Assessing the Assessments: Improving Methodologies for Impact Assessment in Transboundary Watercourses

Transboundary impact assessment (TIA) has become an important environmental management tool, particularly where a project may have transboundary impacts. With the growing practice of TIA, it becomes important to consider the accuracy of the transboundary impact assessments that are being conducted. If TIA is a planning tool designed to provide a basis for making an informed decision, does it actually provide the necessary information? This paper summarizes lessons learned in pilot testing a methodology to assess the accuracy of TIAs.     

脉冲放电高能转化制备纳米粉体

综合介绍了脉冲电流通过细金属丝放电(pulsed wire discharge,PWD)制备纳米粉体的方法.讨论了影响纳米粉体,特别是晶粒尺寸的因素,以防止形成亚微米颗粒.因为达到电压峰值的丝的沉积能相当于丝的汽化能,因此,能夠计算出沉积能.随着所施加的能量增加,气体压力降低,介质气体的热扩散率增大,晶粒尺寸变小.在惰性气氛中,采用PWD工艺,由金属蒸气急冷可制备金属粉体.如果介质气体变为氧气或者氨气,就能制备氧化物、氮化物纳米粒子.要制备双金属合金、双氧化物或氮化物纳米粒子就必需采用双金属丝和不同的介质气体.采用PWD工艺,在有机气体或烟气中,能制备电磁屏蔽和导电浆料和其它用途的钝化纳米粒子.采用丝输送器而实现大量生产纳米粉体的PWD工艺一个实例证明了PWD工艺生产纳米粉体的可行性.     

The preparation of copper fine particle paste and its application as the inner electrode material of a multilayered ceramic capacitor

Well size-controlled copper fine particles (diameter: 100-300?nm) were used as the inner electrode material of multilayered ceramic capacitors (MLCCs). The particles were dispersed in terpineol to form a printing paste with 50?wt% copper particles. The MLCC precursor modules prepared by the layer-by-layer printing of copper and BaTiO(3) particles were cosintered. Detailed observation of the particles, paste, and MLCCs before and after sintering was carried out by electron microscopy. The sintering temperature of Cu-MLCC was as low as 960?°C. The permittivity of these MLCCs was successfully measured with the copper inner layers.     

Multi-objective discounted Markov decision processes with expectation and variance criteria

A multi-objective discounted Markov decision process (MDP) with expectation and variance criteria is discussed. First, difficulties in variance minimization are discussed and it is shown that variance minimization is much more difficult than the expectation optimization. Then, the multi-objective MDP with expectation and variance criteria is formulated as a multi-objective non-linear programming problem. An algorithm for finding a stationary satisfactory Pareto policy is proposed by applying the satisficing trade-off method of Nakayama. In the proposed algorithm, a decision-maker need not have a high degree of judgment and it is easy to take the balance of expectation and variance criteria and furthermore, the number of auxiliary optimization problems to be solved is quite small. Numerical examples show the efficiency of the proposed algorithm.     

Behavior of Cu nanoparticles ink under reductive calcination for fabrication of Cu conductive film

Cu nanoparticle ink was prepared from Cu nanoparticles that were coated with a gelatin layer at an average diameter of 46 nm. The Cu nanoparticle ink was applied on the polyimide substrate. Conductive films were fabricated using the Cu nanoparticle ink with a two-step annealing process consisting of oxidative pre-heating at 200 °C under 10 ppm O₂-N₂ mixed gas flow and reductive calcination at 250 °C under 3 vol.% H₂-N₂ mixed gas flow showed a low resistivity of 5 μΩ cm. The hydrolysis of the remaining gelatin layer by H₂O vapor, which was formed during the reduction of the Cu oxide by 3 vol.% H₂-N₂ mixed gas, was suggested. The results suggest the possibility of the removal of the gelatin layer without oxidative pre-heating and simultaneous sintering of Cu nanoparticles in reductive calcination.     

