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The mobilities of the singly clustered ions of Li+ with constituent gases have been measured with a conventional drift tube over the E/N range 8–89 Td in N2, 10–25 Td in O2, 10–139 Td in CO, 50–348 Td in CO2, and 40–80 Td in CH4. Two methods were employed to determine the mobilities; one was a difference method and the other was based on the pressure dependence of apparent mobilities. It is found that the mobilities of each cluster ion species remain constant over most of the E/N range used and the zero-field values are 1.87±0.07 for Li+(N2)–N2 at 303 K, 1.89±0.11 for Li+(O2)–O2 at 303 K, 1.70±0.06 for Li+(CO)–CO at 303 K, 0.92±0.04 for Li+(CO2)–CO2 at 303 K, and 2.22±0.08 cm2/V s for Li+(CH4)–CH4 at 302 K, respectively. The zero-field mobilities of these polyatomic ions considerably deviate from the values of the Langevin polarization limit. They are predicted with moderate accuracy by assuming a hard sphere-r-4 potential which takes a repulsive core size into account. [ABSTRACT FROM AUTHOR]

The transport coefficients for Li+ ions in some moleculars gases have been measured over a wide range of E/N with a conventional drift tube at temperatures close to 300 K. The zero-field reduced mobilities are found to be 3.91±0.11, 4.44±0.12, 3.64±0.10, 2.46±0.07, and 3.44±0.10 cm2/V s in N2, O2, CO, CO2, and CH4 gas, respectively, and these values except in O2 gas significantly deviate from the Langevin limit. In N2, CO, and CO2 gas, the resulting mobility curves show clear minima at intermediate E/N, but the depressions in O2 and CH4 gas are slight. The drop of the zero-field values in N2, CO, and CO2 gas is explained in terms of an effective ion–quadrupole interaction which provides the r-6 attractive behavior. From the mobility calculations with using n-4–6(γ) potential, it is suggested that the depression of the mobility curve is developed by the addition of a sufficient r-6 term and is partly attributed to inelastic collisions as expected even at intermediate E/N. The experimental diffusion data are compared with the values derived from the generalized Einstein relation. For all systems, the agreement is quite good at intermediate E/N, but there are large discrepancies at other E/N. The sources of the deviation are considered to be clustering reactions and inelastic collisions at low and high field, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The generalized trajectory theory (the G-optk program) has been extended in order to make the method applicable to electron guns with curved and/or asymmetric cathodes. The object-image analysis mode has also been added. Enhanced capability of the upgraded G-optk program was demonstrated by applying the program to three electron optical systems: (a) the point cathode gun, (b) the hairpin-type cathode gun, and (c) the LEEM objective lens. The Canonical Mapping Transformation (CMT) diagrams were calculated both by direct ray tracing and by the upgraded G-optk program. In each case, it was found that the upgraded program reproduces well the results obtained by ray tracing. The generalized trajectory method has several advantages over direct ray tracing, such as substantially lighter calculation load and easy interpretation of the calculation results in terms of the optical parameters. [Copyright &y& Elsevier]

To investigate the relations between assimilations of photosynthetically fixed carbon (C) and newly absorbed nitrate, 13CO2 and 15NO3- were fed to five-week-old hydroponically grown spinach (Spinacia oleracea L. cv. Lead) plants, and the assimilation of 13C and 15N into biochemical fractions was followed at the whole plant level during six hours. After 75-min pulse feeding with 13CO2 and 90-min initial feeding with 15NO3- (designated as 0 h), the photosynthetically fixed 13C was largely found as the form of sugars in leaf blades and the newly absorbed 15N as nitrate in roots. During a further six hours of chase feeding with non-labeled CO2 and continuous 15NO3- supply, the amounts of 13C in sugars, organic acids, undefined C and amino acids gradually decreased in leaf blades while those in C compounds (except sugars and undefined C) increased in petioles and roots. 15N in the examined N compounds increased in all three organs. At 6 h, 13C in each organ was present as sugars (12–19%), undefined C (28–44%) or insoluble compounds (29–45%) and 15N as nitrate (15–24%) or undefined N (44–62%). During these six hours the assimilation of 15NO3- to reduced 15N seemed correlated with the utilization of 13C-labeled sugars in the three organs. [ABSTRACT FROM AUTHOR]

An easy method to prepare alkali ion emitters has been realized by using the ion-exchange technique. The thermionic emission characteristics of zeolite A alkali ion sources have been studied. Experimental results indicate that ion transport process within zeolite plays an important role in the emission mechanism. [ABSTRACT FROM AUTHOR]

