatial and time scales, including the yearly time step. By addressing global crop production stability (or lack thereof) our results contribute to the understanding of a key

  16. Variations in ion and neutral composition at Venus - Evidence of solar control of the formation of the predawn bulges in H/+/ and He1

    Science.gov (United States)

    Taylor, H. A., Jr.; Mayr, H.; Brinton, H.; Niemann, H.; Hartle, R.; Daniell, R. E., Jr.

    1982-01-01

    A comparison of ion and neutral composition measurements at Venus for periods of greatly different solar activity provides qualitative evidence of solar control of the day-to-night transport of light ion and neutral species. Concentrations of H(+) and He in the predawn bulge near solar maximum in November, 1979, exhibit a depletion signature correlated with a pronounced modulation in the solar F10.7 and EUV fluxes. This perturbation, not observed in the predawn region during an earlier period of relative quiet solar conditions, is interpreted as resulting from pronounced changes in solar heating and photoionization on the dayside, which in turn modulate the transport of ions and neutrals into the bulge region.

  17. Equity Volatility and Corporate Bond Yields

    OpenAIRE

    John Y. Campbell; Glen B. Taksler

    2002-01-01

    This paper explores the effect of equity volatility on corporate bond yields. Panel data for the late 1990s show that idiosyncratic firm-level volatility can explain as much cross-sectional variation in yields as can credit ratings. This finding, together with the upward trend in idiosyncratic equity volatility documented by Campbell, Lettau, Malkiel, and Xu (2001), helps to explain recent increases in corporate bond yields. The definitive version is available at www.blackwell-synergy.com.

  18. Yield Mapping in Salix; Skoerdekartering av salix

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Christoffer; Gilbertsson, Mikael; Rogstrand, Gustav; Thylen, Lars

    2004-09-01

    The most common species for energy forest production is willow. Willow is able to produce a large amount of biomass in a short period of time. Growing willow has a potential to render a good financial result for the farmer if cultivated on fields with the right conditions and plenty of water. Under the right conditions growing willow can give the farmer a net income of 3,000 SEK (about 430 USD) per hectare and year, which is something that common cereal crops cannot compete with. However, this is not the common case since willow is often grown as a substitute crop on fields where cereal crop yield is low. The aim of this study was to reveal if it is possible to measure yield variability in willow, and if it is possible to describe the reasons for yield variation both within the field but also between different fields. Yield mapping has been used in conventional farming for about a decade. The principles for yield mapping are to continuously measure the yield while registering location by the use of GPS when harvesting the field. The collected data is then used to search for spatial variations within the field, and to try to understand the reasons for this variation. Since there is currently no commercial equipment for yield mapping in willow, a yield mapping system had to be developed within this project. The new system was installed on a Claas Jaguar harvester. The principle for yield mapping on the Claas Jaguar harvester is to measure the distance between the feeding rollers. This distance is correlated to the flow through the harvester. The speed and position of the machine was registered using GPS. Knowing the working width of the harvester this information was used to calculate the yield. All collected data was stored on a PDA computer. Soil samples were also collected from the yield mapped fields. This was to be able to test yield against both physical and chemical soil parameters. The result shows that it is possible to measure spatial variations of yield in

  19. Pattern formation on Ge by low energy ion beam erosion

    International Nuclear Information System (INIS)

    Teichmann, Marc; Lorbeer, Jan; Frost, Frank; Rauschenbach, Bernd; Ziberi, Bashkim

    2013-01-01

    Modification of nanoscale surface topography is inherent to low-energy ion beam erosion processes and is one of the most important fields of nanotechnology. In this report a comprehensive study of surface smoothing and self-organized pattern formation on Ge(100) by using different noble gases ion beam erosion is presented. The investigations focus on low ion energies (⩽ 2000 eV) and include the entire range of ion incidence angles. It is found that for ions (Ne, Ar) with masses lower than the mass of the Ge target atoms, no pattern formation occurs and surface smoothing is observed for all angles of ion incidence. In contrast, for erosion with higher mass ions (Kr, Xe), ripple formation starts at incidence angles of about 65° depending on ion energy. At smaller incident angles surface smoothing occurs again. Investigations of the surface dynamics for specific ion incidence angles by changing the ion fluence over two orders of magnitude gives a clear evidence for coarsening and faceting of the surface pattern. Both observations indicate that gradient-dependent sputtering and reflection of primary ions play crucial role in the pattern evolution, just at the lowest accessible fluences. The results are discussed in relation to recently proposed redistributive or stress-induced models for pattern formation. In addition, it is argued that a large angular variation of the sputter yield and reflected primary ions can significantly contribute to pattern formation and evolution as nonlinear and non-local processes as supported by simulation of sputtering and ion reflection. (paper)

  20. Genetic variations in the dynamics of dry matter accumulation, nitrogen assimilation and translocation in new T. aestivum L. varieties. II. Nitrogen assimilation and translocation in relation to grain yield and protein content

    International Nuclear Information System (INIS)

    Nankova, M.; Kostov, K.; Penchev, E.

    1999-01-01

    The study was carried out under greenhouse and field conditions and showed considerable genotype differences between the vrs. Enola, Karat, Svilena and Pliska (T. aestivum L.) with regard to N assimilation during heading, which played an important role in grain yield formation (0.852). Grain yield depends considerably on N translocation (NT) in the period heading-full maturity (0.864) and on its part affects the intensity of N uptake in grain during grain filling-full maturity. In both experiments cv. Svilena demonstrated high NR from the leaves, which was the reason for more than 52 % of N in grain. In the field experiment cv. Svilena confirmed this tendency, the NR being highest in the 2-3 leaf stage, followed by the flag leaf and the down leaves. The intensity of N uptake in grain during grain filling-full maturity was highest in the vrs. Enola and Karat. This intensity was in strong correlation with NA during heading, and with NT in V m during heading-full maturity. It also affected to a high degree the protein content in grain, as well as grain yield. In both experiments a strong negative correlation was established between the NHI/GHI ratio, and grain yield and nitrogen assimilation during heading; a positive correlation was determined with grain NHI. Under the conditions of increasing N dressing, the vrs. Enola, Karat, and Svilena had higher N expense for formation of a production unit, 63 up to 91 % of the N being used for formation of grain with high protein content. Protein yield correlated strongly not only with protein in grain, but also with the intensity of uptake in grain during grain filling - full maturity. The highest protein yield was registered in cv. Karat. By their N expense for production of 100 kg protein, the new varieties did not differ from the standard variety Pliska. The results from the study showed a higher genetic potential of the agrochemically promising varieties Karat, Enola and Svilena than the standard variety Pliska. Refs. 10

  1. Measurements of beryllium sputtering yields at JET

    Science.gov (United States)

    Jet-Efda Contributors Stamp, M. F.; Krieger, K.; Brezinsek, S.

    2011-08-01

    The lifetime of the beryllium first wall in ITER will depend on erosion and redeposition processes. The physical sputtering yields for beryllium (both deuterium on beryllium (Be) and Be on Be) are of crucial importance since they drive the erosion process. Literature values of experimental sputtering yields show an order of magnitude variation so predictive modelling of ITER wall lifetimes has large uncertainty. We have reviewed the old beryllium yield experiments on JET and used current beryllium atomic data to produce revised beryllium sputtering yields. These experimental measurements have been compared with a simple physical sputtering model based on TRIM.SP beryllium yield data. Fair agreement is seen for beryllium yields from a clean beryllium limiter. However the yield on a beryllium divertor tile (with C/Be co-deposits) shows poor agreement at low electron temperatures indicating that the effect of the higher sputtering threshold for beryllium carbide is important.

  2. Spectral variations and energy transfer processes on both Er 3+ ion concentration and excitation densities in Yb 3+-Er 3+ codoped LaF3 materials

    International Nuclear Information System (INIS)

    Zhang Jisen; Qin Weiping; Zhao Dan; Degejihu; Zhang Jishuang; Wang Yan; Cao Chunyan

    2007-01-01

    In comparison with the up-conversion spectra of Yb 3+ -Er 3+ codopded systems reported previously, the interesting intensity changes of up-conversion luminescence between the violet, the blue, the green and the red on the both Er 3+ ion concentration and excitation density with 978 nm laser diodes as an excitation source were observed in Yb 3+ -Er 3+ codopded LaF 3 powders. In order to clarify the change mechanisms, the up-conversion spectra of LaF 3 : 10 mol% Yb 3+ , 0.5 mol% Er 3+ and LaF 3 : 10 mol% Yb 3+ , 1 mol% Er 3+ were investigated and the results indicated that the cross-relaxation processes between Er 3+ ions and the thermal population of the 2 H 11/2 level play significant roles

  3. Experimental study of the organic ion intensity distribution in the ion imaging of coated polymer fibres with S-SIMS

    International Nuclear Information System (INIS)

    Vercammen, Yannick; Moons, Nicola; Van Nuffel, Sebastiaan; Beenaerts, Linda; Van Vaeck, Luc

    2013-01-01

    Time-of-Flight Static Secondary Ion Mass Spectrometry excels in probing the molecular composition of the outer monolayer of flat samples with a lateral resolution in the sub-μm range. However, the method faces significant methodological problems in the case of non-conducting samples with high topography or surface curvature, such as fibres, yarns or fabrics. Specifically, the useful secondary ion yield in a given spot on the fibre depends on the local incidence angle, the height above the earthed sample holder, the position relative to the axis of the mass analyser and the extent of the local surface charging. This study has focused on the empiric reduction of the useful ion yield variations observed in the ion images of fibres with diameter of 25 and 100 μm. Up to now, most literature data consider the analysis of fibres positioned along or perpendicular to the projection of the projectile beam in the plane of the sample surface because these specific geometries facilitate the interpretation of the ion images. However, it has been discovered that the diagonal orientation of the fibre in the field-of-view largely reduces the ion yield variations for fibres with a small diameter (25 μm). The situation is different for fibres with a diameter of 100 μm. In that case, the ion images contain no secondary ion counts for the pixels referring to a significant part of the fibre. In particular, the resulting lack of delineation between the shadow zone in the front of the fibre and the boundary of the fibre hampers the practical use of the ion images A fourfold decrease of the extraction voltage or a 20% increase of the distance between sample holder and extraction electrode is found to improve the detection of secondary ions from the part of the fibre facing towards the impinging primary ion beam. These observations have been tentatively related to the mass analyser acceptance and its dependence on the delicate balance between conflicting effects such as field strength

  4. 6 Grain Yield

    African Journals Online (AJOL)

    create a favourable environment for rice ... developing lines adaptable to many ... have stable, not too short crop duration with ..... Analysis of variance of the effect of site and season on maturity, grain yield and plant ..... and yield components.

  5. Diurnal variations of Titan's ionosphere

    Science.gov (United States)

    Cui, J.; Galand, M.; Yelle, R. V.; Vuitton, V.; Wahlund, J.-E.; Lavvas, P. P.; Müller-Wodarg, I. C. F.; Cravens, T. E.; Kasprzak, W. T.; Waite, J. H.

    2009-06-01

    We present our analysis of the diurnal variations of Titan's ionosphere (between 1000 and 1300 km) based on a sample of Ion Neutral Mass Spectrometer (INMS) measurements in the Open Source Ion (OSI) mode obtained from eight close encounters of the Cassini spacecraft with Titan. Although there is an overall ion depletion well beyond the terminator, the ion content on Titan's nightside is still appreciable, with a density plateau of ˜700 cm-3 below ˜1300 km. Such a plateau is a combined result of significant depletion of light ions and modest depletion of heavy ones on Titan's nightside. We propose that the distinctions between the diurnal variations of light and heavy ions are associated with their different chemical loss pathways, with the former primarily through “fast” ion-neutral chemistry and the latter through “slow” electron dissociative recombination. The strong correlation between the observed night-to-day ion density ratios and the associated ion lifetimes suggests a scenario in which the ions created on Titan's dayside may survive well to the nightside. The observed asymmetry between the dawn and dusk ion density profiles also supports such an interpretation. We construct a time-dependent ion chemistry model to investigate the effect of ion survival associated with solid body rotation alone as well as superrotating horizontal winds. For long-lived ions, the predicted diurnal variations have similar general characteristics to those observed. However, for short-lived ions, the model densities on the nightside are significantly lower than the observed values. This implies that electron precipitation from Saturn's magnetosphere may be an additional and important contributor to the densities of the short-lived ions observed on Titan's nightside.

  6. Ion pair formation in the vacuum ultraviolet region of NO studied by negative ion imaging spectroscopy

    International Nuclear Information System (INIS)

    Hikosaka, Y.; Kaneyasu, T.; Shigemasa, E.

    2007-01-01

    The pair formation of positive and negative fragment ions has been studied in the vacuum ultraviolet region of NO, with negative ion imaging spectroscopy. The negative ion yield curve obtained in the photon energy region of 19-25 eV exhibits many structures which are absent from the photoabsorption spectrum in the same region. The partial yields and asymmetry parameters associated with the dissociations into individual ion pair limits have been extracted from the negative ion images observed. On the basis of these quantities, the assignments for the structures exhibited on the negative ion yield curve are given and the dynamical properties on the ion pair dissociation are discussed

  7. A simulation study of antimatter-helium ion planar channeling in silicon

    International Nuclear Information System (INIS)

    Wijesundera, Dharshana; Jayarathna, Sandun; Bellwied, Rene; Chu, Wei-Kan

    2012-01-01

    With the physical significance arising with the reports on experimental observation of antimatter-He nuclei, we have investigated a case of 2 MeV antimatter-He ion planar channeling in Si (1 0 0) in comparison with He channeling, by simulation. For a negatively charged antimatter-He nucleus, the planar potential well is centered at the atomic plane itself as opposed to the center-channel minimum for He ions; the antimatter-He ion distribution therefore tends to concentrate toward the atomic lattice planes. The antimatter-He ion flux distribution and the resulting close encounter probability are crucial in determining the probability of close encounter events including annihilation at channeling incidence. We have therefore analyzed the variation of antimatter-He ion flux distribution within the channels with respect to the angle of incidence and have thereby derived the orientation dependence of probability of close encounter events, or an antimatter-He channeling angular scan. The angular scan is inverted with a maximum yield at the perfect beam-planar alignment. The half-angle is narrower compared to He channeling, as a consequence of the narrower planar channeling potential centered at the lattice planes. The high de-channeling rate associated with the higher antimatter-He ion concentration in the proximity of lattice planes causes the maximum yield to be less prominent and to decrease rapidly with depth. The shoulder region shows strong depth dependent reduction that can be associated to near surface depth dependent ion flux variation.

  8. Emission of positive oxygen ions from ion bombardment of adsorbate-covered metal surfaces

    International Nuclear Information System (INIS)

    Kaurin, M.G.

    1989-01-01

    During ion bombardment of metal surfaces, collision cascades can result in the emission of sputtered secondary ions. Recent experiments, however, have suggested that the emission of positive ions of electronegative adsorbates can result from electronic processes rather than from processes involving elastic collisions. This dissertation presents the results of experiments studying the emission of positive oxygen ions from oxygen- and carbon-monoxide-covered transition metal surfaces during bombardment by 25-250 keV ions of neon, argon, and krypton. The systems studied may be grouped into four categories. For a nickel substrate with adsorbed oxygen, the emission of positive oxygen ions proceeds through collision cascades. For titanium and niobium with adsorbed oxygen, the emission of positive oxygen ions is proportional to the primary ion velocity, consistent with emission from electronic processes; for a given primary ion velocity, the oxygen ion yield is independent of primary ion species. For substrates of molybdenum and tungsten, the oxygen yield is proportional to primary ion velocity, but the yield also depends on the primary ion species for a given primary ion velocity in a manner that is consistent with emission resulting from electronic processes. For these two groups, except for titanium, the yields during neon ion bombardment do not extrapolate (assuming linearity with primary ion velocity) to a nonzero value at zero beam velocity. The magnitude of the oxygen ion yields from these targets is not consistent with that expected if the emission were induced by secondary electrons emitted during the ion bombardment

  9. Doppler ion program description

    International Nuclear Information System (INIS)

    Henline, P.

    1980-12-01

    The Doppler spectrometer is a conventional Czerny-Turner grating spectrometer with a 1024 channel multiple detector. Light is dispersed across the detector, and its output yields a spectrum covering approximately 200 A. The width of the spectral peak is directly proportional to the temperature of the emitting ions, and determination of the impurity ion temperature allows one to infer the plasma ion temperature. The Doppler ion software system developed at General Atomic uses a TRACOR Northern 1710-31 and an LSI-11/2. The exact configuration of Doublet III is different from TRACOR Northern systems at other facilities

  10. Time variations of magnetospheric intensities of outer zone protons, alpha particles and ions (Z greater than or equal to 2). Ph.D. Thesis

    Science.gov (United States)

    Randall, B. A.

    1973-01-01

    A comprehensive study of the temporal behavior of trapped protons, alpha particles and ions (Z 2) in outer zone of the earth's magnetosphere has been made. These observations were made by the Injun V satellite during the first 21 months of operation, August 1968 to May 1970. Rapid increases in the observed number of particles followed by slower exponential decay characterize the data. Comparisons are made with the temporal behavior of interplanetary particles of the same energy observed by Explorer 35. Increases in the trapped fluxes generally correspond to enhanced interplanetary activity. The energy spectra of protons and alpha particles at L = 3 have similar shapes when compared on an energy per charge basis while the respective polar cap spectra have similar shape on an energy per nucleon basis. Apparent inward trans-L motion of energetic protons is observed. These particles are diffused inward by a process involving fluctuating electric fields. The loss of trapped low altitude protons, alpha particles and ions (Z 2) is controlled by coulombic energy loss in the atmosphere.

  11. Variations in the microstructure of nickel-based alloy coatings with the metalloids boron and silicon as a function of deposition parameters in a dual beam ion system

    International Nuclear Information System (INIS)

    Panitz, J.K.G.

    1986-01-01

    We have deposited coatings using a dual beam ion source system with two different targets as sputtering sources; (i) a predominantly amorphous Ni/sub 63.5/Cr/sub 12.3/Fe/sub 3.5/Si/sub 7.9/B/sub 12.8/ foil and (ii) a crystalline Ni/sub 55.3/Cr/sub 16.9/Si/sub 7.2/B/sub 21.6/ slab from a casting. Amorphous coatings were produced by the foil for all conditions studied. The coatings that were deposited from the slab target that were less than 400 nm in thickness which were deposited at rates from 8--50 nm/min appeared to be amorphous. The thicker (>400 nm) coatings and the extremely low deposition rate (2 nm/min) coatings produced by the slab comprised both partially polycrystalline and amorphous material. All of the coatings studied exhibited inferior wear and erosion resistance properties compared to iron-based amorphous metal coatings containing Ti, C, or N, which have been studied by other groups. However, the corrosion resistance to 4 N HCl is good, ranging from less than 0.01 to 0.22 mm/yr as a function of deposition rate, concurrent ion bombardment conditions, and coating thickness

  12. Inheritance of grain yield and its correlation with yield components in ...

    African Journals Online (AJOL)

    SAM

    2014-03-19

    Mar 19, 2014 ... average yield of wheat in China is 4.75 t ha-1, which is low compared to other .... Analysis of variance for combining ability for grain yield plant-1. Source of variation ..... Hayman BI (1954). The theory and analysis of diallel crosses. .... Analysis and prospect of China wheat market in 2011. Food and Oil.

  13. Yield stress fluids slowly yield to analysis

    NARCIS (Netherlands)

    Bonn, D.; Denn, M.M.

    2009-01-01

    We are surrounded in everyday life by yield stress fluids: materials that behave as solids under small stresses but flow like liquids beyond a critical stress. For example, paint must flow under the brush, but remain fixed in a vertical film despite the force of gravity. Food products (such as

  14. Ion yields in UV-MALDI mass spectrometry as a function of excitation laser wavelength and optical and physico-chemical properties of classical and halogen-substituted MALDI matrixes.

    Science.gov (United States)

    Soltwisch, Jens; Jaskolla, Thorsten W; Hillenkamp, Franz; Karas, Michael; Dreisewerd, Klaus

    2012-08-07

    The laser wavelength constitutes a key parameter in ultraviolet-matrix-assisted laser desorption ionization-mass spectrometry (UV-MALDI-MS). Optimal analytical results are only achieved at laser wavelengths that correspond to a high optical absorption of the matrix. In the presented work, the wavelength dependence and the contribution of matrix proton affinity to the MALDI process were investigated. A tunable dye laser was used to examine the wavelength range between 280 and 355 nm. The peptide and matrix ion signals recorded as a function of these irradiation parameters are displayed in the form of heat maps, a data representation that furnishes multidimensional data interpretation. Matrixes with a range of proton affinities from 809 to 866 kJ/mol were investigated. Among those selected are the standard matrixes 2,5-dihydroxybenzoic acid (DHB) and α-cyano-4-hydroxycinnamic acid (HCCA) as well as five halogen-substituted cinnamic acid derivatives, including the recently introduced 4-chloro-α-cyanocinnamic acid (ClCCA) and α-cyano-2,4-difluorocinnamic acid (DiFCCA) matrixes. With the exception of DHB, the highest analyte ion signals were obtained toward the red side of the peak optical absorption in the solid state. A stronger decline of the molecular analyte ion signals generated from the matrixes was consistently observed at the low wavelength side of the peak absorption. This effect is mainly the result of increased fragmentation of both analyte and matrix ions. Optimal use of multiply halogenated matrixes requires adjustment of the excitation wavelength to values below that of the standard MALDI lasers emitting at 355 (Nd:YAG) or 337 nm (N(2) laser). The combined data provide new insights into the UV-MALDI desorption/ionization processes and indicate ways to improve the analytical sensitivity.