Effects of titanium on magnetic properties of semi-processed non-oriented electrical steel sheets

The effects of titanium inclusions on magnetic properties of non-oriented electrical steel sheets were investigated. The magnetic induction and core loss of test specimens deteriorated as the titanium content increased. Electron microscopic study revealed that the deterioration was classified into two types: one was caused in the steels containing <0.016 wt% titanium by the “pinning effects” of titanium carbonitrides on the recrystallization of cold-rolled sheets, and the other occurred in the steels containing >0.016 wt% titanium by numerous (Fe, Ti)P precipitates in both grains and grain boundaries. This revised version was published online in November 2006 with corrections to the Cover Date.     

Geo- and Hydro-Mechanical Evaluation of Slope Failure Induced by Torrential Rains in Northern-Kyushu Area,July 2009

Torrential rainfall in mid-July 2009 triggered numerous geodisasters such as slope failure and debris flow in Chugoku and Northern Kyushu areas of Japan. A number of slope failures and debris flows occurred in Yamaguchi and Fukuoka prefectures resulting in extensive damage to human life and infrastructure. One of the most serious geodisasters included a slope failure followed by debris flow at Sasaguri-machi and Fukuchi-machi, Fukuoka prefecture, Japan. This paper summarizes the results of geotechnical investigations on the geodisaster sites in Fukuoka prefecture. The geotechnical investigation included determining a series of grain size distributions, consistency limits and conducting direct box shear tests for collapsed soils collected at six disaster sites. The generation mechanisms of slope failure followed by debris flow were also investigated by analyzing the precipitation, topography, geology, and strength properties of the collapsed soils. Moreover, slope deformation and stability analyses were coupled with an unsaturated-saturated seepage analysis to investigate the slope failure mechanism. The main findings from the study are summarized as: The physical properties, such as the grain size distribution, the plastic limit and liquid limit of collapsed soils, are summarized and compared with the results of other failure slopes in the literature. The collapsed soil was characterized as being a well grained soil (the uniformity coefficient >50) and highly weathered (the ignition loss >5%), however, with regard to the liquid limit and plastic index, there were no remarkable findings. The original shear strength for collapsed soils with natural water content is relatively large and slope failure doesn't occur because the cohesion in the shear strength is induced by a suction force between the soil particles under unsaturated condition. However, water seepage into the soil induces a drastic decrease in the shear strength, which is mainly caused by a decrease in cohesion (losing suction) resulting from soil saturation. In addition, the drained/undrained condition in the shear process is also sensitive to shear strength. For example, both water seepage and the shear process with constant volume cause an approximate 30% reduction in shear strength for Fukuchi-machi and Sasaguri-machi soil samples. Therefore, the reduction of cohesive strength due to water seepage and the low permeability of the slope are the parameters which trigger geodisaster. Based on the results of slope deformation and a stability analyses which took the change in water pressure and cohesive strength into account, the geodisaster at Fukuchi-machi was simulated, it is reasonable to assume that the shallow failure near the top of slope occurred due to torrential precipitation of about 100 mm per hour which triggered a debris flow.     

Direct Measurement of Fracture Energies of Brittle Heterogeneous Materials

A noncatastrophic fracture was shown to exist in the three-point bending test with a "hard-beam" machine when an artificially cracked or notched specimen was used. In this mode of fracture the energy produced by external work was transformed completely into the effective surface energy (fracture energy) of the specimen. The energy was measured from the load-time curve for the test. The fracture energies obtained by this method for plate glass were in the range 3 to 6 × 10³ ergs cm⁻², in good agreement with results obtained by other methods. The effective fracture energies of firebrick were about one order of magnitude larger than those of glass.     

Effect of antimony surface treatment on nitrogen absorption during batch annealing of an electrical steel sheet

Nitrogen absorption is usually observed during batch-type hot-band annealing of electrical steel sheets containing aluminium. This nitrogenizing causes the deterioration of magnetic properties, such as core loss and induction. In order to prevent nitrogenizing, we investigate an antimony treatment on the hot strip surface of electrical steel sheets containing aluminium. Potassium antimonyl tartrate and colloidal antimony oxides (Sb2O5) are effective against nitrogenizing. It seems that active sites on the surface of the hot strip after pickling are covered with antimony oxides to block the adsorption of nitrogen. Magnetic properties, after cold-rolling and continuous annealing of the nitrogenizing hot band, deteriorate due to small grains near the surface whose boundaries are pinned by aluminium nitrides.