Estimation and comparison of nitrogen loads and attenuation in agricultural catchments of Japan and Korea.

To help in clarifying the relationship between the time lag and attenuation of nitrogen (N) loads generated in agricultural catchments, long-term trends in activities that generate N loads and in environmental N loads were estimated in catchments in Japan and Korea dominated by non-point-source emissions. Our approach used statistical data and geographical information system software to analyze pollutant loads. The method was successful in both countries because of the availability of well-developed statistics, geographical information, and weather and water quality monitoring systems, and the accumulation of research data concerning the generation of N loads and the fate of N in soils. Comparison of environmental loads with the loads observed in river water at the outlet of each catchment revealed that: (1) the effect of changes in the environmental load in a catchment appeared almost immediately in the river water quality in Korea, but did not appear clearly even 10 years later in Japan; and (2) the strength of the attenuation appeared to be much lower in Korea than in Japan. These findings suggest that regional characteristics play important roles in the sensitivity of water quality to load-generating activities.     

Analysis of water in oil-impregnated kraft paper and its effect onconductivity

Oil impregnated paper or polymer film is the main insulating system for many kinds of power apparatus. The oil impregnated materials, especially oil impregnated kraft paper, include a significant amount of water, and this water disturbs the insulating performance of the devices. The amount of water in the materials usually is represented by the difference in weight between the normal material and the same material after drying. However it is difficult to measure the absolute value of the water content and to determine the state in which the water exists in the materials. In this study, we examined the IR spectra of water in oil impregnated kraft paper, because the IR spectrum of the water indicates not only the amount of water but also its state. It was found that most of the water behaves as liquid water, and some as hydrogen bonded water, interacting with the paper fiber. The dc conductivity of the kraft paper depends only on the amount and state of the water associated with it whether or not the paper is impregnated with the oil     

State of water in hydrocarbon liquids and its effect onconductivity [transformer oil]

The humidity or the dissolved water in insulating oils influences conduction and breakdown phenomena. The corrections between the amount of dissolved water and the electrical properties have been investigated. However, the effect of water has been based only on the total amount of water because in the past there was no way to observe the state of water in oil in an electrical field. With the availability of Fourier transform infrared (FTIR) spectroscopy to characterize water clusters, the effect of water in transformer oil can be reassessed based not only on the amount of water, but also on the state of water. In this paper, IR spectra of water in several liquid hydrocarbons and conduction current were measured at the same time. The selection of the liquid hydrocarbons was made on the basis of the degree of polarizability of the liquids. Because the water molecules combine with the polar structures by hydrogen bonding, the state of water depends on the polarizability of the oil. As a result, there is a difference in conduction phenomena depending on whether water is free or combined with the polar structure of the liquid     

Predicting nitrogen leaching with the modified LEACHM model: validation in soils receiving long-term application of animal manure composts

A variety of process-based models have been developed for predicting nitrogen (N) dynamics in agro-ecosystem; however, no reliable models have been validated for N leaching from soils receiving a long-term application of different types of animal manure composts. The Leaching Estimation and Chemistry Model (LEACHM) was recently modified by incorporating the basic structure of Rothamsted Carbon Model for extending its ability to describe soil organic matter decomposition and subsequent N leaching in soils rich in organic matter. We evaluate the applicability of the modified LEACHM in cropped Yellow soils receiving 10-year application of cattle or swine manure compost in addition to chemical fertilizers, where high-frequency field monitoring data of soil water contents, soil N contents and leachate N concentrations were available for the last 3 years. Particular attention was paid to determine all input parameters from independent measurements, parameterization from known soil properties or databases without optimisation to fit the measured field data. The model reasonably predicted temporal changes in the soil NH₄-N and NO₃-N contents, and inorganic N concentrations in the leachate as well as their differences due to different manure compost/chemical fertilizer applications. The simulations of leached N concentration yielded a Willmott index of agreement (IA) of 0.62–0.68, with those for soil moisture, soil nitrate content and crop N uptake all within an acceptable IA range. In view of the good performance without site-specific calibrations, the modified LEACHM appears to be a valuable tool for predicting N leaching from cropped soils receiving long-term manure compost applications.     

Magnetic field measurement of large aperture FFAG magnet for muon-phase-rotation ring

The PRISM-FFAG ring, which consists of 10 scaling-radial-sector magnets, has been designed to store muons with large emittance and momentum spread. The FFAG magnets differ from conventional dipole magnets in that they have a magnetic field that varies strongly with radius and the vertical direction of the magnetic field alternates. Each magnet is composed of three sets of coils to produce a defocussing (outward bending)-focussing-defocussing triplet. After careful design, the PRISM-FFAG magnets were constructed and magnetic field measurements were made. The field maps in the fiducial volume show satisfactory agreement with the design fields based on OPERA 3D/TOSCA calculations.     

Estimation of Zn and Cu unit output loads from animal husbandry facilities

Zinc (Zn) and copper (Cu) are toxic to aquatic organisms at very low concentrations that do not affect humans. We measured the daily output of Zn and Cu in wastewater from livestock farms to aquatic environments because waste from animal husbandry operations contains high levels of Zn and Cu. At most pig farms in Japan, a mixture of urine, some faeces, and service water is treated in onsite wastewater treatment facilities and discharged into a water body. Some dairy farms also have wastewater treatment facilities. We surveyed 21 pig farms and six dairy farms. The unit (i.e., per head) output load from piggery wastewater treatment facilities ranged from 0.13 to 17.8 mg/head/d for Zn and from 0.15 to 9.4 mg/head/d for Cu. Over 70% of pig farms had unit output loads of Zn and Cu below 6 and 2 mg/head/d, respectively. For dairy farms, the unit output load from wastewater treatment facilities was estimated at 1.8-3.6 mg/head/d for Zn and 0.6 mg/head/d for Cu. The unit output load for Zn from piggery wastewater treatment facilities was similar to that from treatment facilities for human waste. However, pig farms generally raise several thousand to tens of thousands of pigs; pig farms are therefore presumed to be a significant point source of Zn in rural areas.