  15. Semi-empirical formulas for sputtering yield

    International Nuclear Information System (INIS)

    Yamamura, Yasumichi

    1994-01-01

    When charged particles, electrons, light and so on are irradiated on solid surfaces, the materials are lost from the surfaces, and this phenomenon is called sputtering. In order to understand sputtering phenomenon, the bond energy of atoms on surfaces, the energy given to the vicinity of surfaces and the process of converting the given energy to the energy for releasing atoms must be known. The theories of sputtering and the semi-empirical formulas for evaluating the dependence of sputtering yield on incident energy are explained. The mechanisms of sputtering are that due to collision cascade in the case of heavy ion incidence and that due to surface atom recoil in the case of light ion incidence. The formulas for the sputtering yield of low energy heavy ion sputtering, high energy light ion sputtering and the general case between these extreme cases, and the Matsunami formula are shown. At the stage of the publication of Atomic Data and Nuclear Data Tables in 1984, the data up to 1983 were collected, and about 30 papers published thereafter were added. The experimental data for low Z materials, for example Be, B and C and light ion sputtering data were reported. The combination of ions and target atoms in the collected sputtering data is shown. The new semi-empirical formula by slightly adjusting the Matsunami formula was decided. (K.I.)

  16. Bond yield curve construction

    Directory of Open Access Journals (Sweden)

    Kožul Nataša

    2014-01-01

    Full Text Available In the broadest sense, yield curve indicates the market's view of the evolution of interest rates over time. However, given that cost of borrowing it closely linked to creditworthiness (ability to repay, different yield curves will apply to different currencies, market sectors, or even individual issuers. As government borrowing is indicative of interest rate levels available to other market players in a particular country, and considering that bond issuance still remains the dominant form of sovereign debt, this paper describes yield curve construction using bonds. The relationship between zero-coupon yield, par yield and yield to maturity is given and their usage in determining curve discount factors is described. Their usage in deriving forward rates and pricing related derivative instruments is also discussed.

  17. Measurements of fission yields

    International Nuclear Information System (INIS)

    Denschlag, H.O.

    2000-01-01

    After some historical introductory remarks on the discovery of nuclear fission and early fission yield determinations, the present status of knowledge on fission yields is briefly reviewed. Practical and fundamental reasons motivating the pursuit of fission yield measurements in the coming century are pointed out. Recent results and novel techniques are described that promise to provide new interesting insights into the fission process during the next century. (author)

  18. Fission product yields

    International Nuclear Information System (INIS)

    Valenta, V.; Hep, J.

    1978-01-01

    Data are summed up necessary for determining the yields of individual fission products from different fissionable nuclides. Fractional independent yields, cumulative and isobaric yields are presented here for the thermal fission of 235 U, 239 Pu, 241 Pu and for fast fission (approximately 1 MeV) of 235 U, 238 U, 239 Pu, 241 Pu; these values are included into the 5th version of the YIELDS library, supplementing the BIBFP library. A comparison is made of experimental data and possible improvements of calculational methods are suggested. (author)

  19. Yield degradation in inertial-confinement-fusion implosions due to shock-driven kinetic fuel-species stratification and viscous heating

    Science.gov (United States)

    Taitano, W. T.; Simakov, A. N.; Chacón, L.; Keenan, B.

    2018-05-01

    Anomalous thermonuclear yield degradation (i.e., that not describable by single-fluid radiation hydrodynamics) in Inertial Confinement Fusion (ICF) implosions is ubiquitously observed in both Omega and National Ignition experiments. Multiple experimental and theoretical studies have been carried out to investigate the origin of such a degradation. Relative concentration changes of fuel-ion species, as well as kinetically enhanced viscous heating, have been among possible explanations proposed for certain classes of ICF experiments. In this study, we investigate the role of such kinetic plasma effects in detail. To this end, we use the iFP code to perform multi-species ion Vlasov-Fokker-Planck simulations of ICF capsule implosions with the fuel comprising various hydrodynamically equivalent mixtures of deuterium (D) and helium-3 (3He), as in the original Rygg experiments [J. R. Rygg et al., Phys. Plasmas 13, 052702 (2006)]. We employ the same computational setup as in O. Larroche [Phys. Plasmas 19, 122706 (2012)], which was the first to simulate the experiments kinetically. However, unlike the Larroche study, and in partial agreement with experimental data, we find a systematic yield degradation in multi-species simulations versus averaged-ion simulations when the D-fuel fraction is decreased. This yield degradation originates in the fuel-ion species stratification induced by plasma shocks, which imprints the imploding system and results in the relocation of the D ions from the core of the capsule to its periphery, thereby reducing the yield relative to a non-separable averaged-ion case. By comparing yields from the averaged-ion kinetic simulations and from the hydrodynamic scaling, we also observe yield variations associated with ion kinetic effects other than fuel-ion stratification, such as ion viscous heating, which is typically neglected in hydrodynamic implosions' simulations. Since our kinetic simulations are driven by hydrodynamic boundary conditions at the

  20. Forage yield and quality of kenaf ( Hibiscus cannabinus L.) for ...

    African Journals Online (AJOL)

    This study was carried out to evaluate 40 kenaf accessions for forage yield and quality at Universiti Putra Malaysia in 2009. Forage yield and quality traits were measured at the initial flowering stage. The kenaf accessions showed highly significant variation for most of trait studied. Plant dry matter yield ranged from 5286 kg ...

  1. Performance of a procedure for yield estimation in fruit orchards

    DEFF Research Database (Denmark)

    Aravena Zamora, Felipe; Potin, Camila; Wulfsohn, Dvora-Laio

    Early estimation of expected fruit tree yield is important for the market planning and for growers and exporters to plan for labour and boxes. Large variations in tree yield may be found, posing a challenge for accurate yield estimation. We evaluated a multilevel systematic sampling procedure...

  2. Structure of ion-implanted ceramics

    International Nuclear Information System (INIS)

    Naramoto, Hiroshi

    1983-01-01

    The variation of structure of LiF, MgO, Al 2 O 3 and TiO 2 accompanying annealing after ion implantation is explained. The analysis of structure is usually made by the perturbed gamma ray angular correlation, the internal electron Moessbauer method, or the ion scattering method. The results of analyses are discussed for alkali ion implantation, Fe-ion implantation, In-ion implantation, Au-ion implantation, Pt-ion implantation, Pb-ion implantation and transition metal ion implantation. The coupling of the implanted elements with lattice defects and matrix elements, and the compatibility between deposited elements and matrix crystal lattice were studied. The variation of physical properties due to ion implantation such as phase transition, volume change, the control of single crystal region, and the variation of hardness near surface were investigated, and the examples are presented. (Kato, T.)

  3. LET dependence of scintillation yields in liquid argon

    Energy Technology Data Exchange (ETDEWEB)

    Doke, Tadayoshi; Hitachi, Akira; Kikuchi, Jun; Crawford, H J; Lindstrom, P J; Masuda, Kimiaki; Shibamura, Eido; Takahashi, Tan

    1988-06-01

    Scintillation yields (scintillation intensity per unit absorbed energy) in liquid argon for ionizing particles are reviewed as a function of LET for the particles. The maximum scintillation yield, which is obtained for relativistic heavy ions from Ne to La, is about 1.2 times larger than that for gamma rays in NaI(Tl) crystal. In the low LET region, the scintillation yields for relativistic electrons, protons and He ions are 10-20% lower than the maximum yield. This tendency can be explained by taking into account the existence of the electrons which have escaped from their parent ions. In the high LET region, a quenching effect due to high ionization density is observed for alpha particles, fission fragments and relativistic Au ions.

  4. Ion thruster performance model

    International Nuclear Information System (INIS)

    Brophy, J.R.

    1984-01-01

    A model of ion thruster performance is developed for high flux density cusped magnetic field thruster designs. This model is formulated in terms of the average energy required to produce an ion in the discharge chamber plasma and the fraction of these ions that are extracted to form the beam. The direct loss of high energy (primary) electrons from the plasma to the anode is shown to have a major effect on thruster performance. The model provides simple algebraic equations enabling one to calculate the beam ion energy cost, the average discharge chamber plasma ion energy cost, the primary electron density, the primary-to-Maxwellian electron density ratio and the Maxwellian electron temperature. Experiments indicate that the model correctly predicts the variation in plasma ion energy cost for changes in propellant gas (Ar, Kr, and Xe), grid transparency to neutral atoms, beam extraction area, discharge voltage, and discharge chamber wall temperature

  5. Ion-ion collisions

    International Nuclear Information System (INIS)

    Salzborn, Erhard; Melchert, Frank

    2000-01-01

    Collisions between ions belong to the elementary processes occurring in all types of plasmas. In this article we give a short overview about collisions involving one-electron systems. For collisions involving multiply-charged ions we limit the discussion to one specific quasi-one-electron system. (author)

  6. Remarkably high apparent quantum yield of the overall photocatalytic H2O splitting achieved by utilizing Zn ion added Ga2O3 prepared using dilute CaCl2 solution.

    Science.gov (United States)

    Sakata, Yoshihisa; Hayashi, Takuya; Yasunaga, Ryō; Yanaga, Nobuyuki; Imamura, Hayao

    2015-08-21

    Remarkably high photocatalytic activity for the overall H2O splitting, where the activity was 32 mmol h(-1) for H2 production and 16 mmol h(-1) for O2 production under irradiation from a 450 W high-pressure Hg lamp and the apparent quantum yield (AQY) was 71% under irradiation at 254 nm, was achieved by utilizing a Rh(0.5)Cr(1.5)O3(Rh; 0.5 wt%)/Zn(3 mol%)-Ga2O3 photocatalyst when Ga2O3 was prepared using dilute CaCl2 aqueous solution having a concentration of 0.001 mol l(-1).

  7. The Effect of Gas Ion Bombardment on the Secondary Electron Yield of TiN, TiCN and TiZrV Coatings For Suppressing Collective Electron Effects in Storage Rings

    International Nuclear Information System (INIS)

    Le Pimpec, F.; Kirby, R.E.; King, F.K.; Pivi, M.

    2006-01-01

    In many accelerator storage rings running positively charged beams, ionization of residual gas and secondary electron emission (SEE) in the beam pipe will give rise to an electron cloud which can cause beam blow-up or loss of the circulating beam. A preventative measure that suppresses electron cloud formation is to ensure that the vacuum wall has a low secondary emission yield (SEY). The SEY of thin films of TiN, sputter deposited Non-Evaporable Getters and a novel TiCN alloy were measured under a variety of conditions, including the effect of re-contamination from residual gas

  8. Independent isomer yield ratio of 90Rb

    International Nuclear Information System (INIS)

    Reeder, P.L.; Warner, R.A.; Ford, G.P.; Willmes, H.

    1985-05-01

    The independent isomer yield ratio for 90 Rb from thermal neutron fission of 235 U has been measured by use of a new technique involving a pulsed reactor and an on-line mass spectrometer facility. The apparent isomer yield ratio was measured for different ion collection time intervals and extrapolated to zero collection time to eliminate interference from 90 Kr decay. The observed isomer yield ratio of 8.7 +- 1.0 is one of the largest ratios measured for a low energy fission process. However, a statistical model analysis shows that the average angular momentum ( = 4.5) deduced from this isomer yield ratio is consistent with average angular momentum for other products from low energy fission. 7 refs

  9. Secondary ion emission

    International Nuclear Information System (INIS)

    Krohn, V.E.

    1976-01-01

    The Saha-Langmuir equation that describes the equilibrium emission process, surface ionization, has also been used to describe ion yields observed in the non-equilibrium emission process, sputtering. In describing sputtering, it is probably best to include the potential due to an image charge in the expression for negative as well as positive ion yield and to treat the work function and the temperature as parameters having limited physical significance. Arguments are presented to suggest that sputtered material is not emitted from a plasma. (Auth.)

  10. Slope Controls Grain Yield and Climatic Yield in Mountainous Yunnan province, China

    Science.gov (United States)

    Duan, X.; Rong, L.; Gu, Z.; Feng, D.

    2017-12-01

    Mountainous regions are increasingly vulnerable to food insecurity because of limited arable land, growing population pressure, and climate change. Development of sustainable mountain agriculture will require an increased understanding of the effects of environmental factors on grain and climatic yields. The objective of this study was to explore the relationships between actual grain yield, climatic yield, and environmental factors in a mountainous region in China. We collected data on the average grain yield per unit area in 119 counties in Yunnan province from 1985 to 2012, and chose 17 environmental factors for the same period. Our results showed that actual grain yield ranged from 1.43 to 6.92 t·ha-1, and the climatic yield ranged from -0.15 to -0.01 t·ha-1. Lower climatic yield but higher grain yield was generally found in central areas and at lower slopes and elevations in the western and southwestern counties of Yunnan province. Higher climatic yield but lower grain yield were found in northwestern parts of Yunnan province on steep slopes. Annual precipation and temperature had a weak influence on the climatic yield. Slope explained 44.62 and 26.29% of the variation in grain yield and climatic yield. The effects of topography on grain and climatic yields were greater than climatic factors. Slope was the most important environmental variable for the variability in climatic and grain yields in the mountainous Yunnan province due to the highly heterogeneous topographic conditions. Conversion of slopes to terraces in areas with higher climatic yields is an effective way to maintain grain production in response to climate variability. Additionally, soil amendments and soil and water conservation measures should be considered to maintain soil fertility and aid in sustainable development in central areas, and in counties at lower slopes and elevations in western and southwestern Yunnan province.

  11. Duopigatron ion source studies

    International Nuclear Information System (INIS)

    Bacon, F.M.; Bickes, R.W. Jr.; O'Hagan, J.B.

    1978-07-01

    Ion source performance characteristics consisting of total ion current, ion energy distribution, mass distribution, and ion current density distribution were measured for several models of a duopigatron. Variations on the duopigatron design involved plasma expansion cup material and dimensions, secondary cathode material, and interelectrode spacings. Of the designs tested, the one with a copper and molybdenum secondary cathode and a mild steel plasma expansion cup proved to give the best results. The ion current density distribution was peaked at the center of the plasma expansion cup and fell off to 80 percent of the peak value at the cup wall for a cup 15.2 mm deep. A total ion current of 180 mA consisting of 60 to 70 percent atomic ions was produced with an arc current of 20 A and source pressure of 9.3 Pa. More shallow cups produced a larger beam current and a more sharply peaked ion current density distribution. Typical ion energy distributions were bell-shaped curves with a peak 10 to 20 V below anode potential and with ion energies extending 30 to 40 V on either side of the peak

  12. Soviet test yields

    Science.gov (United States)

    Vergino, Eileen S.

    Soviet seismologists have published descriptions of 96 nuclear explosions conducted from 1961 through 1972 at the Semipalatinsk test site, in Kazakhstan, central Asia [Bocharov et al., 1989]. With the exception of releasing news about some of their peaceful nuclear explosions (PNEs) the Soviets have never before published such a body of information.To estimate the seismic yield of a nuclear explosion it is necessary to obtain a calibrated magnitude-yield relationship based on events with known yields and with a consistent set of seismic magnitudes. U.S. estimation of Soviet test yields has been done through application of relationships to the Soviet sites based on the U.S. experience at the Nevada Test Site (NTS), making some correction for differences due to attenuation and near-source coupling of seismic waves.

  13. Precise measurements of the thick target neutron yields of the 7Li(p,n) reaction

    International Nuclear Information System (INIS)

    Matysiak, W.; Prestwich, W.V.; Byun, S.H.

    2011-01-01

    Thick target neutron yield of the 7 Li(p,n) 7 Be reaction was measured in the proton energy range from 1.95 to 2.3 MeV by determining induced activity of the 7 Be. A HPGe detector was used to detect the 478 keV gamma-rays emitted through 7 Be decay. A series of irradiations with nominal proton energies of 1.95, 2.0, 2.1, 2.2, and 2.3 MeV were carried out. In an independent experiment, raw neutron spectra were collected by a 3 He ion chamber for the same series of proton energies. From the raw neutron spectra, it was noted, that the effective proton energies were lower than the nominal by 50-58 keV. After corrections for the proton energy offsets were applied, the measured neutron yields matched the analytically calculated yields within 20%. Long term stability of neutron yield was tested at two nominal proton energies, 2.1 and 1.95 MeV over an experimental period of one year. The results show that the yield at 2.1 MeV was stable within rmse variation coefficient of 4.7% and remained consistent even when the lithium target was replaced, whereas at 1.95 MeV, the maximum fluctuations reached a factor of 10.

  14. Quantitative ion implantation

    International Nuclear Information System (INIS)

    Gries, W.H.

    1976-06-01

    This is a report of the study of the implantation of heavy ions at medium keV-energies into electrically conducting mono-elemental solids, at ion doses too small to cause significant loss of the implanted ions by resputtering. The study has been undertaken to investigate the possibility of accurate portioning of matter in submicrogram quantities, with some specific applications in mind. The problem is extensively investigated both on a theoretical level and in practice. A mathematical model is developed for calculating the loss of implanted ions by resputtering as a function of the implanted ion dose and the sputtering yield. Numerical data are produced therefrom which permit a good order-of-magnitude estimate of the loss for any ion/solid combination in which the ions are heavier than the solid atoms, and for any ion energy from 10 to 300 keV. The implanted ion dose is measured by integration of the ion beam current, and equipment and techniques are described which make possible the accurate integration of an ion current in an electromagnetic isotope separator. The methods are applied to two sample cases, one being a stable isotope, the other a radioisotope. In both cases independent methods are used to show that the implantation is indeed quantitative, as predicted. At the same time the sample cases are used to demonstrate two possible applications for quantitative ion implantation, viz. firstly for the manufacture of calibration standards for instrumental micromethods of elemental trace analysis in metals, and secondly for the determination of the half-lives of long-lived radioisotopes by a specific activity method. It is concluded that the present study has advanced quantitative ion implantation to the state where it can be successfully applied to the solution of problems in other fields

  15. Ion implantation

    International Nuclear Information System (INIS)

    Dearnaley, Geoffrey

    1975-01-01

    First, ion implantation in semiconductors is discussed: ion penetration, annealing of damage, gettering, ion implanted semiconductor devices, equipement requirements for ion implantation. The importance of channeling for ion implantation is studied. Then, some applications of ion implantation in metals are presented: study of the corrosion of metals and alloys; influence or ion implantation on the surface-friction and wear properties of metals; hyperfine interactions in implanted metals

  16. Improving growth and yield of cowpea by foliar application of ...

    African Journals Online (AJOL)

    Water stress impaired cowpea plant growth and decreased ion percentage and chlorophyll and carbohydrate concentration in the shoot as well as yield and its quality. Foliar-applied chitosan, in particular 250 mg/l, increased plant growth, yield and its quality as well as physiological constituents in plant shoot under stressed ...

  17. Theoretical lifetimes and fluorescence yields for multiply-ionized fluorine

    International Nuclear Information System (INIS)

    Tunnell, T.W.; Can, C.; Bhalla, C.P.

    1978-01-01

    Theoretical lifetimes and multiplet partial fluorescence yields for various fluorine ions with a single K-shell vacancy were calculated. For few-electron systems, the lifetimes and line fluorescence yields were computed in the intermediate coupling scheme with the inclusion of the effects arising from configuration interactions. 6 references

  18. Yield stress of alumina-zirconia suspensions

    International Nuclear Information System (INIS)

    Ramakrishnan, V.; Pradip; Malghan, S.G.