In a drift-tube study, four simple formulas, based on a dynamic equilibrium analysis of two gaseous ion swarms, are proposed to determine simultaneously the forward and reverse reaction frequencies together with two drift velocities. The formulas are put to the test for (N+4,N+2)/N2 system with two arrival time spectra (ATS) generated from the experimental data previously reported at E/N=150 Td (the ratio of electric field strength to gas number density: 1 Td=10-17 V cm2). The percent differences between the data and the determined values are estimated to be 0.8%, -1.4%, 6.8%, and 4.9%, for the drift velocities of N+4 and N+2 ions and the forward and reverse reaction frequencies, respectively. For the same system, two experimental ATS obtained at 180 Td by McKnight et al., being supposedly in near equilibrium, are directly examined by this method. [ABSTRACT FROM AUTHOR]

In a drift-tube analysis, an asymptotic solution for the transport of inter-reacting multiple ion swarms approaching to dynamic equilibrium is proposed. The solution describes a set of similar Gaussian profiles with two common ‘‘equilibrium’’ transport coefficients. Although all the profiles apparently aggregate to the same location, there exists a slight peak difference between arbitrary two spectra. The difference holds even in the equilibrium. A generalized equilibrium constant is defined by the quotient of two reaction-frequency determinants. Those four kinetic constants are uniquely determined from the kinetic coefficients of all ion species without any influence of the initial conditions. The discrepancy between the thermal equilibrium and dynamic equilibrium is briefly discussed. [ABSTRACT FROM AUTHOR]

Background ImmuBalance™ is a koji fungus ( Aspergillus oryzae) and lactic acid fermented soybean product. This unique production process is believed to create a food supplement that helps to induce or maintain normal immune response. Objective To assess possible therapeutic effects of ImmuBalance™ on peanut (PN) hypersensitivity using a murine model of peanut allergy (PNA). Methods PN allergic C3H/HeJ mice were fed standard mouse chow containing 0.5% or 1.0% ImmuBalance (ImmuBalance 2X), radiation-inactivated 1.0% ImmuBalance (I-ImmuBalance 2X), or regular diet chow (sham) for 4 weeks, beginning 10 weeks after the initial PN sensitization, and then challenged with PN. Anaphylactic symptom scores, plasma histamine, serum PN specific-IgE levels and splenocyte cytokine profiles were determined. Results While 100% of sham-treated PNA mice developed anaphylactic reactions with a median score of 3.3 following PN challenge, only 50% of ImmuBalance, 30% of ImmuBalance 2X and 40% of I-ImmuBalance 2X-treated mice developed allergic reactions with median scores of 1.0, 0.4 and 0.5 respectively, which were significantly less than that in the sham-treated mice ( P<0.05). Plasma histamine and PN specific-IgE levels were also significantly less in all treated mice than in sham-treated mice ( P<0.05). Furthermore, IL-4, IL-5 and IL-13 production by PN-stimulated splenocytes in vitro from ImmuBalance fed mice were markedly reduced compared with sham-treated mice, whereas IFN-γ production was moderately increased. TGF-β and TNF-α production were similar. Conclusions ImmuBalance protects against PN-induced anaphylaxis when administered as a food supplement in this model. Protection was associated with down-regulation of Th2 responses. This supplement may provide a potential novel therapy for PNA. [ABSTRACT FROM AUTHOR]

Recent studies on crop rotation have suggested that the cultivation of mycorrhizal host crops increases the arbuscular mycorrhizal (AM) colonization of succeeding crops. A pot experiment was conducted to determine whether the positive effect of AM host cropping on the growth of succeeding maize is mainly due to the multiplication of indigenous AM fungi. Maize plants were grown in soils after mustard (non-host) cropping without AM fungal (AMF) inoculum (MDNI); with inoculum from the soil after sunflower cropping (MDISF); with sterilized inoculum (MDSI); and in the soil after sunflower (host) cropping without inoculum (SFNI). The growth of maize after mustard cropping (MDNI) was inferior to that after sunflower cropping (SFNI). The AMF inoculum from the soil after sunflower cropping (MDISF) improved the growth and AM colonization of maize, and shoot weight was increased from 17 to 49% of that in the SFNI treatment. However, the sterilized inoculum (MDSI) did not show similar effects. Similar AMF species to those increased by sunflower cropping were dominant in SFNI-treated or MDISF-treated soils following maize cropping, also indicating that the AM colonization of maize was improved by multiplied AM fungi through sunflower cropping. These results suggest that the effects of preceding crops on maize growth are at least partly due to differences in AMF density caused by various preceding crops. [Copyright &y& Elsevier]

Ion mobility measurements were made for Li+ in Ne and in N2 and Na+ in SF6 using a variable-temperature drift tube. The measurements were made by two different methods: variable-E/N method at constant T and variable-T method at constant E/N, where E, N, and T are the electric field strength, the gas number density, and the gas temperature, respectively. Two datasets were compared at the same effective temperature Teff, as calculated from the Wannier equation. For Li+ in Ne, the two datasets are put on a single curve in the range 150 K

Deals with the measurement of the mobilities of Li[sup+] ions in gaseous HCl, HBr and HI as a function of the energy parameter E/N at room temperature. Calculated mobilities of Li[sup+] ions in HCl, HBr and HI.