Bulk precipitation and stream water chemistry data from 1993 to 2005 are used to analyze the relationship between Eurasian dust storms and nutrient deposition rates in the Kutsuki experimental forest ...(near Lake Biwa). From 2000 to 2005, atmospheric deposition, total nitrogen (TN), total phosphorus (TP) and dissolved silica (DSi) deposition rates increased by 26%, 132%, and 38%, respectively in the Kutsuki experimental forest. These TN and TP increases are associated with three seasonal factors: the increasing frequency and intensity of Eurasian spring dust events (March/April); the annual typhoon period (late August/September); and autumn/early winter (October to December) monsoons. The annual typhoon and monsoon winter periods are drivers for atmospheric TP and DSi deposition due to the correlation between the deposition and precipitation. In addition, increased spring dust deposition is a primarily driver for TN deposition changes. Increased emissions from urbanized areas in China (and likely Korea) affect the chemical properties of aerosols reaching downwind Japanese regions. Aerosol processes are responsible for increasing TN in aerosols, which are affected primarily by anthropogenic emissions. From 2000 to 2005, coal burning emissions from East Asia have contributed to an increase in TP (and possibly DSi) deposition rates. The observed increase in nutrient deposition did not noticeably impact short-term (5 year) stream water fluxes in the Kutsuki experimental forest. Due to plant uptake, the forest ecosystem retained atmospherically deposited N and P. Finally, the observed increases in nutrient deposition rates over the East China Sea and the Sea of Japan may significantly influence intra-annual net primary production. It is recommended that earth system modelling incorporate changes in atmospheric nutrient deposition rates and their impacts on the regional carbon cycle as well as aquatic and terrestrial ecosystems.
We have studied textures of the rotating superfluid 3HeaA in a single narrow cylinder by NMR measurement. In a narrow cylinder, the characteristic textures such as Mermin-Ho texture (Mermin and Ho in ...Phys. Rev. Lett. 36:594, 1976) can be formed in order to minimize the free energy of the system determined by the effect of the wall, the magnetic field, the dipole interaction, the flow of the superfluid and so on. We observed three types of NMR absorption spectra dependent on the processes used to form A-phase in a narrow cylinder. A particular texture shows a characteristic spectrum and we can determine the texture from the observed spectrum by comparing the resonance frequency of the peak in NMR spectrum with the calculated one of the spin wave mode. We present the identification and the phase diagram of textures of the rotating superfluid 3HeaA in a single narrow cylinder.
The amounts of atmospheric depositions were measured by two types of bulk deposit-samplers (BDS). One of them was a commonly used dry-type BDS mounted with a conical polyethylene (PE) funnel on a ...PE-reservoir (d-BDS). The second BDS was a wet-type BDS which was devised to evaluate the nutrient loads deposited directly from the atmosphere onto lakes, and mounted with a cylindrical funnel filled with 0.005-M H
2SO
4 at 5 cm in depth (w-BDS). The water sample in the reservoirs was collected after an appropriate time interval. As the funnel sizes of d-BDSs decreased from 20 to 9 cm in diameter, the trapping efficiencies of TN and TP increased, as measurement accuracies decreased. The efficiencies measured by w-BDSs were not affected by the funnel size in the tested range from 20 to 43 cm. Based on the data continuously measured by d-BDS
20 and w-BDS
20 mounted each with a 20 cm funnel for one year, the atmospheric deposition of TN and TP measured by d-BDS
20 were 18.1 and 0.745 kg ha
−1 y
−1, which were apparently smaller than 20.7 and 0.921 kg ha
−1 y
−1 measured by w-BDS
20. It is recommended from the results that the direct nutrient-loads from atmosphere into lakes should be evaluated on the base of the more reliable unit loads measured by a w-BDS mounted with a funnel larger than around 30 cm in diameter.
Genetic defects affecting the mitochondrial respiratory chain comprise an important cause of encephalomyopathies. Considering the structural complexity of the respiratory chain, its dual genetic ...control, and the numerous nuclear genes required for proper assembly of the enzyme complexes, the phenotypic heterogeneity is not surprising. From a neuropathological view point, application of in situ hybridization and immunohistochemistry to study the choroid plexus and brain–blood barrier in ‘prototypes’ of mitochondrial encephalopathies have revealed alterations that we think are important in the pathogenesis of central nervous system dysfunction in these disorders. As the role of the blood–cerebrospinal fluid (CSF) and brain–blood barriers in mitochondrial encephalopathies is better understood, manipulation of their functions offers promises for therapeutic interventions.
Distillation of hydrogen isotopes for polarized HD targets Ohta, T.; Bouchigny, S.; Didelez, J.-P. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2012, Letnik:
664, Številka:
1
Journal Article
Recenzirano
Odprti dostop
We have developed a new cryogenic distillation system to purify Hydrogen-Deuteride (HD) gas for polarized HD targets in LEPS experiments at SPring-8. A small amount of ortho-H
2 (
∼
0.01
%
) in the ...HD gas plays an important role in efficiently polarizing the HD target. Since there are 1–5% impurities of H
2 and D
2 in commercially available HD gases, it is necessary to purify the HD gas up to
∼
99.99
%
. The distillation system is equipped with a cryogenic distillation unit filled with many small stainless steel cells called “Heli-pack”. The distillation unit consists of a condenser part, a rectification part, and a reboiler part. The unit is kept at the temperature of 17–21
K. The Heli-pack has a large surface area that makes a good contact between gases and liquids. An amount of 5.2
mol of commercial HD gas is fed into the distillation unit. Three trials were carried out to purify the HD gas by changing temperatures (17.5
K and 20.5
K) and gas extraction speeds (1.3
ml/min and 5.2
ml/min). The extracted gas was analyzed using a gas analyzer system combining a quadrupole mass spectrometer with a gas chromatograph. One mol of HD gas with a purity better than 99.99% has been successfully obtained for the first time. The effective NTP (Number of Theoretical Plates), which is an indication of the distillation performances, is obtained to be 37.2±0.6. This value is in good agreement with a designed value of 37.9. The HD target is expected to be efficiently polarized under a well-controlled condition by adding an optimal amount of ortho-H
2 to the purified HD gas.
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