    1996-01-01

    The yield stress of concentrated suspensions of alumina, zirconia, and mixed alumina-zirconia powders was measured by the vane technique as a function of solids loading, relative amounts of alumina and zirconia, and pH. At the isoelectric point (IEP), the yield stress varied as the fourth power of the solids loading. The relative ratio of alumina and zirconia particles was important in determining the yield stress of the suspension at the IEP. The yield stress of single and mixed suspensions showed a marked variation with pH. The maximum value occurred at or near the IEP of the suspension. The effect of electrical double-layer forces on the yield stress can be described on the basis of the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. A normalized yield stress--that is, the ratio of the yield stress at a given pH to the yield stress at the IEP predicted by this model--showed good correlation with experimental data

  19. Collateral variations between the concentrations of mercury and other water soluble ions in volcanic ash samples and volcanic activity during the 2014-2016 eruptive episodes at Aso volcano, Japan

    Science.gov (United States)

    Marumoto, Kohji; Sudo, Yasuaki; Nagamatsu, Yoshizumi

    2017-07-01

    During 2014-2016, the Aso volcano, located in the center of the Kyushu Islands, Japan, erupted and emitted large amounts of volcanic gases and ash. Two episodes of the eruption were observed; firstly Strombolian magmatic eruptive episodes from 25 November 2014 to the middle of May 2015, and secondly phreatomagmatic and phreatic eruptive episodes from September 2015 to February 2016. Bulk chemical analyses on total mercury (Hg) and major ions in water soluble fraction in volcanic ash fall samples were conducted. During the Strombolian magmatic eruptive episodes, total Hg concentrations averaged 1.69 ± 0.87 ng g- 1 (N = 33), with a range from 0.47 to 3.8 ng g- 1. In addition, the temporal variation of total Hg concentrations in volcanic ash varied with the amplitude change of seismic signals. In the Aso volcano, the volcanic tremors are always observed during eruptive stages and quiet interludes, and the amplitudes of tremors increase at eruptive stages. So, the temporal variation of total Hg concentrations could provide an indication of the level of volcanic activity. During the phreatomagmatic and phreatic eruptive episodes, on the other hand, total Hg concentrations in the volcanic ash fall samples averaged 220 ± 88 ng g- 1 (N = 5), corresponding to 100 times higher than those during the Strombolian eruptive episode. Therefore, it is possible that total Hg concentrations in volcanic ash samples are largely varied depending on the eruptive type. In addition, the ash fall amounts were also largely different among the two eruptive episodes. This can be also one of the factors controlling Hg concentrations in volcanic ash.

  20. Study of the processes of ion pairs formation by the method of ion-ion coincidence: I2 and chlorine-containing hydrocarbons

    International Nuclear Information System (INIS)

    Golovin, A.V.

    1991-01-01

    A method of ion-ion coincidences was suggested to study the process of ion pairs formation during molecule photoionization. The principle of action of ion-ion coincidence method is based on recording of only the negative and positive ions that formed as a result of a molecule decomposition. The flowsheet of the facility of ion-ion coincidences was presented. The processes of ion pairs formation in iodine, chloroform, propyl-, n-propenyl-, tert.butyl- and benzyl-chlorides were studied. A simple model permitting to evaluate the dependence of quantum yield of ion pair formation on excitation energy was suggested

  1. Enhancement of HHG yield

    International Nuclear Information System (INIS)

    Serrat, C.; Biegert, J.

    2011-01-01

    A static electric field periodically distributed in space controls and enhances the yield in high harmonic generation. The method is relatively simple to implement and allows tuning from the extreme-ultraviolet to soft X-ray. The radiation yield is selectively enhanced due to symmetry breaking induced by a static electric field on the interaction between the driving laser and the medium. The enhanced spectral region is tuned by varying the periodicity of the static electric field. Simulations predict an increase of more than two orders of magnitude for harmonics in the water window spectral range.

  2. Accelerated yield learning in agressive lithography

    Science.gov (United States)

    Monahan, Kevin M.; Ashkenaz, Scott M.; Chen, Xing; Lord, Patrick J.; Merrill, Mark A.; Quattrini, Rich; Wiley, James N.

    2000-06-01

    As exposure wavelengths decrease from 248 nm to 193, 157, and even 13 nm (EUV), small process defects can cause collapse of the lithographic process window near the limits of resolution, particularly for the gate and contact structures in high- performance devices. Such sensitivity poses a challenge for lithography process module control. In this work, we show that yield loss can be caused by a combination of macro, micro, CD, and overlay defects. A defect is defined as any yield- affecting process variation. Each defect, regardless of cause, is assumed to have a specific 'kill potential.' The accuracy of the lithographic yield model can be improved by identifying those defects with the highest kill potential or, more importantly, those that pose the highest economic risk. Such economic considerations have led us to develop a simple heuristic model for understanding sampling strategies in defect metrology and for linking metrology capability to yield and profitability.

  3. Research with stored ions produced using synchrotron radiation

    International Nuclear Information System (INIS)

    Church, D.A.; Kravis, S.D.; Meron, M.; Johnson, B.M.; Jones, K.W.; Sellin, I.A.; O, C.S.; Levin, J.C.; Short, R.T.

    1987-01-01

    A distribution of argon ion charge states has been produced by inner shell photoionization of argon atoms using x-ray synchrotron radiation. These ions were stored in a Penning ion trap at moderate to very low well depths, and analog-detected yielding narrow charge-to-mass spectrum linewidths. Estimates of ion densities indicated that ion-ion collisional energy transfer should be rapid, leading to thermalization. Measurements using variants of this novel stored, multi-charged ion gas are considered

  4. Quartz crystal microbalance-based system for high-sensitivity differential sputter yield measurements

    International Nuclear Information System (INIS)

    Rubin, B.; Topper, J. L.; Farnell, C. C.; Yalin, A. P.

    2009-01-01

    We present a quartz crystal microbalance-based system for high sensitivity differential sputter yield measurements of different target materials due to ion bombardment. The differential sputter yields can be integrated to find total yields. Possible ion beam conditions include ion energies in the range of 30-350 eV and incidence angles of 0 deg. - 70 deg. from normal. A four-grid ion optics system is used to achieve a collimated ion beam at low energy (<100 eV) and a two-grid ion optics is used for higher energies (up to 750 eV). A complementary weight loss approach is also used to measure total sputter yields. Validation experiments are presented that confirm high sensitivity and accuracy of sputter yield measurements.

  5. Quantitative and compositional variations in milk yield of west ...

    African Journals Online (AJOL)

    apra.v4i3-4.49782 · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of Use · Contact AJOL · News. OTHER RESOURCES.

  6. Determinants of wheat yield variation of smallholders in South ...

    African Journals Online (AJOL)

    Cross-sectional data collected from randomly selected farm households and ordered logistic regression were used to attain the objective of the study. The study found out that seed rate, rates of herbicides and fungicides applications, use of hand weeding and agro-ecological location of household were significant factors ...

  7. Variations in some morphological and yield characteristics of ...

    African Journals Online (AJOL)

    L) Wilczek) was introduced into the agro-ecology of southeastern Nigeria. During a field evaluation of mungbean cultivars at Michael Okpara University of Agriculture, Umudike, Nigeria, nine (9) plants were observed to differ in some vegetative ...

  8. Yield and competition in barley variety mixtures

    Directory of Open Access Journals (Sweden)

    Kari Jokinen

    1991-09-01

    Full Text Available Competition between spring barley varieties and yield performance of two-, three and four-variety mixtures were studied in two replacement series field experiments. In the first experiment, repeated in three successive years (1983 —85 the components were the six-row varieties Agneta, Arra, Hja-673 and Porno. In the second experiment (1984, including two nitrogen doses (50 and 100 kgN/ha, both six-row (Agneta, Pomo and two-row (Ida, Kustaa varieties were used. Arra in the first and Agneta in the second experiment were the most competitive varieties. The results suggested that the fast growth of Arra at the beginning promoted its competitive ability. Increase in available nitrogen usually strengthened the competitiveness of Agneta. The observed competitive differences between varieties were not related to the earliness of a variety, neither to the morphological characters (two- and six-row varieties nor to the grain yield of a variety grown alone. The competitive ability was not always a stable character, the dominant suppression relationship varying from one environment to another (e.g. growing season, nitrogen dose. The observed overyielding was not statistically significant. The ratio of actual to expected yield and the relative yield total of several mixtures exceeded slightly one. As a conclusion, the yield advantage of mixtures was marginal. As a rule, the mixtures were not more stable than monocultures as determined by the coefficient of variation. However, the yield of some mixtures varied less than the yield of the most stable monoculture.

  9. Fusion at counterstreaming ion beams - ion optic fusion (IOF)

    International Nuclear Information System (INIS)

    Gryzinski, M.

    1981-01-01

    The results of investigation are briefly reviewed in the field of ion optic fusion performed at the Institute of Nuclear Research in Swierk. The ion optic fusion concept is based on the possibility of obtaining fusion energy at highly ordered motion of ions in counterstreaming ion beams. For this purpose TW ion beams must be produced and focused. To produce dense and charge-neutralized ion beams the selective conductivity and ballistic focusing ideas were formulated and used in a series of RPI devices with low-pressure cylindrical discharge between grid-type electrodes. 100 kA, 30 keV deuteron beams were successfully produced and focused into the volume of 1 cm 3 , yielding 10 9 neutrons per 200 ns shot on a heavy ice target. Cylindrically convergent ion beams with magnetic anti-defocusing were proposed in order to reach a positive energy gain at reasonable energy level. (J.U.)

  10. Estimating Corporate Yield Curves

    OpenAIRE

    Antionio Diaz; Frank Skinner

    2001-01-01

    This paper represents the first study of retail deposit spreads of UK financial institutions using stochastic interest rate modelling and the market comparable approach. By replicating quoted fixed deposit rates using the Black Derman and Toy (1990) stochastic interest rate model, we find that the spread between fixed and variable rates of interest can be modeled (and priced) using an interest rate swap analogy. We also find that we can estimate an individual bank deposit yield curve as a spr...

  11. Ion source of discharge type

    Energy Technology Data Exchange (ETDEWEB)

    Enchevich, I.B. [TRIUMF, Cyclotron Div., Vancouver, British Columbia (Canada); Korenev, S.A. [JINR, Hihg Energy Physics Lab., Dubna, Moscow (Russian Federation)

    1992-07-01

    A new scheme of ion source based on a dielectric surface sliding discharge is described. The conditions to form this type of discharge are analyzed and experimental results are shown. The main parameters of this ion source are: accelerating voltage U = 1/20kV; continuous extracted ion beam; current density j = 0.01/0.5 A/cm{sup 2}; ions of Cl, F, C, H; residual gas pressure P = 10{sup -6} Torr. A magnetic system is used to separate the different types of ions. The dielectric material in the discharge circuit (anode plasma emitter) defines the type of ions. The emission characteristics of plasma emitter and the discharge parameters are presented. The ion current yield satisfies the Child-Langmuir law. (author)

  12. Ion source of discharge type

    International Nuclear Information System (INIS)

    Enchevich, I.B.; Korenev, S.A.

    1992-07-01

    A new scheme of ion source based on a dielectric surface sliding discharge is described. The conditions to form this type of discharge are analyzed and experimental results are shown. The main parameters of this ion source are: accelerating voltage U = 1/20kV; continuous extracted ion beam; current density j = 0.01/0.5 A/cm 2 ; ions of Cl, F, C, H; residual gas pressure P = 10 -6 Torr. A magnetic system is used to separate the different types of ions. The dielectric material in the discharge circuit (anode plasma emitter) defines the type of ions. The emission characteristics of plasma emitter and the discharge parameters are presented. The ion current yield satisfies the Child-Langmuir law. (author)

  13. Study of the secondary electron emission during bombardment of metal targets by positive D{sup +} and D{sub 2}{sup +} ions (1960); Etude de l'emission secondaire d'electrons au cours du bombardement de cibles metalliques par des ions positifs D{sup +} et D{sub 2}{sup +} (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, J [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Prelec, K [Institut Rudjer Boskovic, Zagreb (Croatia)

    1960-07-01

    The secondary electron yield {gamma}-bar due to primary positive ions D{sup +} and D{sup +}{sub 2} has been measured in the 70 keV to 300 keV ion energy range. Several metallic targets have been used. The variation of this yield with the angle of incidence is proportional to sec {theta} where {theta} is the angle between the beam of primary ions and the normal to the target surface. The values {gamma}-bar decrease for increasing energy ions. At a given energy all the targets tried gave approximately the same electron yield. (author) [French] Le facteur d'emission secondaire a ete mesure pour des ions positifs D{sup +} et D{sup +}{sub 2} ayant une energie comprise entre 70 keV et 300 keV, sur differentes cibles metalliques. La variation de ce facteur avec l'angle d'incidence suit une loi de la forme {gamma}{sub 0} sec {theta}, {theta} etant l'angle entre le faisceau et la normale a la cible. Les valeurs de {gamma}-bar trouvees decroissent lorsque l'energie des ions incidents augmente, mais sont assez voisines les unes des autres, a une energie donnee, pour les differentes cibles essayees. (auteur)

  14. Comparing predicted yield and yield stability of willow and Miscanthus across Denmark

    DEFF Research Database (Denmark)

    Larsen, Søren; Jaiswal, Deepak; Bentsen, Niclas Scott

    2016-01-01

    was 12.1 Mg DM ha−1 yr−1 for willow and 10.2 Mg DM ha−1 yr−1 for Miscanthus. Coefficent of variation as a measure for yield stability was poorest on the sandy soils of northern and western Jutland and the year-to-year variation in yield was greatest on these soils. Willow was predicted to outyield...... Miscanthus on poor, sandy soils whereas Miscanthus was higher yielding on clay-rich soils. The major driver of yield in both crops was variation in soil moisture, with radiation and precipitation exerting less influence. This is the first time these two major feedstocks for northern Europe have been compared....... The semi-mechanistic crop model BioCro was used to simulate the production of both short rotation coppice (SRC) willow and Miscanthus across Denmark. Predictions were made from high spatial resolution soil data and weather records across this area for 1990-2010. The potential average, rain-fed mean yield...

  15. Yields of clustered DNA damage induced by charged-particle radiations of similar kinetic energy per nucleon: LET dependence in different DNA microenvironments

    International Nuclear Information System (INIS)

    Keszenman, D.J.; Sutherland, B.M.

    2010-01-01

    To determine the linear energy transfer (LET) dependence of the biological effects of densely ionizing radiation in relation to changes in the ionization density along the track, we measured the yields and spectrum of clustered DNA damages induced by charged particles of different atomic number but similar kinetic energy per nucleon in different DNA microenvironments. Yeast DNA embedded in agarose in solutions of different free radical scavenging capacity was irradiated with 1 GeV protons, 1 GeV/nucleon oxygen ions, 980 MeV/nucleon titanium ions or 968 MeV/nucleon iron ions. The frequencies of double-strand breaks (DSBs), abasic sites and oxypurine clusters were quantified. The total DNA damage yields per absorbed dose induced in non-radioquenching solution decreased with LET, with minor variations in radioquenching conditions being detected. However, the total damage yields per particle fluence increased with LET in both conditions, indicating a higher efficiency per particle to induce clustered DNA damages. The yields of DSBs and non-DSB clusters as well as the damage spectra varied with LET and DNA milieu, suggesting the involvement of more than one mechanism in the formation of the different types of clustered damages.

  16. Effect of nitrogen and water deficit type on the yield gap between the potential and attainable wheat yield

    Directory of Open Access Journals (Sweden)

    Jiangang Liu

    2015-12-01

    Full Text Available Water deficit and N fertilizer are the two primary limiting factors for wheat yield in the North China plain, the most important winter wheat (Triticum aestivum L. production area in China. Analyzing the yield gap between the potential yield and the attainable yield can quantify the potential for increasing wheat production and exploring the limiting factors to yield gap in the high-yielding farming region of North China Plain. The Decision Support System for Agrotechnology Transfer (DSSAT model was used to identify methods to increase the grain yield and decrease the gap. In order to explore the impact of N and cultivars on wheat yield in the different drought types, the climate conditions during 1981 to 2011 growing seasons was categorized into low, moderate, and severe water deficit classes according to the anomaly percentage of the water deficit rate during the entire wheat growing season. There are differences (P < 0.0001 in the variations of the potential yields among three cultivars over 30 yr. For all three water deficit types, the more recent cultivars Jimai22 and Shijiazhuang8 had higher yields compared to the older 'Jinan17'. As the N fertilizer rate increased, the yield gap decreased more substantially during the low water deficit years because of the significant increase in attainable yield. Overall, the yield gaps were smaller with less water stress. Replacement of cultivars and appropriate N fertilizer application based on the forecasted drought types can narrow the yield gap effectively.

  17. Status of fission yield measurements

    International Nuclear Information System (INIS)

    Maeck, W.J.

    1979-01-01

    Fission yield measurement and yield compilation activities in the major laboratories of the world are reviewed. In addition to a general review of the effort of each laboratory, a brief summary of yield measurement activities by fissioning nuclide is presented. A new fast reactor fission yield measurement program being conducted in the US is described

  18. Stored ions in the Paul trap. Preliminary investigations on life-time measurement of the metastable 6D3/2 state of 226Ra+, storage properties of 138Ba+ and 28N2+ at variation of the buffer-gas pressure

    International Nuclear Information System (INIS)

    Leuthner, Heiko

    2011-01-01

    Paul-traps are a widely used tool in scientific research and play an important role in atomic physics and mass spectrometry. (1) From the earth-alkaline ions only spectroscopic data of Ra + are lacking. Those are important for the test of theoretical models and for a future atomic parity violation experiment. The first part of this work describes the setting up of a Paul-trap based Laser-experiment for measuring the lifetime of the 6D 3/2 state of 226 Ra + . Basic tests with 138 Ba + ions are presented. (2) Damping and space charge effects on resonances in the stability region strongly affect the use of Paul-traps in mass spectrometry and analysis of reaction products. The second part of this work presents detailed investigations on the storage of big, buffer-gas-cooled ion clouds in two different Paul-trap experiments; the first of them uses 138 Ba + ions detected continuously by electronic and optical detection systems, the second one uses N 2 + molecular ions and an automated destructive time-of-flight-detection method. A high precision measurement with N 2 + of the first stability region of the trap not only gives the possibility of direct comparison of experimental and theoretical resonances but also provides absolute ion numbers over the whole region for the first time. Unlike previous measurements, the investigations on nonlinear resonances where done on the superimposed stability regions of 4 simultaneously stored ion species. The nonlinear resonances were studied by varying buffer gas pressure and ion number and showed collective resonances without external excitation. By varying the buffer gas pressure the spatial distribution of a Ba + -ion cloud was investigated as well as the change of the optimal storing parameters using N 2 + -ions. Optimum Pressures for catching and trapping of ions turned out to be unequal. Shape and position of externally excited collective and individual resonances were studied under variation of ion number, buffer-gas pressure

  19. Combined sputtering yield and surface topography development studies on Si

    International Nuclear Information System (INIS)

    Carter, G.; Nobes, M.J.; Lewis, G.W.; Whitton, J.L.

    1981-01-01

    The sputtering yield-incidence angle function has been measured for 8 keV Ar + ions incident on Si by direct scanning electron microscope observation of the depths of sputtered craters on substrate boundaries. This function displays a maximum sputtering yield at an angle thetasub(p) approximately equal to 40 0 to the surface normal. The sequential ion fluence dependence of features developed beneath local surface contaminant was then studied, quasi dynamically, in the same on-line ion source-S.E.M. system. During erosion of the contaminant a steeply elevated pillar of Si forms, which then transforms to a cone, again of high elevation angle >>thetasub(p). This cone is gradually eroded into the surrounding surface with no special significance associated with orientations of angle thetasub(p). Pedal depressions surrounding the pillar-cone system are also noted. The reasons for these observations and their relevance to ion beam surface channel etching are discussed. (Auth.)

  20. Ion optics in an ion source system

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Salam, F W; Moustafa, O A; El-Khabeary, H [Accelerators Dept, Nuclear Research Center, Atomic Energy Authority, Cairo (Egypt)

    1997-12-31

    An analysis of ion beams from an ion source which consisted of a hemispherical anode, a plane earthed cathode, and a focusing electrode has been carried out. The focal properties of such electrode arrangement were studied using axially symmetric fields. Axial and radial electric fields were obtained as functions of the axial distance. It was found that the radial component of the gradient of potential pushes the ions towards the axis, which indicates the convergent action of the system. The effect of voltage variation between the boundary and the focusing electrode on the position of the plasma boundary are given using the experimental data of the ion source characteristics and its geometrical parameters. The advantages of plasma diffusing outside the source through a small aperture were used by applying a potential to the focusing electrode. It was possible to extract a large ion current from the expanded plasma. The system constituted a lens with a focal length of 29.4 mm. 7 figs.

  1. Multiply charged ions from solid substances with the mVINIS Ion Source

    International Nuclear Information System (INIS)

    Dragani, I; Nedeljkovi, T; Jovovi, J; Siljegovic, M; Dobrosavljevic, A

    2007-01-01

    We have used the well known metal-ions-from-volatile-compounds (MIVOC) method at the mVINIS Ion Source to produce the multiply charged ion beams form solid substances. Based on this method the very intense and stable multiply charged ion beams of several solid substances having the high melting points were extracted. The ion yields and the spectra of multiply charged ion beams obtained from solid materials like Fe and Hf will be presented. We have utilized the multiply charged ion beams from solid substances to irradiate the polymers, fullerenes and glassy carbon at the low energy channel for modification of materials

  2. Fusion Yield Enhancement in Magnetized Laser-Driven Implosions

    International Nuclear Information System (INIS)

    Chang, P. Y.; Fiksel, G.; Hohenberger, M.; Knauer, J. P.; Marshall, F. J.; Betti, R.; Meyerhofer, D. D.; Seguin, F. H.; Petrasso, R. D.

    2011-01-01

    Enhancement of the ion temperature and fusion yield has been observed in magnetized laser-driven inertial confinement fusion implosions on the OMEGA Laser Facility. A spherical CH target with a 10 atm D 2 gas fill was imploded in a polar-drive configuration. A magnetic field of 80 kG was embedded in the target and was subsequently trapped and compressed by the imploding conductive plasma. As a result of the hot-spot magnetization, the electron radial heat losses were suppressed and the observed ion temperature and neutron yield were enhanced by 15% and 30%, respectively.

  3. Precise measurements of the thick target neutron yields of the {sup 7}Li(p,n) reaction

    Energy Technology Data Exchange (ETDEWEB)

    Matysiak, W., E-mail: matysiw@mcmaster.ca [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ont., L8S 4K1 (Canada); Prestwich, W.V.; Byun, S.H. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ont., L8S 4K1 (Canada)

    2011-07-01

    Thick target neutron yield of the {sup 7}Li(p,n){sup 7}Be reaction was measured in the proton energy range from 1.95 to 2.3 MeV by determining induced activity of the {sup 7}Be. A HPGe detector was used to detect the 478 keV gamma-rays emitted through {sup 7}Be decay. A series of irradiations with nominal proton energies of 1.95, 2.0, 2.1, 2.2, and 2.3 MeV were carried out. In an independent experiment, raw neutron spectra were collected by a {sup 3}He ion chamber for the same series of proton energies. From the raw neutron spectra, it was noted, that the effective proton energies were lower than the nominal by 50-58 keV. After corrections for the proton energy offsets were applied, the measured neutron yields matched the analytically calculated yields within 20%. Long term stability of neutron yield was tested at two nominal proton energies, 2.1 and 1.95 MeV over an experimental period of one year. The results show that the yield at 2.1 MeV was stable within rmse variation coefficient of 4.7% and remained consistent even when the lithium target was replaced, whereas at 1.95 MeV, the maximum fluctuations reached a factor of 10.

  4. Yield performance of brassica varieties under rainfed condition

    International Nuclear Information System (INIS)

    Hassan, M.Z.U.; Wahla, A.J.; Waqar, M.Q.

    2014-01-01

    A field study was conducted to evaluate crop growth and seed yield performance of Brassica varieties under Rainfed conditions. The varieties, included in the study, were BSA, Zafar-2000, Pakola, Con.1, Con.2, Abaseen, Rainbow, SPS-5, Bard-1, and KJ-119. KJ-119 (2500.0 KG/HA) among Brassica juncea L. varieties and Abaseen (2425.9 kg/ha) among Brassica napusL. Varieties produced with maximum seed yield as compared to rest of varieties. Significantly, minimum seed yield was observed in check variety BSA. The significant difference in seed yield of Brassica varieties, Abaseen and KJ 119, was attributed to improve yield components over other varieties. Maximum pods per plant and seeds per pod led these varieties to attain maximum yield. Inspite of weather variations existence during years 2007-09,the same varieties produced with maximum seed yield. (author)

  5. Influence of surface topography on the sputtering yields of silver

    International Nuclear Information System (INIS)

    Pan Jisheng; Wang Zhenxia; Tao Zhenlan; Zhang Jiping

    1992-01-01

    The sputtering yields of silver have been measured as a function of the fluence of incident Ar + ions (27 keV) using the collector technique and RBS analysis. The irradiated surface was examined by scanning electron microscopy (SEM). It is shown that the sputtering yields of surfaces with topography are enhanced relative to smooth surfaces of silver, but the extent of the enhancement depends on the irradiation dose. The experimental results can be explained assuming that the surface topography and sputtering yield are a function of incident angle. It is obvious that the surface topography is an important factor to influence the sputtering yield. The term ''apparent sputtering yield'' has specifically been used when referring to the experimental sputtering yield of a surface with topography, to emphasize the difference with a smooth surface. (orig.)

  6. Soybean growth and yield under cover crops

    Directory of Open Access Journals (Sweden)

    Priscila de Oliveira

    2013-04-01

    Full Text Available The use of cover crops in no-tillage systems can provide better conditions for the development of soybean plants with positive effects on grain yield and growth analysis techniques allow researchers to characterize and understand the behavior of soybean plants under different straw covers. Thus, the aim of this study was to characterize, using growth analysis, yield components and agronomic performance of soybean under common bean, Brachiaria brizantha and pearl millet straws. The experiment was performed on a soil under cerrado in the municipality of Santo Antônio de Goiás, GO. The experiment was arranged in a randomized complete block design with three treatments (cover crops and five replications. Soybean grain yield was lower in the B. brizantha straw treatment (3,708 kg ha-1 than both in the pearl millet (4.772 kg ha-1 and common bean straw treatments (5,200 kg ha-1. The soybean growth analysis in B. brizantha, pearl millet and common bean allowed characterizing the variation in the production of dry matter of leaves, stems, pods and total and leaf area index that provided different grain yields. The cover crop directly affects the soybean grain yield.

  7. Desorption of Cs+ ions with fast incident atomic and molecular ions

    International Nuclear Information System (INIS)

    Salehpour, M.; Hunt, J.E.; Tou, L.C.; Hedin, A.; Sundqvist, B.

    1988-01-01

    Preliminary results on desorption yield measurements of secondary Cs + ions, desorbed as a result of the impact of C + , O + , CO + , O 2 + , CO 2 + and C 4 H 9 + incident ions, in the energy range of 950 keV--3.5 MeV are presented. Molecular beams are found to give high yields of secondary Cs + as a result of impact of O 2 + compared to O + incident ions, indicate no ''collective'' molecular effects. 23 refs., 1 fig

  8. Molecular effects in ion-electron emission from clean metal surfaces

    International Nuclear Information System (INIS)

    Baragiola, R.A.; Alonso, E.V.; Auciello, O.; Ferron, J.; Lantschner, G.; Oliva Florio, A.

    1978-01-01

    The authors have measured electron emission yields from clean Al, Cu and Ag under 2-50 keV H + , D + , H 2 + impact. It is found that molecular ion yields are lower than twice the yield of atomic ions. No isotope effects are observed for equal-velocity ions. (Auth.)

  9. Effect of Integrated Nutrient Management on Yield and Yield ...

    African Journals Online (AJOL)

    Declining soil fertility is one of the major problems causing yield reduction of barley ... (VC) with inorganic NP on growth, yield and yield components of food barley. ... The experiments were laid out in a randomized complete block design with ...

  10. Direct Comparison of Biologically Optimized Spread-out Bragg Peaks for Protons and Carbon Ions

    International Nuclear Information System (INIS)

    Wilkens, Jan J.; Oelfke, Uwe

    2008-01-01

    Purpose: In radiotherapy with hadrons, it is anticipated that carbon ions are superior to protons, mainly because of their biological properties: the relative biological effectiveness (RBE) for carbon ions is supposedly higher in the target than in the surrounding normal tissue, leading to a therapeutic advantage over protons. The purpose of this report is to investigate this effect by using biological model calculations. Methods and Materials: We compared spread-out Bragg peaks for protons and carbon ions by using physical and biological optimization. The RBE for protons and carbon ions was calculated according to published biological models. These models predict increased RBE values in regions of high linear energy transfer (LET) and an inverse dependency of the RBE on dose. Results: For pure physical optimization, protons yield a better dose distribution along the central axis. In biologically optimized plans, RBE variations for protons were relatively small. For carbon ions, high RBE values were found in the high-LET target region, as well as in the low-dose region outside the target. This means that the LET dependency and dose dependency of the RBE can cancel each other. We show this for radioresistant tissues treated with two opposing beams, for which the predicted carbon RBE within the target volume was lower than outside. Conclusions: For tissue parameters used in this study, the model used does not predict a biologic advantage of carbon ions. More reliable model parameters and clinical trials are necessary to explore the true potential of radiotherapy with carbon ions

  11. Yield enhancement with DFM

    Science.gov (United States)

    Paek, Seung Weon; Kang, Jae Hyun; Ha, Naya; Kim, Byung-Moo; Jang, Dae-Hyun; Jeon, Junsu; Kim, DaeWook; Chung, Kun Young; Yu, Sung-eun; Park, Joo Hyun; Bae, SangMin; Song, DongSup; Noh, WooYoung; Kim, YoungDuck; Song, HyunSeok; Choi, HungBok; Kim, Kee Sup; Choi, Kyu-Myung; Choi, Woonhyuk; Jeon, JoongWon; Lee, JinWoo; Kim, Ki-Su; Park, SeongHo; Chung, No-Young; Lee, KangDuck; Hong, YoungKi; Kim, BongSeok

    2012-03-01

    A set of design for manufacturing (DFM) techniques have been developed and applied to 45nm, 32nm and 28nm logic process technologies. A noble technology combined a number of potential confliction of DFM techniques into a comprehensive solution. These techniques work in three phases for design optimization and one phase for silicon diagnostics. In the DFM prevention phase, foundation IP such as standard cells, IO, and memory and P&R tech file are optimized. In the DFM solution phase, which happens during ECO step, auto fixing of process weak patterns and advanced RC extraction are performed. In the DFM polishing phase, post-layout tuning is done to improve manufacturability. DFM analysis enables prioritization of random and systematic failures. The DFM technique presented in this paper has been silicon-proven with three successful tape-outs in Samsung 32nm processes; about 5% improvement in yield was achieved without any notable side effects. Visual inspection of silicon also confirmed the positive effect of the DFM techniques.

  12. 氮离子束注入和钴60伽玛辐射对大豆产量性状和品质的影响%Effects of Nitrogen Ion Beam Implantation and 60Co-γ Irradiation on Yield Traits and Quality of Soybean

    Institute of Scientific and Technical Information of China (English)

    季良; 王仙; 彭琳; 聂石辉

    2013-01-01

    Selection of materials, mutagenic methods and doses are very important in mutation breeding. The objectives of this experiment was to discuss the mutation breeding technique of soybean by nitrogen ion beam implantation and 60Co-γ ray radiation. The dried seeds of four soybean varieties were treated by nitrogen ion beam implantation including 4 × 1016 ,6 × 1016 and 8 × 1016 N+ ·cm-2 and 60Co-γ ray irradiation of 100,150 and 200 Gy. The biological effects of two treatments on yield traits and quality of M6 generation were compared under the same planting conditions. The results indicated that compared with control, 4×l016 and 6 ×l0l6N+ ·cm-2 increased pods per plant(P <0. 05) and yield(P <0. 01 )of Xindadou 3 significantly;8 × 1016 ,6 × 1016and 100 Gy60Co-γ irradiation decreased seeds number and weight per plant(P <0. 05) ,100-seed weight(P< 0.05)and protein content of He99-756,respectively. 100,150 and 200 Gy60Co-γ irradiation increased fat content(P<0.05)of He99-756;4×l016and 8×l016N+ ·cm-2,100 and 200 Gy60Co-γ irradiation decreased seeds weight per plant(P <0. 05) of Xindadou 8 ,4 × 1016 ,6 × 1016 N+ ·cm-2 and 200 Gy60Co-γ irradiation increased yield of Xindadou 8 significantly;nitrogen ion beam implantation and 60Co-γ irradiation had no effect on the yield,yield components and quality of Shidadou 2. Thus the objectives of mutation breeding were determined according to sensitivity of materials, mutagenic methods and doses.%分别以3种剂量的N离子束注入(4×1016,6×1016和8×1016 N+ ·cm-2)和3种剂量的60C o-γ射线辐射(100,150和200 Gy)处理4份大豆干种子,在相同种植条件下对其M6代产量性状和品质进行研究,比较2种处理方法对大豆产量性状及品质的诱变效应.结果表明:与对照相比,新大豆3号4×1016N+·cm-2离子束注入处理单株荚数显著增加,6×1016N+ ·cm-2离子束注入处理产量极显著增加;合99-756 8×1016 N+ ·cm-2离子束注入处理单株粒

  13. Underlying role of mechanical rigidity and topological constraints in physical sputtering and reactive ion etching of amorphous materials

    Science.gov (United States)

    Bhattarai, Gyanendra; Dhungana, Shailesh; Nordell, Bradley J.; Caruso, Anthony N.; Paquette, Michelle M.; Lanford, William A.; King, Sean W.

    2018-05-01

    Analytical expressions describing ion-induced sputter or etch processes generally relate the sputter yield to the surface atomic binding energy (Usb) for the target material. While straightforward to measure for the crystalline elemental solids, Usb is more complicated to establish for amorphous and multielement materials due to composition-driven variations and incongruent sublimation. In this regard, we show that for amorphous multielement materials, the ion-driven yield can instead be better understood via a consideration of mechanical rigidity and network topology. We first demonstrate a direct relationship between Usb, bulk modulus, and ion sputter yield for the elements, and then subsequently prove our hypothesis for amorphous multielement compounds by demonstrating that the same relationships exist between the reactive ion etch (RIE) rate and nanoindentation Young's modulus for a series of a -Si Nx :H and a -Si OxCy :H thin films. The impact of network topology is further revealed via application of the Phillips-Thorpe theory of topological constraints, which directly relates the Young's modulus to the mean atomic coordination () for an amorphous solid. The combined analysis allows the trends and plateaus in the RIE rate to be ultimately reinterpreted in terms of the atomic structure of the target material through a consideration of . These findings establish the important underlying role of mechanical rigidity and network topology in ion-solid interactions and provide additional considerations for the design and optimization of radiation-hard materials in nuclear and outer space environments.

  14. A fast beam-ion instability

    Energy Technology Data Exchange (ETDEWEB)

    Stupakov, G V [Stanford Linear Accelerator Center, Menlo Park, CA (United States)

    1996-08-01

    The ionization of residual gas by an electron beam in an accelerator generates ions that can resonantly couple to the beam through a wave propagating in the beam-ion system. Results of the study of a beam-ion instability are presented for a multi-bunch train taking into account the decoherence of ion oscillations due to the ion frequency spread and spatial variation of the ion frequency. It is shown that the combination of both effects can substantially reduce the growth rate of the instability. (author)

  15. Water Ice Radiolytic O2, H2, and H2O2 Yields for Any Projectile Species, Energy, or Temperature: A Model for Icy Astrophysical Bodies

    Science.gov (United States)

    Teolis, B. D.; Plainaki, C.; Cassidy, T. A.; Raut, U.

    2017-10-01

    O2, H2, and H2O2 radiolysis from water ice is pervasive on icy astrophysical bodies, but the lack of a self-consistent, quantitative model of the yields of these water products versus irradiation projectile species and energy has been an obstacle to estimating the radiolytic oxidant sources to the surfaces and exospheres of these objects. A major challenge is the wide variation of O2 radiolysis yields between laboratory experiments, ranging over 4 orders of magnitude from 5 × 10-7 to 5 × 10-3 molecules/eV for different particles and energies. We revisit decades of laboratory data to solve this long-standing puzzle, finding an inverse projectile range dependence in the O2 yields, due to preferential O2 formation from an 30 Å thick oxygenated surface layer. Highly penetrating projectile ions and electrons with ranges ≳30 Å are therefore less efficient at producing O2 than slow/heavy ions and low-energy electrons (≲ 400 eV) which deposit most energy near the surface. Unlike O2, the H2O2 yields from penetrating projectiles fall within a comparatively narrow range of (0.1-6) × 10-3 molecules/eV and do not depend on range, suggesting that H2O2 forms deep in the ice uniformly along the projectile track, e.g., by reactions of OH radicals. We develop an analytical model for O2, H2, and H2O2 yields from pure water ice for electrons and singly charged ions of any mass and energy and apply the model to estimate possible O2 source rates on several icy satellites. The yields are upper limits for icy bodies on which surface impurities may be present.

  16. Air ions and aerosol science

    International Nuclear Information System (INIS)

    Tammet, H.

    1996-01-01

    Collaboration between Gas Discharge and Plasma Physics, Atmospheric Electricity, and Aerosol Science is a factor of success in the research of air ions. The concept of air ion as of any carrier of electrical current through the air is inherent to Atmospheric Electricity under which a considerable statistical information about the air ion mobility spectrum is collected. A new model of air ion size-mobility correlation has been developed proceeding from Aerosol Science and joining the methods of neighboring research fields. The predicted temperature variation of the mobility disagrees with the commonly used Langevin rule for the reduction of air ion mobilities to the standard conditions. Concurrent errors are too big to be neglected in applications. The critical diameter distinguishing cluster ions and charged aerosol particles has been estimated to be 1.4 endash 1.8 nm. copyright 1996 American Institute of Physics

  17. Ion Colliders

    CERN Document Server

    Fischer, W

    2014-01-01

    High-energy ion colliders are large research tools in nuclear physics to study the Quark-Gluon-Plasma (QGP). The range of collision energy and high luminosity are important design and operational considerations. The experiments also expect flexibility with frequent changes in the collision energy, detector fields, and ion species. Ion species range from protons, including polarized protons in RHIC, to heavy nuclei like gold, lead and uranium. Asymmetric collision combinations (e.g. protons against heavy ions) are also essential. For the creation, acceleration, and storage of bright intense ion beams, limits are set by space charge, charge change, and intrabeam scattering effects, as well as beam losses due to a variety of other phenomena. Currently, there are two operating ion colliders, the Relativistic Heavy Ion Collider (RHIC) at BNL, and the Large Hadron Collider (LHC) at CERN.

  18. Recoil ions

    International Nuclear Information System (INIS)

    Cocke, C.L.; Olson, R.E.

    1991-01-01

    The collision of a fast moving heavy ion with a neutral atomic target can produce very highly charged but slowly moving target ions. This article reviews experimental and theoretical work on the production and use of recoil ions beyond the second ionization state by beams with specific energies above 0.5 MeV/amu. A brief historical survey is followed by a discussion of theoretical approaches to the problem of the removal of many electrons from a neutral target by a rapid, multiply charged projectile. A discussion of experimental techniques and results for total and differential cross sections for multiple ionization of atomic and molecular targets is given. Measurements of recoil energy are discussed. The uses of recoil ions for in situ spectroscopy of multiply charged ions, for external beams of slow, highly charged ions and in ion traps are reviewed. Some possible future opportunities are discussed. (orig.)

  19. A note on hypoplastic yielding

    OpenAIRE

    Nader, José Jorge

    2010-01-01

    This note discusses briefly the definition of yield surface in hypoplasticity in connection with the physical notion of yielding. The relation of yielding with the vanishing of the material time derivative of the stress tensor and the vanishing of the corotational stress rate is investigated.

  20. Implications of heavy-ion induced satellite x-ray emission. I. Introduction

    International Nuclear Information System (INIS)

    Raman, S.; Vane, C.R.

    1983-01-01

    Regardless of how they are induced, x-ray spectra are sensitive to the chemical environment of the emitting atom and can yield information on the atomic and electronic structure of host materials. Those spectra resulting from light ion and heavy ion excitations are the main topics covered in this series of papers. Highly energetic heavy ions are capable of producing multiple innershell ionization. The resulting spectrum of x-rays from a particular target atom is composed of a complex series of satellite lines. Environmental effects give rise to the redistribution of intensity from one satellite group to another. These changes can be correlated with one satellite group to another. These changes can be correlated with bulk chemical properties (valence electron densities, effective charges, covalencies, etc.). The possibility of obtaining new chemical information (for example, in implanted materials and in metal alloys) exists but requires greater experimental and theoretical understanding of both parametric variations and the fine structure of satellite lines

  1. Slowing down and straggling of protons and heavy ions in matter

    International Nuclear Information System (INIS)

    Aernsbergen, L.M. van.

    1986-01-01

    The Doppler Shift Attenuation (DSA) method is widely used to measure lifetimes of nuclear states. However, many of the lifetimes resulting from DSA measurements display large variations which are caused by an insufficient knowledge of slowing down processes of nucleus recoils. The measurement of 'ranges' is an often used method to study these slowing down processes. In this kind of measurement the distributions of implanted ions are determined for example by the method of Rutherford backscattering or from the yield curve of a resonant nuclear reaction. In this thesis, research on energy-loss processes of protons and Si ions in aluminium is presented. The so-called Resonance Shift method has been improved for the measurements on the protons themselves. This method has only been used occasionally before. A new method has been developed, which is called the Transmission Doppler Shift Attenuation (TDSA) method, for the measurement on Si ions. (Auth.)

  2. Ion Trap Quantum Computing

    Science.gov (United States)

    2011-12-01

    variations of ion traps, including (1) the cylindrically symmetric 3D ring trap; (2) the linear trap with a combination of cavity QED; (#) the symmetric...concepts of quantum information. The major demonstration has been the test of a Bell inequality as demonstrated by Rowe et al. [50] and a decoherence...famous physics experiment [62]. Wolfgang Paul demonstrated a similar apparatus during his Nobel Prize speech [63]. This device is hyperbolic- parabolic

  3. Influence of temperature on products yield of Eucalyptus microcorys carbonization

    Directory of Open Access Journals (Sweden)

    Renato da Silva Vieira

    2013-03-01

    Full Text Available During charcoal production different products are formed. These products are influenced primarily by the temperature of carbonization. Given that charcoal is the main input in the production of pig iron in Brazil, this study evaluated the influence of final temperature of carbonization of the products generated and also the influence of the radial and longitudinal sampling on the yield of each product. Samples were taken from internal and external position along the radius and also from three different heights from four Eucalyptus microcorys trees. The samples were carbonized in an electric furnace with an experimental water-cooled condenser and a collecting bottle of condensable volatile materials. The final temperatures of carbonization were 500, 600, 700, 800 and 900°C. The gravimetric yield, tar and non-condensable gases were calculated. The results showed no difference in the gravimetric yield in the longitudinal and radial positions studied, while the tar yield and non-condensable gases showed temperature variations of 700°C and 800°C and the variation of the gravimetric yield temperatures between 500°C to 900°C was 15%, the change of yield of tar from the radial direction of sampling was on average 8%, the variation of the yield of non-condensable gases in a radial sampling was on average 16%.

  4. Variational principles

    CERN Document Server

    Moiseiwitsch, B L

    2004-01-01

    This graduate-level text's primary objective is to demonstrate the expression of the equations of the various branches of mathematical physics in the succinct and elegant form of variational principles (and thereby illuminate their interrelationship). Its related intentions are to show how variational principles may be employed to determine the discrete eigenvalues for stationary state problems and to illustrate how to find the values of quantities (such as the phase shifts) that arise in the theory of scattering. Chapter-by-chapter treatment consists of analytical dynamics; optics, wave mecha

  5. Synthetic Brassica napus L.: Development and Studies on Morphological Characters, Yield Attributes, and Yield

    Directory of Open Access Journals (Sweden)

    M. A. Malek

    2012-01-01

    Full Text Available Brassica napus was synthesized by hybridization between its diploid progenitor species B. rapa and B. oleracea followed by chromosome doubling. Cross with B. rapa as a female parent was only successful. Among three colchicine treatments (0.10, 0.15, and 0.20%, 0.15% gave the highest success (86% of chromosome doubling in the hybrids (AC; 2=19. Synthetic B. napus (AACC, 2=38 was identified with bigger petals, fertile pollens and seed setting. Synthetic B. napus had increased growth over parents and exhibited wider ranges with higher coefficients of variations than parents for morphological and yield contributing characters, and yield per plant. Siliqua length as well as beak length in synthetic B. napus was longer than those of the parents. Number of seeds per siliqua, 1000-seed weight and seed yield per plant in synthetic B. napus were higher than those of the parents. Although flowering time in synthetic B. napus was earlier than both parents, however the days to maturity was little higher over early maturing B. rapa parent. The synthesized B. napus has great potential to produce higher seed yield. Further screening and evaluation is needed for selection of desirable genotypes having improved yield contributing characters and higher seed yield.

  6. Ion colliders

    International Nuclear Information System (INIS)

    Fischer, W.

    2010-01-01

    Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions (77Asb1, 81Bou1). The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the

  7. Ion colliders

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, W.

    2011-12-01

    Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions [77Asb1, 81Bou1]. The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the

  8. Yield improvement of Kenyan sesame varieties

    International Nuclear Information System (INIS)

    Ayiecho, P.O.; Nyabundi, J.O.

    2001-01-01

    In an effort to improve the yield of Kenyan sesame cultivars the seeds of three cultivars, SPS SIK6, SIK 096 and SPS SIK 50/1 were subjected to 300Gy, 400Gy and 600Gy of gamma rays. A first batch of seeds were subjected to these treatments in March 1994 (Experiment I) while the second batch was treated in March 1995 (Experiment II). The M 1 , M 2 , M 3 and M 4 generations of experiment I and M 1 generation of Experiment II were raised at the University of Nairobi Dryland Research Field Station, Kibwezi from 1994 to 1996. The M 6 and M 7 generations of Experiment I and M 2 of Experiment II were raised at Siaya Farmer's Training Centre in 1997. The effects of radiation in M 1 generation were expressed in reduced and delayed seedling emergence, reduced plant height, sectorial deformed plants, delayed flowering and extremely low yield. There was increased variation in M 2 for most evaluated traits. Plants in M 2 and subsequent generations were scored for a number of yield related morphological traits and days to flowering. Selection was done in the early generations for increased capsule number and earliness. As a result of selection, a total of 88 lines from M 4 generation were used to derive M 5 generation. Further selection in M 6 generation lead to 35 lines being retained for preliminary yield trials in M 7 generations. (author)

  9. Recent negative ion source developments

    International Nuclear Information System (INIS)

    Alton, G.D.

    1978-01-01

    This report describes recent results obtained from studies associated with the development of negative ion sources which utilize sputtering in a diffuse cesium plasma as a means of ion beam generation. Data are presented which relate negative ion yield and important operational parameters such as cesium oven temperature and sputter probe voltage from each of the following sources: (1) A source based in principle according to the University of Aarhus design and (2) an axial geometry source. The important design aspects of the sources are given--along with a list of the negative ion intensities observed to date. Also a qualitative description and interpretation of the negative ion generation mechanism in sources which utilize sputtering in the presence of cesium is given

  10. Tin-containing silicates: Alkali salts improve methyl lactate yield from sugars

    DEFF Research Database (Denmark)

    Tolborg, Søren; Sádaba, Irantzu; Osmundsen, Christian Mårup

    2015-01-01

    This study focuses on increasing the selectivity to methyl lactate from sugars using stannosilicates as heterogeneous catalyst. All group I ions are found to have a promoting effect on the resulting methyl lactate yield. Besides, the alkali ions can be added both during the preparation of the cat......This study focuses on increasing the selectivity to methyl lactate from sugars using stannosilicates as heterogeneous catalyst. All group I ions are found to have a promoting effect on the resulting methyl lactate yield. Besides, the alkali ions can be added both during the preparation...

  11. Intense ion beams for inertial confinement fusion

    International Nuclear Information System (INIS)

    Mehlhorn, T.A.

    1997-01-01

    Intense beams of light of heavy ions are being studied as inertial confinement fusion (ICF) drivers for high yield and energy. Heavy and light ions have common interests in beam transport, targets, and alternative accelerators. Self-pinched transport is being jointly studied. This article reviews the development of intense ion beams for ICF. Light-ion drivers are highlighted because they are compact, modular, efficient and low cost. Issues facing light ions are: (1) decreasing beam divergence; (2) increasing beam brightness; and (3) demonstrating self-pinched transport. Applied-B ion diodes are favored because of efficiency, beam brightness, perceived scalability, achievable focal intensity, and multistage capability. A light-ion concept addressing these issues uses: (1) an injector divergence of ≤ 24 mrad at 9 MeV; (2) two-stage acceleration to reduce divergence to ≤ 12 mrad at 35 MeV; and (3) self-pinched transport accepting divergences up to 12 mrad. Substantial progress in ion-driven target physics and repetitive ion diode technology is also presented. Z-pinch drivers are being pursued as the shortest pulsed power path to target physics experiments and high-yield fusion. However, light ions remain the pulsed power ICF driver of choice for high-yield fusion energy applications that require driver standoff and repetitive operation. 100 refs

  12. Genetic basis of yield and some yield related traits in basmati rice

    International Nuclear Information System (INIS)

    Saleem, M.Y.; Haq, M.A.; Mirza, J.I.

    2010-01-01

    Additive, dominance and epistasis components of genetic variation for yield and some yield related traits were assessed through modified triple test cross technique in Basmati rice. Epistasis was found an important part of genetic variation for plant height, tillers per plant, secondary branches per panicle, grains per panicle, 1000-grain weight and yield per plant except primary branches per panicle and panicle length. Bifurcation of epistasis showed that additive x additive (i) type and additive x dominance + dominance x dominance (j + l) types of non-allelic interactions were involved in the expression of these traits. Additive and dominance type of gene action influenced the expression of primary branches per panicle and panicle length. No evidence of directional dominance was observed for these two traits. For plant height, tillers per plant, secondary branches per panicle, grains per panicle, 1000-grain weight and yield per plant, recurrent selection or bi parental mating may be exercised in F2 and following generations however, selection of desired plants may be postponed till F5 or F6 generations to permit maximum obsession of epistatic effects to develop desired cultivar(s) in Basmati rice.(author)

  13. Variational transition state theory

    International Nuclear Information System (INIS)

    Truhlar, D.G.

    1986-01-01

    This project is concerned with the development and applications of generalized transition state theory and multidimensional tunneling approximations to chemical reaction rates. They have developed and implemented several practical versions of variational transition state theory (VTST), namely canonical variational theory (CVT), improved canonical variational theory (ICVT), and microcanonical variational theory (μVT). They have also developed and implemented several accurate multidimensional semiclassical tunneling approximations, the most accurate of which are the small-curvature semiclassical adiabatic (SCSA), large-curvature version-3 (LC3), and least-action (LA) approximations. They have applied the methods to thermal rate constants, using transmission coefficients based on ground-state tunneling, and they have also presented and applied adiabatic and diabatic extensions to calculated rate constants for vibrationally excited reactants. Their general goal is to develop accurate methods for calculating chemical reaction rate constants that remain practical even for reasonably complicated molecules. The approximations mentioned above yield rate constants for systems whose potential energy surface is known or assumed. Thus a second, equally important aspect of their work is the determination or modeling, semi-empirically and/or from electronic structure calculations, of potential energy surfaces

  14. Correlation Between Precipitation and Crop Yield for Corn and Cotton Produced in Alabama

    Science.gov (United States)

    Hayes, Carol E.; Perkey, Donald J.

    1998-01-01

    In this study, variations in precipitation during the time of corn silking are compared to Alabama corn yields. Also, this study compares precipitation variations during bloom to Alabama cotton yield. The goal is to obtain mathematical correlations between rainfall during the crop's critical period and the crop amount harvested per acre.

  15. Systematics in delayed neutron yields

    Energy Technology Data Exchange (ETDEWEB)

    Ohsawa, Takaaki [Kinki Univ., Higashi-Osaka, Osaka (Japan). Atomic Energy Research Inst.

    1998-03-01

    An attempt was made to reproduce the systematic trend observed in the delayed neutron yields for actinides on the basis of the five-Gaussian representation of the fission yield together with available data sets for delayed neutron emission probability. It was found that systematic decrease in DNY for heavier actinides is mainly due to decrease of fission yields of precursors in the lighter side of the light fragment region. (author)

  16. VARIABILITY OF YIELD AND YIELD COMPONENTS IN “EGUSI ...

    African Journals Online (AJOL)

    journal

    Estimate of expected genetic advance in seed yield plant-1 ranged between. 25.90-48.40%. ..... values in fruit and seed yield characters have been reported in culinary melon, ... and Khund, A. 2004. Extent of heterosis and heritability in some.

  17. Response of Yield and Yield Components of Tef [Eragrostis Tef ...

    African Journals Online (AJOL)

    The partial budget analysis also indicates that applications of 46 kg. N ha-1 and 10 kg P ha-1 are ..... (1994) indicated that where the grain yield response is negative, yield reduction is primarily caused by a .... An Economic Training. Manual.

  18. On yield gaps and yield gains in intercropping

    NARCIS (Netherlands)

    Gou, Fang; Yin, Wen; Hong, Yu; Werf, van der Wopke; Chai, Qiang; Heerink, Nico; Ittersum, van Martin K.

    2017-01-01

    Wheat-maize relay intercropping has been widely used by farmers in northwest China, and based on field experiments agronomists report it has a higher productivity than sole crops. However, the yields from farmers’ fields have not been investigated yet. Yield gap analysis provides a framework to

  19. 7755 EFFECT OF NPK FERTILIZER ON FRUIT YIELD AND YIELD ...

    African Journals Online (AJOL)

    Win7Ent

    2013-06-03

    Jun 3, 2013 ... peasant farmers in Nigeria. With the increased ... did not significantly (p=0.05) increase the fruit yield nor the seed yield. Key words: NPK fertilizer, Fruit ..... SAS (Statistical Analysis System) Version 9.1. SAS Institute Inc., Cary, ...

  20. SLIFER measurement for explosive yield

    International Nuclear Information System (INIS)

    Bass, R.C.; Benjamin, B.C.; Miller, H.M.; Breding, D.R.

    1976-04-01

    This report describes the shorted location indicator by frequency of electrical resonance (SLIFER) system used at Sandia Laboratories for determination of explosive yield of under ground nuclear tests

  1. Sputtering on cobalt with noble gas ions

    International Nuclear Information System (INIS)

    Sarholt-Kristensen, L.; Johansen, A.; Johnson, E.

    1983-01-01

    Single crystals of cobalt have been bombarded with 80 keV Ar + ions and with 80 keV and 200 keV Xe + ions in the [0001] direction of the hcp phase and the [111] direction of the fcc phase. The sputtering yield has been measured as function of target temperature (20 0 C-500 0 C), showing a reduction in sputtering yield for 80 keV Ar + ions and 200 keV Xe + ions, when the crystal structure changes from hcp to fcc. In contrast to this, bombardment with 80 keV Xe + ions results in an increase in sputtering yield as the phase transition is passed. Sputtering yields for [111] nickel are in agreement with the sputtering yields for fcc cobalt indicating normal behaviour of the fcc cobalt phase. The higher sputtering yield of [0001] cobalt for certain combinations of ion mass and energy may then be ascribed to disorder induced partly by martensitic phase transformation, partly by radiation damage. (orig.)

  2. ion irradiation

    Indian Academy of Sciences (India)

    Swift heavy ions interact predominantly through inelastic scattering while traversing any polymer medium and produce excited/ionized atoms. Here samples of the polycarbonate Makrofol of approximate thickness 20 m, spin coated on GaAs substrate were irradiated with 50 MeV Li ion (+3 charge state). Build-in ...

  3. Ion microprobes

    International Nuclear Information System (INIS)

    Coles, J.N.; Long, J.V.P.

    1977-01-01

    An ion microprobe is described that has an ion extraction arrangement comprising two separate paths for ions and electrons diverging from a common point. A cone shaped or pyramidal guard electrode surrounds each path the apex angles being equal and coinciding with the said point. The guard electrodes are positioned to lie tangentially to each other and to a planar surface including the said point. An aperture is provided for the two paths at the apexes of both guard electrodes, and electrical connections between the guard electrodes enable the same potential to be applied to both guard electrodes. Means are provided for generating oppositely polarised electric fields within the guard electrodes, together with means for causing a focused ion beam to strike the common point without suffering astigmatism. The means for causing a focused ion beam to strike the said point includes an ion gun for directing an ion beam along one of the paths and means to provide an axial accelerating field there along. Optical viewing means are also provided. Existing designs enable only ions or electrons, but not both, to be extracted at any one time. (U.K.)

  4. Photoconductivity studies of the ferrocyanide ion under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Finston, M. I.

    1979-01-01

    The photoaquation of the ferrocyanide ion was studied using a high-pressure photoconductivity apparatus and a steady-state high-pressure mercury lamp. The first-order photocurrent rise-time could be related to the relative quantum efficiency of the photoaquation process, while the dark decay of the photocurrent yielded a relative value of the bimolecular rate-constant for the reverse reaction. Kinetic measurements were carried out on dilute solutions of potassium ferrocyanide in pure water, and in 20% ethanol. The photocurrent yield in aqueous solution was dependent upon secondary chemical equilibria which were sensitive to pressure in a predictable way. In ethanolic solution, the dependence of photocurrent yield on pressure followed the variation of the reciprocal solvent vicosity. In both aqueous and alcoholic solution, the photoaquation quantum efficiency decreased exponentially with pressure, as did the biomolecular rate-constant for the dark reaction in aqueous solution. The pressure dependence of the bimolecular rate-constant in the alcoholic solution indicated a diffusion-limited process. The pressure dependence of the photoaquation quantum yield, and of the bimolecular rate-constant in aqueous solution, was interpreted in terms of an activation volume model. The photoaquation data for both the aqueous and the alcoholic solutions agreed with a hypothetical mechanism whereby ligand-to-metal bond-breaking, and solvent-to-metal bond-formation, are effectively simultaneous. The results for the aqueous dark reaction strongly indicated breaking of the solvent-to-metal bond as the rate-limiting step.

  5. Uso de modelos de regressão aleatória para descrever a variação genética da produção de leite na raça Holandesa Random regressions models to describe the genetic variation of milk yield in Holstein breed

    Directory of Open Access Journals (Sweden)

    Cláudio Vieira de Araújo

    2006-06-01

    . The Wilmink's exponential function, the Ali and Schaeffer logarithmic function and the Legendre orthogonal polynomials of second and fourth order were used. The comparisons among the models were based on the following criteria: estimates of variance components of the multiple-trait model and random regressions models, values of residual variance and values of the logarithms of the likelihood functions. The heritability estimates obtained using the multiple-trait model varied from 0.110 to 0.244, for the random regression models the values ranged from 0.127 to 0.301, being the largest estimates observed in the models with larger number of parameters. The random regression models which used the Legendre polynomials was the model which better described the genetic variation of the milk yield.

  6. Super TOF secondary ion mass spectroscopy using very highly charged primary ions up to Th70+

    International Nuclear Information System (INIS)

    Briere, M.A.; Schenkel, T.; Schneider, D.

    1995-01-01

    The LLNL Electron Beam Ion Trap (EBIT) has made low emittance beams of slow highly charged ions available for ion-solid interaction studies. Such interactions feature the dominance of electronic over collisional effects, and the shock waves generated by the ionized target atoms can desorb large numbers of large molecular species from the surface. This paper presents the first systematic study of the sputtering process due to the incidence of slow very highly charged ions; Th 70+ ions are extracted from EBIT at 7 keV * q and directed onto thin SiO 2 films on Si. Results suggest secondary ion yields of up to 25 per incident ion for Th 70+ (secondary ion yield is increased over that for singly or moderately charged ions). Correlations of the negative, positive, and negative cluster ion yields show promise for application of highly charged ion induced sputtering for enhanced sensitivity and quantitative (absolute) SIMS analysis of deep submicron scale surface layers and polymeric and biomolecular material analysis

  7. Ethiopian Wheat Yield and Yield Gap Estimation: A Spatial Small Area Integrated Data Approach

    Science.gov (United States)

    Mann, M.; Warner, J.

    2015-12-01

    Despite the collection of routine annual agricultural surveys and significant advances in GIS and remote sensing products, little econometric research has been undertaken in predicting developing nation's agricultural yields. In this paper, we explore the determinants of wheat output per hectare in Ethiopia during the 2011-2013 Meher crop seasons aggregated to the woreda administrative area. Using a panel data approach, combining national agricultural field surveys with relevant GIS and remote sensing products, the model explains nearly 40% of the total variation in wheat output per hectare across the country. The model also identifies specific contributors to wheat yields that include farm management techniques (eg. area planted, improved seed, fertilizer, irrigation), weather (eg. rainfall), water availability (vegetation and moisture deficit indexes) and policy intervention. Our findings suggest that woredas produce between 9.8 and 86.5% of their potential wheat output per hectare given their altitude, weather conditions, terrain, and plant health. At the median, Amhara, Oromiya, SNNP, and Tigray produce 48.6, 51.5, 49.7, and 61.3% of their local attainable yields, respectively. This research has a broad range of applications, especially from a public policy perspective: identifying causes of yield fluctuations, remotely evaluating larger agricultural intervention packages, and analyzing relative yield potential. Overall, the combination of field surveys with spatial data can be used to identify management priorities for improving production at a variety of administrative levels.

  8. Photoionization of FE3+ Ions

    International Nuclear Information System (INIS)

    Ovchinnikov, O.; Schlachter, F.

    2003-01-01

    Photoionization of Fe3+ ions was studied for the first time using synchrotron radiation from the Advanced Light Source (ALS) and the merged-beams technique. Fe3+ ions were successfully produced using ferrocene in an electron cyclotron resonance ion source (ECR). The measured yield of Fe4+ photoions as a function of photon energy revealed the presence of resonances that correspond to excitation of autoionizing states. These resonances are superimposed upon the photoion yield produced by direct photoionization, which is a smooth, slowly decreasing function of energy. The spectra for the photoionization of Fe3+ will be analyzed and compared with theory. The data collected will also serve to test models for the propagation of light through ionized matter.

  9. High yielding mutants of blackgram variety 'PH-25'

    International Nuclear Information System (INIS)

    Misra, R.C.; Mohapatra, B.D.; Panda, B.S.

    2001-01-01

    Seeds of blackgram (Vigna mungo L.) variety 'PH-5' were treated with chemical mutagens ethyl methanesulfonate (EMS), nitrosoguanidine (NG), maleic hydrazide (MH) and sodium azide (NaN 3 ), each at 3 different concentrations. Thirty six mutant lines developed from mutagenic treatments along with parent varieties were tested in M 4 generation. The mutants showed wide variation in most of the traits and multivariante D 2 analysis showed genetic divergence among themselves. Twenty of the thirty mutants showed genetic divergence from parent. Ten selected high yielding mutants were tested in M 5 . Yield and other productive traits of five high yielding mutants in M 4 and M 5 are presented

  10. Isotope yield ratios as a probe of the reaction dynamics

    International Nuclear Information System (INIS)

    Trautmann, W.; Hildenbrand, K.D.; Lynen, U.; Mueller, W.F.J.; Rabe, H.J.; Sann, H.; Stelzer, H.; Trockel, R.; Wada, R.; Brummund, N.; Glasow, R.; Kampert, K.H.; Santo, R.; Eckert, E.M.; Pochodzalla, J.; Bock, I.; Pelte, D.

    1987-04-01

    Isotopically resolved yields of particles and complex fragments from 12 C and 18 O induced reactions on 53 Ni, 54 Ni, Ag, and 197 Au in the intermediate range of bombarding energies 30 MeV ≤ E/A ≤ 84 MeV were measured. The systematic variation of the deduced isotope yield ratios with projectile and target is used to determine the degree of N/Z equilibration achieved and to establish time scales for the reaction process. A quantum statistical model is employed in order to derive entropies of the emitting systems from the measured isotope yield ratios. (orig.)

  11. Ion implantation

    International Nuclear Information System (INIS)

    Johnson, E.

    1986-01-01

    It is the purpose of the present paper to give a review of surface alloy processing by ion implantation. However, rather than covering this vast subject as a whole, the survey is confined to a presentation of the microstructures that can be found in metal surfaces after ion implantation. The presentation is limited to alloys processed by ion implantation proper, that is to processes in which the alloy compositions are altered significantly by direct injection of the implanted ions. The review is introduced by a presentation of the processes taking place during development of the fundamental event in ion implantation - the collision cascade, followed by a summary of the various microstructures which can be formed after ion implantation into metals. This is compared with the variability of microstructures that can be achieved by rapid solidification processing. The microstructures are subsequently discussed in the light of the processes which, as the implantations proceed, take place during and immediately after formation of the individual collision cascades. These collision cascades define the volumes inside which individual ions are slowed down in the implanted targets. They are not only centres for vigorous agitation but also the sources for formation of excess concentrations of point defects, which will influence development of particular microstructures. A final section presents a selection of specific structures which have been observed in different alloy systems. (orig./GSCH)

  12. Metaleptic Variations

    OpenAIRE

    Pernot, Dominique

    2014-01-01

    Les derniers romans de Gabriel Josipovici offrent beaucoup de variété, allant de la parodie, de la fiction comique légère, dans Only Joking et Making Mistakes, à des sujets plus graves, plus personnels, ontologiques. Dans un court roman, Everything Passes, et dans un roman majeur, Goldberg: Variations, le lecteur est amené à se poser des questions sur la nature mystérieuse de la réalité, qui est, trop souvent, acceptée sans conteste par de nombreux roma...

  13. Interaction of slow and highly charged ions with surfaces: formation of hollow atoms

    Energy Technology Data Exchange (ETDEWEB)

    Stolterfoht, N; Grether, M; Spieler, A; Niemann, D [Hahn-Meitner Institut, Berlin (Germany). Bereich Festkoerperphysik; Arnau, A

    1997-03-01

    The method of Auger spectroscopy was used to study the interaction of highly charged ions with Al and C surfaces. The formation of hollow Ne atoms in the first surface layers was evaluated by means of a Density Functional theory including non-linear screening effects. The time-dependent filling of the hollow atom was determined from a cascade model yielding information about the structure of the K-Auger spectra. Variation of total intensities of the L- and K-Auger peaks were interpreted by the cascade model in terms of attenuation effects on the electrons in the solid. (author)

  14. Nitrogen rate and plant population effects on yield and yield ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-17

    Gan et al., 2003). Nitrogen increases yield by influencing a variety of agronomic and quality parameters. In general, there was an increase in plant height and dry matter accumulation per plant in soybean (Manral and Saxena, ...

  15. Nitrogen rate and plant population effects on yield and yield ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-17

    Dec 17, 2008 ... density and nitrogen rate increased plant height, lowest pod height, harvest index and seed yield. ... since some combine harvester heads are unable to pick ..... as effected by population density and plant distribution.

  16. Decadal variations in groundwater quality

    DEFF Research Database (Denmark)

    Jessen, Søren; Postma, Dieke; Thorling, Lærke

    2017-01-01

    Twenty-five years of groundwater quality monitoring in a sandy aquifer beneath agricultural fields showed large temporal and spatial variations in major ion groundwater chemistry, which were linked closely to the nitrate (NO3) content of agricultural recharge. Between 1988 and 2013, the NO3 content...... of water in the oxidized zone of the aquifer nearly halved, following implementation of action plans to reduce N leaching from agriculture. However, due to denitrification by pyrite oxidation in the aquifer, a plume of sulfate-rich water migrates through the aquifer as a legacy of the historical NO3...... loading. Agriculture thus is an important determinant of major ion groundwater chemistry. Temporal and spatial variations in the groundwater quality were simulated using a 2D reactive transport model, which combined effects of the historical NO3 leaching and denitrification, with dispersive mixing...

  17. Heavy-ion radiation chemistry

    International Nuclear Information System (INIS)

    Imamura, Masashi

    1975-01-01

    New aspect of heavy ion radiation chemistry is reviewed. Experiment has been carried out with carbon ions and nitrogen ions accelerated by a 160 cm cyclotron of the Institute of Physical and Chemical Research. The results of experiments are discussed, taking into consideration the effects of core radius depending on heavy ion energy and of the branch tracks of secondary electrons outside the core on chemical reaction and the yield of products. The effect of core size on chemical reaction was not able to be observed, because the incident energy of heavy ions was only several tens of MeV. Regarding high radical density, attention must be given to the production of oxygen in the core. It is possible to produce O 2 in the core in case of high linear energy transfer (LET), while no production of O 2 in case of low LET radiation. This may be one of study problems in future. LET effects on the yield of decomposed products were examined on acetone, methyl-ethyl-ketone and diethyl ketone, using heavy ions (C and N) as well as gamma radiation and helium ions. These three ketones showed that the LET change of two gaseous products, H 2 and CO, was THF type. There are peaks at 50-70 eV/A in the yield of both products. The peaks suggest the occurrence of ''saturation'' in decomposition. Attention was drawn to acetone containing a small amount (2 wt.%) of H 2 O. H 2 O and CO produced from this system differ from those in the pure system. The hydrogen connection formed by such a small amount of H 2 O may mediate the energy transfer. Sodium acetate tri-hydrate produces CH 3 radical selectively by gamma-ray irradiation at 77 K. In this case, the production of CH 2 COO - increases with the increase of LET of radiation. This phenomenon may be an important study problem. (Iwakiri, K.)

  18. Somaclonal variation in rice

    International Nuclear Information System (INIS)

    Kucherenko, L.

    1990-01-01

    Full text: 32 varieties of Oryza sativa L. ssp. japonica were used as donors for callus induction from somatic tissues. In some cases, the callus was treated before regeneration with the chemical mutagen MNU. Some of the regenerated plants demonstrated heritable alterations, among them chlorophyll deficiencies, variation in plant height, awness, glume colouring and fertility. Along with these, a number of lines with agronomically valuable alterations concerning maturity time, panicle structure, plant productivity and grain quality were found. The spectrum of variability was very wide. Vivipary was noticed. Superdwarfs with plant height of about 15 cm were found. Plants with no visible distinctions could be variants too, for example, with increased protein content or disease resistance. The rate and the spectrum of the somaclonal variation were not influenced by the culture media but depended on the donor's genotype. On the basis of somaclonal variation a variety 'Bioryza' was developed. It is an early maturing (about 95-100 days), long grain variety, with grain yield up to 8 t/ha. (author)

  19. Ion scattering studies of ordered alloy surfaces: CuAu(1 0 0) and NiAl

    International Nuclear Information System (INIS)

    Beikler, R.; Taglauer, E.

    2000-01-01

    The composition and structure of alloy surfaces can differ from the corresponding bulk properties due to segregation and relaxation effects. We studied the (1 0 0) surface of the ordered alloy CuAu and amorphous Ni and Al by low-energy Ne + and Na + ion scattering. The interpretation of the experimental results is supported by numerical simulations using the MARLOWE code. In the CuAu system a certain geometry was found to be very sensitive to Au presence in the 2nd layer. Comparison with MARLOWE results also allows to study variations in the ion yields arising from neutralization effects. By trajectory analysis ion survival probabilities are estimated for Ni and Al

  20. Physics of ion sputtering

    International Nuclear Information System (INIS)

    Robinson, M.T.

    1984-04-01

    The ejection of atoms by the ion bombardment of solids is discussed in terms of linear collision cascade theory. A simple argument describes the energies of the ejecta, but elaborate models are required to obtain accurate sputtering yields and related quantities. These include transport theoretical models based on linearized Boltzmann equations, computer simulation models based on the binary collision approximation, and classical many-body dynamical models. The role of each kind of model is discussed. Several aspects of sputtering are illustrated by results from the simulation code MARLOWE. 20 references, 6 figures

  1. Nanostructuring by ion beam

    International Nuclear Information System (INIS)

    Valbusa, U.; Boragno, C.; Buatier de Mongeot, F.

    2003-01-01

    In metals, the surface curvature dependence of the sputtering yield and the presence of an extra energy barrier whenever diffusing adatoms try to descend step edges, produce a similar surface instability, which builds up regular patterns. By tuning the competition between these two mechanisms, it is possible to create self-organized structures of the size of few nanometers. Height, lateral distance and order of the structures change with the deposition parameters like ion energy, dose, incident angle and substrate temperature. The paper offers an overview of the experiments carried out and foresees possible applications of these results in the area of material science

  2. CO2 laser photolysis of clustered ions, (1)

    International Nuclear Information System (INIS)

    Ikezoe, Yasumasa; Soga, Takeshi; Suzuki, Kazuya; Ohno, Shin-ichi.

    1990-09-01

    Vibrational excitation and the following decomposition of cluster ions by CO 2 laser photons are studied. Characteristics of the cluster ion and the CO 2 laser photon are summarized in their relation to the photolysis of cluster ions. An apparatus was installed, which is composed of (1) corona discharge-jet expansion section (formation of cluster ions), (2) CO 2 laser section (photolysis of cluster ions), and (3) mass spectrometer section. Experimental results of ammonia cluster ions were described. Effects of repeller voltage, shape of repellers, and adiabatic cooling are examined on the formation of ammonia cluster ions by corona discharge-jet expansion method. Collisional dissociation of cluster ions was observed at high repeller voltages. Size distribution of the ammonia cluster ion is discussed in connection with the temperature of cluster ions. Intensity of CO 2 laser was related to decomposition yield of cluster ions. (author)

  3. Understanding the weather signal in national crop-yield variability

    Science.gov (United States)

    Frieler, Katja; Schauberger, Bernhard; Arneth, Almut; Balkovič, Juraj; Chryssanthacopoulos, James; Deryng, Delphine; Elliott, Joshua; Folberth, Christian; Khabarov, Nikolay; Müller, Christoph; Olin, Stefan; Pugh, Thomas A. M.; Schaphoff, Sibyll; Schewe, Jacob; Schmid, Erwin; Warszawski, Lila; Levermann, Anders

    2017-06-01

    Year-to-year variations in crop yields can have major impacts on the livelihoods of subsistence farmers and may trigger significant global price fluctuations, with severe consequences for people in developing countries. Fluctuations can be induced by weather conditions, management decisions, weeds, diseases, and pests. Although an explicit quantification and deeper understanding of weather-induced crop-yield variability is essential for adaptation strategies, so far it has only been addressed by empirical models. Here, we provide conservative estimates of the fraction of reported national yield variabilities that can be attributed to weather by state-of-the-art, process-based crop model simulations. We find that observed weather variations can explain more than 50% of the variability in wheat yields in Australia, Canada, Spain, Hungary, and Romania. For maize, weather sensitivities exceed 50% in seven countries, including the United States. The explained variance exceeds 50% for rice in Japan and South Korea and for soy in Argentina. Avoiding water stress by simulating yields assuming full irrigation shows that water limitation is a major driver of the observed variations in most of these countries. Identifying the mechanisms leading to crop-yield fluctuations is not only fundamental for dampening fluctuations, but is also important in the context of the debate on the attribution of loss and damage to climate change. Since process-based crop models not only account for weather influences on crop yields, but also provide options to represent human-management measures, they could become essential tools for differentiating these drivers, and for exploring options to reduce future yield fluctuations.

  4. Vacuum Technology for Ion Sources

    International Nuclear Information System (INIS)

    Chiggiato, P

    2013-01-01

    The basic notions of vacuum technology for ion sources are presented, with emphasis on pressure profile calculation and choice of pumping technique. A Monte Carlo code (Molflow+) for the evaluation of conductances and the vacuum-electrical analogy for the calculation of time-dependent pressure variations are introduced. The specific case of the Linac4 H - source is reviewed. (author)

  5. Sputtering of solid deuterium by He-ions

    DEFF Research Database (Denmark)

    Schou, Jørgen; Stenum, B.; Pedrys, R.

    2001-01-01

    Sputtering of solid deuterium by bombardment of 3He+ and 4He+ ions was studied. Some features are similar to hydrogen ion bombardment of solid deuterium, but for the He-ions a significant contribution of elastic processes to the total yield can be identified. The thin-film enhancement is more pro...... pronounced than that for hydrogen projectiles in the same energy range....

  6. Teaching SIMS fundamentals using the FIB ion microscope

    International Nuclear Information System (INIS)

    Chater, Richard J.; McPhail, David S.

    2008-01-01

    The use of liquid metal source ion beams for microscopy and ion milling applications has increased dramatically in recent years. This paper explores the teaching of ion-solid sputtering and ionization phenomena without the facility to mass analyse the ionised yield available in dedicated SIMS instrumentation. Fundamental parameters can be demonstrated during the limited period of an undergraduate laboratory teaching session

  7. Investigation of branching of bromine in latent ion traces

    International Nuclear Information System (INIS)

    Vareille, J.C.; Moliton, J.P.; Decossas, J.L.; Teyssier, J.L.; Delaunay, B.

    1981-01-01

    We show that the branching of bromide atoms is possible on chemically active sites produced by Kr 8+ , Cl 6+ and He 2+ ion irradiation on cellulose triacetate. The number of fixed atoms increases with ion fluence and atomic number. These results are in good agreement with those concerning radical yield around the ions' path. (orig.)

  8. Determination of moisture content in steams and variation in moisture content with operating boiler level by analyzing sodium content in steam generator water and steam condensate of a nuclear power plant using ion chromatographic technique

    International Nuclear Information System (INIS)

    Pal, P.K.; Bohra, R.C.

    2015-01-01

    Dry steam with moisture content less than <1% is the stringent requirements in a steam generator for good health of the turbine. In order to confirm the same, determination of sodium is done in steam generator water and steam condensate using Flame photometer in ppm level and ion chromatograph in ppb level. Depending on the carry over of sodium in steam along with the water droplet (moisture), the moisture content in steam was calculated and was found to be < 1% which is requirements of the system. The paper described the salient features of a PHWR, principle of Ion Chromatography, chemistry parameters of Steam Generators and calculation of moisture content in steam on the basis of sodium analysis. (author)

  9. Superconducting ECR ion source system

    International Nuclear Information System (INIS)

    Sharma, S.C.; Gore, J.A.; Gupta, A.K.; Saxena, A.

    2017-01-01

    In order to cover the entire mass range of the elements across the periodic table, an ECR based heavy ion accelerator programme, consisting of a superconducting ECR (Electron Cyclotron Resonance) source and a room temperature RFQ (Radio Frequency Quadrupole) followed by low and high beta superconducting resonator cavities has been proposed. The 18 GHz superconducting ECR ion source system has already been commissioned and being operated periodically at FOTIA beam hall. This source is capable of delivering ion beams right from proton to uranium with high currents and high charge states over a wide mass range (1/7 ≤ q/m ≤ 1/2) across the periodic table, including U"3"4"+ (q/m∼1/7) with 100 pna yield. The normalized transverse beam emittance from ECR source is expected to be <1.0 pi mm mrad. ECR ion sources are quite robust, making them suitable for operating for weeks continuously without any interruption

  10. A logging residue "yield" table for Appalachian hardwoods

    Science.gov (United States)

    A. Jeff Martin

    1976-01-01

    An equation for predicting logging-residue volume per acre for Appalachian hardwoods was developed from data collected on 20 timber sales in national forests in West Virginia and Virginia. The independent variables of type-of-cut, products removed, basal area per acre, and stand age explained 95 percent of the variation in residue volume per acre. A "yield"...

  11. Determination of the yield locus by means of temperature measurement

    NARCIS (Netherlands)

    Banabic, D.; Huetink, Han

    2006-01-01

    The paper presents a theoretical background of the thermo-graphical method of determining the yield locus. The analytical expression of the temperature variation of the specimen deformed in the elastic state is determined starting from the first law of thermodynamics. The experimental method for

  12. Growth, assimilate partitioning and grain yield response of soybean ...

    African Journals Online (AJOL)

    This investigation tested variation in the growth components, assimilate partitioning and grain yield of soybean (Glycine max L. Merrrill) varieties established in CO2 enriched atmosphere when inoculated with mixtures of Arbuscular mycorrhizal fungi (AMF) species in the humid rainforest of Nigeria. A pot and a field ...

  13. Evaluation of polycross sweetpotato seedlings for root yield potential ...

    African Journals Online (AJOL)

    The study aimed at determining the root yield potential of the sweetpotato seedlings, the variation in storage root flesh colour and response of the storage roots to major pests and diseases attacking sweetpotato in the field .The experiment was carried out in the screen house and at the Eastern experimental field of National ...

  14. GANIL Workshop on Ion Sources; Journees Sources d'Ions

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, Renan [Grand Accelerateur National d' Ions Lourds (GANIL), 14 - Caen (France)

    1999-07-01

    The proceedings of the GANIL Workshop on Ion Sources held at GANIL - Caen on 18-19 March 1999 contains 13 papers aiming at improving the old source operation and developing new types of sources for nuclear research and studies of ion physics. A number of reports are devoted to applications like surface treatment, ion implantation or fusion injection. The 1+{yields}n+ transformation, charged particle transport in ECR sources, addition of cesium and xenon in negative ion sources and other basic issues in ion sources are also addressed.

  15. Experiencing variation

    DEFF Research Database (Denmark)

    Kobayashi, Sofie; Berge, Maria; Grout, Brian William Wilson

    2017-01-01

    This study contributes towards a better understanding of learning dynamics in doctoral supervision by analysing how learning opportunities are created in the interaction between supervisors and PhD students, using the notion of experiencing variation as a key to learning. Empirically, we have based...... the study on four video-recorded sessions, with four different PhD students and their supervisors, all from life sciences. Our analysis revealed that learning opportunities in the supervision sessions concerned either the content matter of research (for instance, understanding soil structure......), or the research methods— more specifically how to produce valid results. Our results illustrate how supervisors and PhD students create a space of learning together in their particular discipline by varying critical aspects of their research in their discussions. Situations where more openended research issues...

  16. Genetic variation and trait correlations in a birdresistant pearl millet ...

    African Journals Online (AJOL)

    selection indices for effective improvement. There was significant genetic variation for grain yield and most yield component traits, indicating that selection within the population would be feasible. Genetic variation was, however not significant for the percent incidence of downy mildew, implying that selection for improving ...

  17. Extended incident-angle dependence formula of sputter yield

    International Nuclear Information System (INIS)

    Ono, T.; Shibata, K.; Muramoto, T.; Kenmotsu, T.; Li Z.; Kawamura, T.

    2006-06-01

    We extend a new semi-empirical formula for incident-angle dependence of normalized sputter yield that includes the contribution to sputter yield from the direct knock-out process that was not considered in the previously proposed one. Three parameters included in the new one are estimated for data calculated with ACAT code for D + ions incident obliquely on C, Fe and W materials in incident-energy regions from several tens of eV to 10 keV. Then, the parameters are expressed with functions of incident energy. The formula with the functions derived well reproduces that using the ACAT data in the whole energy range. (author)

  18. DuoPIGatron ion sources for PLT injectors

    International Nuclear Information System (INIS)

    Tsai, C.C.; Stirling, W.L.; Haselton, H.H.; Davis, R.C.; Schechter, D.E.

    1977-01-01

    Plasma heating requirements for the Princeton Large Torus (PLT) are set at about 1 MJ total beam energy for 3 MW beam power of energetic hydrogen (or deuterium) neutrals at 40 keV. To fulfill this design goal from four neutral beam injectors, the duoPlGatron ion source originally developed at ORNL has been modified, developed, and scaled-up to versions with 20-cm and/or 22-cm grid diameters. Utilizing the multipole line cusp magnetic field confinement for the ionizing electrons and created Philips Ionization Gauge (PIG) plasma, these sources generate a uniform (+-5 percent density variation over 23-cm diam) and dense plasma (about 2 x 10 12 cm 3 at the extraction surface). Such sources have been operated reliably to deliver a beam current exceeding 70 A of hydrogen ions at 40 keV. For such a beam condition the source is capable of running with an arc pulse of 0.5 sec. Moreover, the corresponding arc efficiency is very high, below 1.0 KW arc power per ampere of ion beam current. In this paper we describe the plasma generation, source characteristics and arc efficiency as functions of magnetic fields, gas pressure, and arc power (including the arc voltage and current). The other exciting feature, high proton yield (exceeding 80 percent), will be discussed

  19. Methane Yield Database: Online infrastructure and bioresource for methane yield data and related metadata.

    Science.gov (United States)

    Murovec, Boštjan; Kolbl, Sabina; Stres, Blaž

    2015-01-01

    The aim of this study was to develop and validate a community supported online infrastructure and bioresource for methane yield data and accompanying metadata collected from published literature. In total, 1164 entries described by 15,749 data points were assembled. Analysis of data collection showed little congruence in reporting of methodological approaches. The largest identifiable source of variation in reported methane yields was represented by authorship (i.e. substrate batches within particular substrate class) within which experimental scales (volumes (0.02-5l), incubation temperature (34-40 °C) and % VS of substrate played an important role (p 63%). This calls for reconsideration of accepted approaches to reporting data in currently published literature to increase capacity to service industrial decision making to a greater extent. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Climate Change Impact on Rainfall: How will Threaten Wheat Yield?

    Science.gov (United States)

    Tafoughalti, K.; El Faleh, E. M.; Moujahid, Y.; Ouargaga, F.

    2018-05-01

    Climate change has a significant impact on the environmental condition of the agricultural region. Meknes has an agrarian economy and wheat production is of paramount importance. As most arable area are under rainfed system, Meknes is one of the sensitive regions to rainfall variability and consequently to climate change. Therefore, the use of changes in rainfall is vital for detecting the influence of climate system on agricultural productivity. This article identifies rainfall temporal variability and its impact on wheat yields. We used monthly rainfall records for three decades and wheat yields records of fifteen years. Rainfall variability is assessed utilizing the precipitation concentration index and the variation coefficient. The association between wheat yields and cumulative rainfall amounts of different scales was calculated based on a regression model. The analysis shown moderate seasonal and irregular annual rainfall distribution. Yields fluctuated from 210 to 4500 Kg/ha with 52% of coefficient of variation. The correlation results shows that wheat yields are strongly correlated with rainfall of the period January to March. This investigation concluded that climate change is altering wheat yield and it is crucial to adept the necessary adaptation to challenge the risk.

  1. Wheat yield vulnerability: relation to rainfall and suggestions for adaptation

    Directory of Open Access Journals (Sweden)

    Khalid Tafoughalti

    2018-04-01

    Full Text Available Wheat production is of paramount importance in the region of Meknes, which is mainly produced under rainfed conditions. It is the dominant cereal, the greater proportion being the soft type. During the past few decades, rainfall flaws have caused a number of cases of droughts. These flaws have seriously affecting wheat production. The main objective of this study is the assessment of rainfall variability at monthly, seasonal and annual scales and to determine their impact on wheat yields. To reduce this impact we suggested some mechanisms of adaptation. We used monthly rainfall records for three decades and wheat yields records of fifteen years. Rainfall variability is assessed utilizing the precipitation concentration index and the variation coefficient. The association between wheat yields and cumulative rainfall amounts of different scales was calculated based on a regression model to evaluate the impact of rainfall on wheat yields. Data analysis shown moderate seasonal and irregular annual rainfall distribution. Yields fluctuated from 210 to 4500 Kg/ha with 52% of coefficient of variation. The correlation results shows that soft wheat and hard wheat are strongly correlated with the period of January to March than with the whole growing-season. While they are adversely correlated with the mid-spring. This investigation concluded that synchronizing appropriate adaptation with the period of January to March was crucial to achieving success yield of wheat.

  2. Sequential Path Model for Grain Yield in Soybean

    Directory of Open Access Journals (Sweden)

    Mohammad SEDGHI

    2010-09-01

    Full Text Available This study was performed to determine some physiological traits that affect soybean,s grain yield via sequential path analysis. In a factorial experiment, two cultivars (Harcor and Williams were sown under four levels of nitrogen and two levels of weed management at the research station of Tabriz University, Iran, during 2004 and 2005. Grain yield, some yield components and physiological traits were measured. Correlation coefficient analysis showed that grain yield had significant positive and negative association with measured traits. A sequential path analysis was done in order to evaluate associations among grain yield and related traits by ordering the various variables in first, second and third order paths on the basis of their maximum direct effects and minimal collinearity. Two first-order variables, namely number of pods per plant and pre-flowering net photosynthesis revealed highest direct effect on total grain yield and explained 49, 44 and 47 % of the variation in grain yield based on 2004, 2005, and combined datasets, respectively. Four traits i.e. post-flowering net photosynthesis, plant height, leaf area index and intercepted radiation at the bottom layer of canopy were found to fit as second-order variables. Pre- and post-flowering chlorophyll content, main root length and intercepted radiation at the middle layer of canopy were placed at the third-order path. From the results concluded that, number of pods per plant and pre-flowering net photosynthesis are the best selection criteria in soybean for grain yield.

  3. Effective charge of energetic ions in metals

    International Nuclear Information System (INIS)

    Kitagawa, M.; Brandt, W.

    1983-01-01

    The effective charge of energetic ion, as derived from stopping power of metals, is calculated by use of a dielectronic-response function method. The electronic distribution in the ion is described through the variational principle in a statistical approximation. The dependences of effective charge on the ion velocity, atomic number and r/sub s/-value of metal are derived at the low-velocity region. The effective charge becomes larger than the real charge of ion due to the close collisions. We obtain the quasi-universal equation of the fractional effective electron number of ion as a function of the ratio between the ionic size and the minimum distance approach. The comparsion between theoretical and experimental results of the effective charge is performed for the cases of N ion into Au, C and Al. We also discuss the equipartition rule of partially ionized ion at the high-velocity region

  4. SURVEY OF THE SPECTRA OF THE DIVALENT RARE EARTH IONS IN CUBIC CRYSTALS

    Energy Technology Data Exchange (ETDEWEB)

    McClure, Donald S. [Univ. of Chicago, IL (United States); Kiss, Zoltan J. [RCA Laboratories, Princeton, NJ (United States)

    1963-04-15

    The rare earth ions may exist in the divalent state in suitable host crystals such as CaF/sub 2/. All of the trivalent ions from La to Yb are reduced in situ to the divalent state in CaF/sub 2/ by gamma irradiation. The spectra of most of these ions show that the ground and first few excited states derive from f/sup n/ configurations, but the wesk absorption due to these is masked at higher energies by strong broad bands of the parity permitted f/sup n/ yields f/sup n-1/ d transitions. The excitation energy of these spectra have been calculated in a first approximation as the energy difference between the Hund Rule'' single determinant states of the configurations f/sup n -1/d and f/sup n/. This procedure satisfactorily accounts for the remarkable variations in the excitation energy in passing from one ion to the next in the series with the exception of Ge/ sup 2+/ Ce/sup 2+/, and Tb/sup 2+/, Ge/sup 2+/ probably has f/sup 7/d for its ground con figuration, while Ce/sup 2+/ and Tb/sup 2+/ are borderline cases. The spectral structure probably arises chiefly from the crystal field splitting of the d-orbital, since each ion in CaF/sub 2/ has a similar spectrum, and the spectra change drastically in sites of other than cubic symmetry. (auth)

  5. Nuclear yield determinations using isotope-separator-on-line arrangements

    International Nuclear Information System (INIS)

    Rudstam, G.

    1975-01-01

    The delay between the formation of a nuclear reaction product and its collection in front of measuring equipment in ISOL arrangements using integrated target-ion source systems has been analyzed. It is shown that a typical delay function takes the form const x (1-esup(-γt))esup(-μt) with γ >> μ. The results can be used for decay corrections in nuclear yield determinations. (Auth.)

  6. Yield strength of attached copper film

    International Nuclear Information System (INIS)

    Zhang Yan; Zhang Jian-Min

    2011-01-01

    Variation of stress in attached copper film with an applied strain is measured by X-ray diffraction combined with a four-point bending method. A lower slope of the initial elastic segment of the curve of X-ray measured stress versus applied strain results from incomplete elastic strain transferred from the substrate to the film due to insufficiently strong interface cohesion. So the slope of the initial elastic segment of the X-ray stress (or X-ray strain directly) of the film against the substrate applied strain may be used to measure the film-substrate cohesive strength. The yield strength of the attached copper film is much higher than that of the bulk material and varies linearly with the inverse of the film thickness. (condensed matter: structural, mechanical, and thermal properties)

  7. Evaluation of Yield and Yield Attributes of Five Sweet Potato ...

    African Journals Online (AJOL)

    0087, and TIS 2532.OP.1.13) were evaluated for yield and agronomic performance in Imo State University Farm, Owerri. The experiment was laid out in a randomised complete block design with three replications. The planting density was 33,000 ...

  8. Heterosis and combining ability for grain yield and yield component ...

    African Journals Online (AJOL)

    ... ranged from 0 to -13% indicating that the hybrids tend to be earlier in maturity than the parents. The mean squares due to GCA for days to maturity, ear diameter, member of kernels per row, 1000 kernel weight and grain yield were significant, indicating the importance of additive genetic variance in controlling these traits.

  9. Rice yield prediction from yield components and limiting factors

    NARCIS (Netherlands)

    Casanova, D.; Goudriaan, J.; Catala Former, M.M.; Withagen, J.C.M.

    2002-01-01

    This article aims to quantify growth at field level in relation to crop status and soil properties in irrigated direct-seeded rice. Forty fields were selected in the Ebro Delta (Spain). Rice growth was monitored and soil properties measured. Yield was related to soil properties by a deductive

  10. Correlation Analysis of some Growth, Yield, Yield Components and ...

    African Journals Online (AJOL)

    three critical growth stages which was imposed by withholding water (at ... November, 5th December, 19th December and 2nd January) laid out in a split ... Simple correlation coefficient ® of different crop parameters and grain yield ... The husk bran and germ are rich sources of ..... heat in 2009/2010 dry season at Fadam a ...

  11. Status of fission yield data

    International Nuclear Information System (INIS)

    England, T.R.; Blachot, J.

    1988-01-01

    In this paper we summarize the current status of the recent US evaluation for 34 fissioning nuclides at one or more neutron incident energies and for spontaneous fission. Currently there are 50 yields sets, and for each we have independent and cumulative yields and uncertainties for approximately 1100 fission products. When finalized the recommended data will become part of Version VI of the US ENDF/B. Other major evaluations in progress that are included in a recently formed IAEA Coordinated Research Program are also summarized. In a second part we review two empirical models in use to estimate independent yields. Comparison of model estimates with measured data is presented, including a comparison with some recent data obtained from Lohengrin (Cf-249 T). 18 refs., 13 figs., 3 tabs

  12. Swift heavy ion irradiation effects in {alpha} poly(vinylidene fluoride); Etude des effets induits par les ions lourds energetiques dans le poly(fluorure de vinylidene)

    Energy Technology Data Exchange (ETDEWEB)

    Le Bouedec, A

    1999-11-29

    The goal of this study is to characteristic and to localised defects created in {alpha} Poly (vinylidene fluoride) after swift heavy ion irradiations. PVDF films are irradiated with several Swift Heavy Ions (SHI), in the electronic stopping power (dE/dx){sub e}, in order to study the influence of irradiation parameters (absorbed dose, ion). These irradiated films are studied by different analysis techniques such as FTIR, ESR (X and Q band) spectroscopies and DSC. The crystalline level of PVDF is about 50% and we follow it destruction and amorphization as the absorbed dose increase by DSC and FTIR studies. The variation of the various FTIR bands allow us to observe the unsaturations induced by SHI radiations. Two sets of defects are observed: those which yield is sensitive to an increase of (dE/dx){sub e} and those that are not. A spatial distribution of the various defects within the talent track is provided and defects that are difficult to create are the closest of the ion path. The different kind of radicals created after irradiations are studied by ESR spectroscopy. Alkyl, peroxy and polyenyl radicals are detected after SHI radiations like after electron or {gamma} irradiations. Their yield of creation is independent of (dE/dx){sub e} and their localised in the crystalline zone or/and at the interfacial zone between crystalline and amorphous one. An other kind of radicals is created only after SHI radiations that are specific of the SHI-polymer interaction. We observe that these radicals are localised on a carbon cluster, in the core of the latent track for low doses and highly sensitive at the (dE/dx){sub e} of the ion. (author)

  13. Maximization of DRAM yield by control of surface charge and particle addition during high dose implantation

    Science.gov (United States)

    Horvath, J.; Moffatt, S.

    1991-04-01

    Ion implantation processing exposes semiconductor devices to an energetic ion beam in order to deposit dopant ions in shallow layers. In addition to this primary process, foreign materials are deposited as particles and surface films. The deposition of particles is a major cause of IC yield loss and becomes even more significant as device dimensions are decreased. Control of particle addition in a high-volume production environment requires procedures to limit beamline and endstation sources, control of particle transport, cleaning procedures and a well grounded preventative maintenance philosophy. Control of surface charge by optimization of the ion beam and electron shower conditions and measurement with a real-time charge sensor has been effective in improving the yield of NMOS and CMOS DRAMs. Control of surface voltages to a range between 0 and -20 V was correlated with good implant yield with PI9200 implanters for p + and n + source-drain implants.

  14. Existence of evolutionary variational solutions via the calculus of variations

    Science.gov (United States)

    Bögelein, Verena; Duzaar, Frank; Marcellini, Paolo

    In this paper we introduce a purely variational approach to time dependent problems, yielding the existence of global parabolic minimizers, that is ∫0T ∫Ω [uṡ∂tφ+f(x,Du)] dx dt⩽∫0T ∫Ω f(x,Du+Dφ) dx dt, whenever T>0 and φ∈C0∞(Ω×(0,T),RN). For the integrand f:Ω×R→[0,∞] we merely assume convexity with respect to the gradient variable and coercivity. These evolutionary variational solutions are obtained as limits of maps depending on space and time minimizing certain convex variational functionals. In the simplest situation, with some growth conditions on f, the method provides the existence of global weak solutions to Cauchy-Dirichlet problems of parabolic systems of the type ∂tu-divDξf(x,Du)=0 in Ω×(0,∞).

  15. Ion channeling revisited

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, Barney Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Corona, Aldo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nguyen, Anh [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    A MS Excel program has been written that calculates accidental, or unintentional, ion channeling in cubic bcc, fcc and diamond lattice crystals or polycrystalline materials. This becomes an important issue when simulating the creation by energetic neutrons of point displacement damage and extended defects using beams of ions. All of the tables and graphs in the three Ion Beam Analysis Handbooks that previously had to be manually looked up and read from were programed into Excel in handy lookup tables, or parameterized, for the case of the graphs, using rather simple exponential functions with different powers of the argument. The program then offers an extremely convenient way to calculate axial and planar half-angles and minimum yield or dechanneling probabilities, effects on half-angles of amorphous overlayers, accidental channeling probabilities for randomly oriented crystals or crystallites, and finally a way to automatically generate stereographic projections of axial and planar channeling half-angles. The program can generate these projections and calculate these probabilities for axes and [hkl] planes up to (555).

  16. Heavy Ion Fusion Accelerator Research (HIFAR)

    International Nuclear Information System (INIS)

    1991-04-01

    This report discusses the following topics: emittance variations in current-amplifying ion induction lina; transverse emittance studies of an induction accelerator of heavy ions; drift compression experiments on MBE-4 and related emittance; low emittance uniform- density C s + sources for heavy ion fusion accelerator studies; survey of alignment of MBE-4; time-of-flight dependence on the MBE-4 quadrupole voltage; high order calculation of the multiple content of three dimensional electrostatic geometries; an induction linac injector for scaled experiments; induction accelerator test module for HIF; longitudinal instability in HIF beams; and analysis of resonant longitudinal instability in a heavy ion induction linac

  17. Li-ion batteries: Phase transition

    International Nuclear Information System (INIS)

    Hou Peiyu; Zhang Yantao; Zhang Lianqi; Chu Geng; Gao Jian

    2016-01-01

    Progress in the research on phase transitions during Li + extraction/insertion processes in typical battery materials is summarized as examples to illustrate the significance of understanding phase transition phenomena in Li-ion batteries. Physical phenomena such as phase transitions (and resultant phase diagrams) are often observed in Li-ion battery research and already play an important role in promoting Li-ion battery technology. For example, the phase transitions during Li + insertion/extraction are highly relevant to the thermodynamics and kinetics of Li-ion batteries, and even physical characteristics such as specific energy, power density, volume variation, and safety-related properties. (topical review)

  18. Ion channeling

    International Nuclear Information System (INIS)

    Erramli, H.; Blondiaux, G.

    1994-01-01

    Channeling phenomenon was predicted, many years ago, by stark. The first channeling experiments were performed in 1963 by Davies and his coworkers. Parallely Robinson and Oen have investigated this process by simulating trajectories of ions in monocrystals. This technique has been combined with many methods like Rutherford Backscattering Spectrometry (R.B.S.), Particles Induced X-rays Emission (P.I.X.E) and online Nuclear Reaction (N.R.A.) to localize trace elements in the crystal or to determine crystalline quality. To use channeling for material characterization we need data about the stopping power of the incident particle in the channeled direction. The ratios of channeled to random stopping powers of silicon for irradiation in the direction have been investigated and compared to the available theoretical results. We describe few applications of ion channeling in the field of materials characterization. Special attention is given to ion channeling combined with Charged Particle Activation Analysis (C.P.A.A.) for studying the behaviour of oxygen atoms in Czochralski silicon lattices under the influence of internal gettering and in different gaseous atmospheres. Association between ion channeling and C.P.A.A was also utilised for studying the influence of the growing conditions on concentration and position of carbon atoms at trace levels in the MOVPE Ga sub (1-x) Al sub x lattice. 6 figs., 1 tab., 32 refs. (author)

  19. Ion source

    International Nuclear Information System (INIS)

    1977-01-01

    The specifications of a set of point-shape electrodes of non-corrodable material that can hold a film of liquid material of equal thickness is described. Contained in a jacket, this set forms an ion source. The electrode is made of tungsten with a glassy carbon layer for insulation and an outer layer of aluminium-oxide ceramic material

  20. Conservation of fusion reaction optimum yield in focused discharges with variable voltage and energy but constant geometry

    International Nuclear Information System (INIS)

    Bilbao, L.; Bortolotti, A.; Brzosko, J.; DeChiara, P.; Kilic, H.; Mezzetti, F.; Nardi, V.; Powell, C.; Wang, J.

    1992-01-01

    The D-D fusion reaction yield per pulse, Y n , of focused discharges is monitored by changing the capacitor bank voltage Vo by a factor 2 without any change of construction parameters and of the filling gas pressure of two plasma focus machines PF1 (C1 congruent 50 microfarad, L1 congruent 20 nanohenry) and PF2 (C2 = 1.2Cl, L2 = 2L1). The interval Δ = 1 ± (ΔW)/W of the capacitor bank energy values W on which the scaling Y n ∼ W 2 applies is greater for PF2, where the corresponding variation ΔI2 of the peak electrode current I2 is smaller (in agreement with Lw/C2 > L1/C1) than for PF1. Suitable figure of merit (in terms of ΔI, ΔW, L, C, etc.) are used for determining the relative importance of (i), the induced variations of the pinch fine structure and of (ii), the variations of the insulator surface at the PF breech, with bearing on the initial stage of the current sheath formation. Schlieren and magnetic probe data monitor the current sheath structure and propagation speed. The D + ion emission from the pinch is monitored in the energy interval 50 keV to 25 MeV for clarifying the links between the pinch fine structure and the set of leading macroscopic parameters of the PF discharges

  1. Surface ripple evolution by argon ion irradiation in polymers

    International Nuclear Information System (INIS)

    Goyal, Meetika; Aggarwal, Sanjeev; Sharma, Annu

    2016-01-01

    In this report, an attempt has been made to investigate the morphological evolution of nanoscale surface ripples on aliphatic (polypropylene, PP) and aromatic (polyethylene terephthalate, PET) polymeric substrates irradiated with 50 keV Ar"+ ions. The specimens were sputtered at off normal incidence of 30° with 5 × 10"1"6 Ar"+ cm"−"2. The topographical features and structural behavior of the specimens were studied using Atomic Force Microscopy (AFM) and UV-Visible spectroscopy techniques, respectively. The Stopping and Range of Ions in Matter simulations were performed to calculate sputtering yield of irradiated PP and PET polymers. Sputtering yield of carbon atoms has been found to be smaller for PP (0.40) as compared to PET (0.73), which is attributed to the different structures of two polymers. AFM analysis demonstrates the evolution of ripple like features with amplitude (2.50 nm) and wavelength (690 nm) on PET while that of lower amplitude (1.50 nm) and higher wavelength (980 nm) on PP specimen. The disorder parameter (Urbach energy) has been found to increase significantly from 0.30 eV to 1.67 eV in case of PP as compared to a lesser increase from 0.35 eV to 0.72 eV in case of PET as revealed by UV-Visible characterization. A mutual correlation between ion beam sputtering induced topographical variations with that of enhancement in the disorder parameter of the specimens has been discussed.

  2. Variations in recruitment yield, costs, speed and participant diversity across Internet platforms in a global study examining the efficacy of an HIV/AIDS and HIV testing animated and live-action video among English- or Spanish-speaking Internet or social media users

    Directory of Open Access Journals (Sweden)

    Winnie Shao

    2015-04-01

    Full Text Available For a world-wide, Internet-based study on HIV/AIDS and HIV testing knowledge, we compared the yields, speed and costs of recruitment and participant diversity across free postings on 13 Internet or social media platforms, paid advertising or postings on 3 platforms, and separate free postings and paid advertisements on Facebook. Platforms were compared by study completions (yield, time to completion, completion to enrollment ratios (CERs, and costs/completion; and by participants’ demographic characteristics, HIV testing history, and health literacy levels. Of the 482 English-speaking participants, Amazon Mechanical Turk yielded the most participants, recruited participants at the fastest rate and had the highest CER (0.78 and lowest costs/completion. Of the 335 Spanish-speaking participants, Facebook yielded the most participants and recruited participants at the fastest rate, although Amazon Mechanical Turk had the highest CER (0.72 and lowest costs/completion. Across platforms participants differed substantially according to their demographic characteristics, HIV testing history and health literacy skills. The study results highlight the need for researchers to strongly consider choice of Internet or social media platforms when conducting Internet-based research. Because of the sample specifications and cost restraints of studies, specific Internet/social media or participant selection platforms will be much more effective or appropriate than others.

  3. VARIATIONS IN RECRUITMENT YIELD, COSTS, SPEED AND PARTICIPANT DIVERSITY ACROSS INTERNET PLATFORMS IN A GLOBAL STUDY EXAMINING THE EFFICACY OF AN HIV/AIDS AND HIV TESTING ANIMATED AND LIVE-ACTION VIDEO AMONG ENGLISH- OR SPANISH-SPEAKING INTERNET OR SOCIAL MEDIA USERS.

    Science.gov (United States)

    Shao, Winnie; Guan, Wentao; Clark, Melissa A; Liu, Tao; Santelices, Claudia; Cortés, Dharma E; Merchant, Roland C

    For a world-wide, Internet-based study on HIV/AIDS and HIV testing knowledge, we compared the yields, speed and costs of recruitment and participant diversity across free postings on 13 Internet or social media platforms, paid advertising or postings on 3 platforms, and separate free postings and paid advertisements on Facebook. Platforms were compared by study completions (yield), time to completion, completion to enrollment ratios (CERs), and costs/ completion; and by participants' demographic characteristics, HIV testing history, and health literacy levels. Of the 482 English-speaking participants, Amazon Mechanical Turk yielded the most participants, recruited participants at the fastest rate and had the highest CER (0.78) and lowest costs / completion. Of the 335 Spanish-speaking participants, Facebook yielded the most participants and recruited participants at the fastest rate, although Amazon Mechanical Turk had the highest CER (0.72) and lowest costs/completion. Across platforms participants differed substantially according to their demographic characteristics, HIV testing history and health literay skills. The study results highlight the need for researchers to strongly consider choice of Internet or social media plaforms when conducting Internet-based research. Because of the sample specifications and cost restraints of studies, specific Internet/ social media or participant selection plaforms will be much more effective or appropriate than others.

  4. Assessing potential sustainable wood yield

    Science.gov (United States)

    Robert F. Powers

    2001-01-01

    Society is making unprecedented demands on world forests to produce and sustain many values. Chief among them is wood supply, and concerns are rising globally about the ability of forests to meet increasing needs. Assessing this is not easy. It requires a basic understanding of the principles governing forest productivity: how wood yield varies with tree and stand...

  5. NIF total neutron yield diagnostic

    International Nuclear Information System (INIS)

    Cooper, Gary W.; Ruiz, Carlos L.

    2001-01-01

    We have designed a total neutron yield diagnostic for the National Ignition Facility (NIF) which is based on the activation of In and Cu samples. The particular approach that we have chosen is one in which we calibrate the entire counting system and which we call the ''F factor'' method. In this method, In and/or Cu samples are exposed to known sources of DD and DT neutrons. The activated samples are then counted with an appropriate system: a high purity Ge detector for In and a NaI coincidence system for Cu. We can then calculate a calibration factor, which relates measured activity to total neutron yield. The advantage of this approach is that specific knowledge of such quantities as cross sections and detector efficiencies is not needed. Unless the actual scattering environment of the NIF can be mocked up in the calibration experiment, the F factor will have to be modified using the results of a numerical simulation of the NIF scattering environment. In this article, the calibration factor methodology will be discussed and experimental results for the calibration factors will be presented. Total NIF neutron yields of 10 9 --10 19 can be measured with this method assuming a 50 cm stand-off distance can be employed for the lower yields

  6. Soybean yield in relation to distance from the Itaipu reservoir

    Science.gov (United States)

    de Faria, Rogério Teixeira; Junior, Ruy Casão; Werner, Simone Silmara; Junior, Luiz Antônio Zanão; Hoogenboom, Gerrit

    2016-07-01

    Crops close to small water bodies may exhibit changes in yield if the water mass causes significant changes in the microclimate of areas near the reservoir shoreline. The scientific literature describes this effect as occurring gradually, with higher intensity in the sites near the shoreline and decreasing intensity with distance from the reservoir. Experiments with two soybean cultivars were conducted during four crop seasons to evaluate soybean yield in relation to distance from the Itaipu reservoir and determine the effect of air temperature and water availability on soybean crop yield. Fifteen experimental sites were distributed in three transects perpendicular to the Itaipu reservoir, covering an area at approximately 10 km from the shoreline. The yield gradient between the site closest to the reservoir and the sites farther away in each transect did not show a consistent trend, but varied as a function of distance, crop season, and cultivar. This finding indicates that the Itaipu reservoir does not affect the yield of soybean plants grown within approximately 10 km from the shoreline. In addition, the variation in yield among the experimental sites was not attributed to thermal conditions because the temperature was similar within transects. However, the crop water availability was responsible for higher differences in yield among the neighboring experimental sites related to water stress caused by spatial variability in rainfall, especially during the soybean reproductive period in January and February.

  7. Photophysics of the variable quantum yield of asymmetric bilirubin

    International Nuclear Information System (INIS)

    Troup, G.J.

    1998-01-01

    Full text: Bilirubin (BR), responsible for neonatal jaundice, is a molecule containing two pyrromethenone chromophores conjoined by a 'saturated' carbon CH 2 group. Because this disease is cured by phototherapy, BR has been extensively studied by laser means. When the chromophores in each half of the molecule are identical, we have symmetrical BR (SBR); when they are not, we have asymmetric BR (ASBR). The quantum yield of the photoproducts in simple organic solution from SBR is not wavelength-dependent, while that from ASBR is. Because of the proximity of the two chromophores, both the SBR and ASBR systems are subject to Davidoff (dynamic electric dipole) splitting of the chromophore excited states. A quantum mechanical calculation shows that when the two (ASBR) chromophore states are not degenerate, the higher Davidoff state is preferentially occupied by the chromophore with the 'original' higher energy, and the lower Davidoff state by the chromophore of 'original' lower energy. This is just what is required for the quantum yield to vary with wavelength. If the variation of the quantum yield of ASBR in the presence of human serum albumen is approximated by a square-wave (narrow line approximation), the deduced ratio of the short wavelength photoproduct yield with the long wavelength one is in agreement with accepted values for the 'original' energy difference of the chromophores, and the Davidoff splitting parameter. A previous explanation has involved variation of relaxation processes with wavelength, but only qualitatively. The quantum yields for SBRs bonded to HSA are not yet published, but show wavelength variation, possibly from asymmetric bonding. In 0.1% ammonia/methanol however, there is no such variation for the SBRs, while for ASBR, there is, and the photoproduct ratios for long and short wavelength are reciprocals of one another, as predicted by our theory

  8. GENETIC ANALYSIS OF YIELD AND YIELD COMPONENTS IN ...

    African Journals Online (AJOL)

    ACSS

    2017-11-16

    Nov 16, 2017 ... used different genotypes and the environmental conditions under which their ... and Jinks (1971):. Y = m + aa + βd + a2aa + 2aβad +β2dd … .... /plant, 100-grain weight per plant and Grain yield per plant (g) of six generations in IET6279 X IR70445-146-3-. 3 cross. Traits. Generation. Mean. Standard. Range.

  9. Potato yield and yield structure depending on irrigation

    Directory of Open Access Journals (Sweden)

    Milić Stanko

    2010-01-01

    Full Text Available In the agroclimatic conditions of the Vojvodina Province, the application of an economic water regime and modern technology is necessary for stable and intensive potato production. A two-year experiment on calcareous chernozem was carried out to determine how irrigation and different pre-irrigation soil moisture affect potato yield and distribution of tuber fraction in the potato yield. The block-design trial had four replicates and was adapted for sprinkler irrigation conditions. It included four treatments: irrigation with pre-irrigation moisture levels of 60 % of field water capacity (FC, irrigation with pre-irrigation moisture levels of 70 % (FC, irrigation with pre-irrigation moisture levels of 80% (FC, and a non-irrigated control treatment. Irrigation significantly increased the yield of potato, which increased from 37.27 % to 75.86 %. Under irrigation, the percentage of small fractions decreased in favour of the 55 mm one, or fractions above the 45-55 mm range. On average, irrigated treatments produced significantly more tubers than the conditions of natural water supply. .

  10. Ion temperature gradient instability

    International Nuclear Information System (INIS)

    1989-01-01

    Anomalous ion thermal conductivity remains an open physics issue for the present generation of high temperature Tokamaks. It is generally believed to be due to Ion Temperature Gradient Instability (η i mode). However, it has been difficult, if not impossible to identify this instability and study the anomalous transport due to it, directly. Therefore the production and identification of the mode is pursued in the simpler and experimentally convenient configuration of the Columbia Linear Machine (CLM). CLM is a steady state machine which already has all the appropriate parameters, except η i . This parameter is being increased to the appropriate value of the order of 1 by 'feathering' a tungsten screen located between the plasma source and the experimental cell to flatten the density profile and appropriate redesign of heating antennas to steepen the ion temperature profile. Once the instability is produced and identified, a thorough study of the characteristics of the mode can be done via a wide range of variation of all the critical parameters: η i , parallel wavelength, etc

  11. Electronic excitation effects on secondary ion emission in highly charged ion-solid interaction

    International Nuclear Information System (INIS)

    Sekioka, T.; Terasawa, M.; Mitamura, T.; Stoeckli, M.P.; Lehnert, U.; Fehrenbach, C.

    2001-01-01

    In order to investigate the secondary ion emission from the surface of conductive materials bombarded by highly charged heavy ions, we have done two types of experiments. First, we have measured the yield of the sputtered ions from the surface of solid targets of conductive materials (Al, Si, Ni, Cu) bombarded by Xe q+ (q=15-44) at 300 keV (v p =0.30 a.u) and at 1.0 MeV (v p =0.54 a.u). In view of the secondary ion yields as a function of the potential energy of the projectile, the increase rates below q=35, where the potential energy amounts to 25.5 keV, were rather moderate and showed a prominent increase above q=35. These phenomena were rather strong in the case of the metal targets. Second, we have measured the energy dependence of the yield of the sputtered ions from the surface of solid targets of conductive materials (C, Al) bombarded by Xe q+ (q=30,36,44) between 76 keV (v p =0.15 a.u) and 6.0 MeV (v p =1.3 a.u). A broad enhancement of the secondary ion yield has been found for Al target bombarded by Xe 44+ . From these experimental results, the electronic excitation effects in conductive materials for impact of slow highly charged heavy ions bearing high potential energy is discussed

  12. Design of the compact ECR ion source for heavy-ion therapy

    International Nuclear Information System (INIS)

    Muramatsu, M.; Kitagawa, A.; Sato, S.; Sato, Y.; Yamada, S.; Hattori, T.; Shibuya, S.

    1999-01-01

    Heavy ion cancer treatment is successfully being done at the Heavy Ion Medical Accelerator in Chiba (HIMAC). Design philosophy for the ion sources for medical facilities are as follows: sufficient beam intensity, a few hundred eμA; long lifetime with good stability; easy operation and easy maintenance; and compactness. In order to develop such source for future heavy-ion facilities, we have tested compact electron cyclotron resonance (ECR) ion sources using permanent magnets both for axial and radial confinement of hot electrons. Since the yield of C 2+ ion in the firstly-developed source (2.45 GHz ECR) was 15 eμA and far below the medical requirement (-150 eμA for the HIMAC), a new source has been proposed, having the frequency of 10 GHz. The extracted intensity of C 4+ (and C 2+ ) ions is expected to be higher than 200 eμA. (author)

  13. Analysis of Yield and Yield Related Traits Variability of Winter Wheat (Triticum aestivum L. Cv. Izolda and Double Haploid Lines

    Directory of Open Access Journals (Sweden)

    Kozdój Janusz

    2015-12-01

    Full Text Available The yield-forming potential of winter wheat is determined by several factors, namely total number of shoots per plant and total number of spikelets per spike. The field experiments were conducted during three vegetation seasons at the Plant Breeding and Acclimatization Institute – National Research Institute (PBAI–NRI, located in Radzików, Poland. The objective of this study was a comparative analysis of the structural yield-forming factor levels, which determine grain yield per spike and per plant of the DH lines and standard Izolda cultivar. Results indicate that several DH lines showed some differences in tested morphological structures of plant, yield factor levels and in grain yield per spike and per plant in comparison to standard Izolda, regardless of the year. Mean grain yield per plant of DH lines was 26.5% lower in comparison to standard Izolda only in the second year of study. It was caused by a reduction of productive tillers number. Structural yield-forming potential of DH lines was used in 38% and 59% and in case of Izolda in 47% and 61% (the second and the third year of experiment, respectively. The mean grain yield per spike of DH lines was 14.8% lower than Izolda cultivar only in third year of experiment and it was caused by about 12% lower number of grains per spike. Structural yield-forming potential of DH spikes was used in 82.4%, 85.4% and 84.9% and in case of Izolda in 83.8%, 87% and 89.5% (the first, the second and the third year of experiment, respectively. The grain yield per winter wheat plant (both DH lines and standard Izolda was significantly correlated with the number of productive tillers per plant (r = 0.80. The grain yield per winter wheat spike (both DH lines and Izolda cultivar was significantly and highly correlated with the number of grains per spike (r = 0.96, number of fertile spikelets per spike (r = 0.87 and the spike length (r = 0.80. Variation of spike and plant structural yield-forming factors

  14. Ion-ion collisions and ion storage rings

    International Nuclear Information System (INIS)

    Mowat, J.R.

    1988-01-01

    Improved understanding of fundamental ion-ion interactions is expected to emerge from research carried out with ion storage rings. In this short survey the significant advantages and unique features that make stored ions useful targets for collision experiments are reviewed and discussed. It is pointed out that improvements to existing ion-ion experiments, as well as qualitatively new experiments, should occur over the next few years as ion storage rings become available for atomic physics. Some new experiments are suggested which are difficult if not impossible with present-day technology, but which seem feasible at storage rings facilities. (orig.)

  15. Effect of NS-nitragin application on soybean yield and yield components

    Directory of Open Access Journals (Sweden)

    Marinković Jelena

    2010-01-01

    Full Text Available Agricultural soils of Serbia are low in soybean symbiotic bacteria and application of bacteriological preparations has been introduced as a regular cultivation practice when growing soybean. A trial was set up on experimental field of Institute of Field and Vegetable Crops from Novi Sad on chernozem soil using a randomized block design with four replicates. Mineral nitrogen fertilizers were used in rates of 0, 30, 60, and 90 kg ha-1 in the experiment. Each of the nitrogen treatments had two variations, with and without inoculation. The effects of inoculation and different nitrogen fertilizer rates on yield and yield components were determined based on the pod number, seed number, 1000 seed mass and protein and oil content in seeds. Significantly higher pod number was observed in inoculated plants with the application of 30 kg N ha-1. Inoculation with NS-Nitragin increased seed number per plant. In treatment with no mineral nitrogen applied and with application of 30 kg N ha-1 and 60 kg N ha-1, 1000 seed mass was statistically higher in inoculated plants than in uninoculated ones. Inoculation produced statistically significant difference in soybean yield only in the treatment with no mineral nitrogen applied. Inoculation and applied mineral nitrogen rates had no significant effect on protein content in soybean grain.

  16. Chromosomal aberrations of the Chinese hamster cell line V79 after irradiation with X-rays and heavy ions

    International Nuclear Information System (INIS)

    Mueller, W.

    1985-02-01

    The study on hand examines chromosomal aberrations in Chinese hamster 79 cells. Irradiation involved a number of heavy ions ranging from neon to uranium with an energy variation between 0.3 and 20 MeV/u. Linear energy transfer ranged from 270 to 16,300 keV/μm. X-ray tests were run for reasons of comparison. Experiments showed the following results: 1) Aberration rate increases in dependence of nuclear charge number or LET resp. 2) The distribution of the chromosome-damage instances found differed markedly from corresponding measurements following irradiation with thinly ionizing radiation. In contrast to x-irradiation, it is possible, therefore, to obtain high aberration yields in preparations made immediately after irradiation. 3) The maximum of aberration yield after heavy-ion irradiation could be shown to occur as early as 4h after irradiation. This is true in x-irradiation for but small doses. 4) The radiation-sensitizing effect of caffeine and its action on the repair system of the cell could be confirmed for x-irradiation and could be described for heavy ions for the first time. 5) The radiation-protection effect of cysteamine could be re-affirmed for thinly ionizing radiation, however, it could not be verified for heavy ions. 6) Irradiation of cells by means of particles of a defined range supports the hypothesis that the particularly radiation-sensitive regions of the nucleus membrane constitute the cell's crucial target. (orig./MG) [de

  17. Photoionization and ion cyclotron resonance studies of the ion chemistry of ethylene oxide

    Science.gov (United States)

    Corderman, R. R.; Williamson, A. D.; Lebreton, P. R.; Buttrill, S. E., Jr.; Beauchamp, J. L.

    1976-01-01

    The formation of the ethylene oxide molecular ion and its subsequent ion-molecule reactions leading to the products C2H5O(+) and C3H5O(+) have been studied using time-resolved photoionization mass spectroscopy, ion cyclotron resonance spectroscopy, and photoelectron spectroscopy. An examination of the effects of internal energy on reactivity shows that the ratio of C3H5O(+) to C2H5O(+) increases by an order of magnitude with a single quantum of vibrational energy. The formation of (C2H4O/+/)-asterisk in a collision-induced isomerization is found which yields a ring-opened structure by C-C bond cleavage. The relaxed ring-opened C2H4O(+) ion reacts with neutral ethylene oxide by CH2(+) transfer to yield an intermediate product ion C3H6O(+) which gives C3H5O(+) by loss of H.

  18. Yield trends and yield gap analysis of major crops in the world

    OpenAIRE

    Hengsdijk, H.; Langeveld, J.W.A.

    2009-01-01

    This study aims to quantify the gap between current and potential yields of major crops in the world, and the production constraints that contribute to this yield gap. Using an expert-based evaluation of yield gaps and the literature, global and regional yields and yield trends of major crops are quantified, yield gaps evaluated by crop experts, current yield progress by breeding estimated, and different yield projections compared. Results show decreasing yield growth for wheat and rice, but ...

  19. Materials Science with Ion Beams

    CERN Document Server

    Bernas, Harry

    2010-01-01

    This book introduces materials scientists and designers, physicists and chemists to the properties of materials that can be modified by ion irradiation or implantation. These techniques can help design new materials or to test modified properties; novel applications already show that ion-beam techniques are complementary to others, yielding previously unattainable properties. Also, ion-beam interactions modify materials at the nanoscale, avoiding the often detrimental results of lithographic or chemical techniques. Here, the effects are related to better-known quasi-equilibrium thermodynamics, and the consequences to materials are discussed with concepts that are familiar to materials science. Examples addressed concern semiconductor physics, crystal and nanocluster growth, optics, magnetism, and applications to geology and biology.

  20. Mutagenic effects of ion implantation on stevia

    International Nuclear Information System (INIS)

    Wang Cailian; Shen Mei; Chen Qiufang; Lu Ting; Shu Shizhen

    1998-01-01

    Dry seeds of Stevia were implanted by 75 keV nitrogen and carbon ions with various doses. The biological effects in M 1 and mutation in M 2 were studied. The results showed that ion beam was able to induce variation on chromosome structure in root tip cells. The rate of cells with chromosome aberration was increased with ion beam dose. The rate of cells with chromosomal aberration was lower than that induced with γ-rays. Frequency of the mutation induced by implantation of N + and C + ions were higher than those induced by γ-rays. The rate of cell with chromosome aberration and in M 2 useful mutation induced by implantation of C + ion was higher than those induced by implantation of N + ion. Mutagenic effects Feng 1 x Riyuan and Riyuan x Feng 2 by implantation of N + and C + were higher than that of Jining and Feng 2