Mg/Al supported metal (Fe, Co, Ni and Cu) oxide catalysts were prepared by co-precipitation of hydrotalcite-like clay materials as precursors, calcined, and used for the ozonation reaction of phenol and oxalic acid. The reaction was carried out using the catalyst and aqueous solution of phenol or oxalic acid in an O3/O2 mixed gas-flow at 20 °C. In the ozonation of phenol, the combination of ozone and supported metal oxide catalysts was effective for the removal of total organic carbon (TOC). Also in the ozonation of oxalic acid as the main TOC component, Cu/Mg/Al catalysts showed the highest activity, followed by Ni/Mg/Al catalyst, while both Fe/Mg/Al and Co/Mg/Al catalysts were not active. Leaching of Cu and Ni, probably due to the chelation of metals by oxalic acid, was significantly observed at the beginning of the reaction. However the metal leaching disappeared at the end of the reaction possibly due to the entire consumption of oxalic acid during the reaction. The best result of oxalic acid mineralization was observed over Cu/Mg/Al catalyst calcined at 600 °C, on which least leaching of the metal was detected. Moreover, a “memory effect” of hydrotalcite accelerated the mineralization of oxalic acid over the Cu/Mg/Al catalyst; oxalate anions were captured and decomposed in the reconstituted hydrotalcite interlayer space on the surface of the Cu/Mg/Al catalyst, resulting in a remarkable enhancement in the catalytic activity of the ozonation. 相似文献
This paper describes the numerical method of a distributed parameter analysis code SPIRAL for the calculation of fluid flow and temperature in arbitrary channel geometries, discusses the numerical method in the modeling and solution of the problem, and presents some results, including comparison with experiments.
The derivation and solution of the finite element equations is discussed. In order to overcome difficulties arising from the geometry, the Galerkin finite element method using isoparametric elements was employed, and a procedure of finite element generation using curvilinear coordinate system was developed.
The SPIRAL code permits calculation of the fine structure of the multi-dimensional steady-state single-phase fluid flow and temperature fields in LMFBR fuel pin subassemblies in the presence of wire spacers. Calculated results are presented for crossflow velocity distributions and crossflow pressure drop characteristics in a tube bundle geometry with and without wire spacers, natural convection and heat transfer in horizontal annuli, flow in a wire-wrapped 7-pin bundle geometry and fully developed turbulent flow in a parallel 4-rod array contained in a rectangular duct. 相似文献
It is difficult for renewable energy resources to provide constant power with excellent quality for the grid system. This serial research proposes a power stabilization system with a pumped storage to guarantee power quality and capacity, while the outputs from the energy resources are at unstable and/or fluctuating conditions. The power stabilization system with a counter-rotating type pump-turbine unit was prepared and operated at the pumping and the turbine modes. The unit composed of the tandem impellers/runners connected to the inner and the outer armatures of the unique motor/generator. The experiments have verified that this type pump-turbine unit is reasonably effective to stabilize momentarily/instantaneously the fluctuating power from the renewable energy resources. 相似文献
We devised a threshold voltage compensation pixel circuit using back‐gate bias voltage. Variation in threshold voltages can be reduced to 10% in simulation while improving the saturation characteristics of a driving transistor. The pixel circuit can compensate not only threshold variation but also mobility variation. We fabricated a 5.29‐in Quad‐VGA organic light emitting diode display using this pixel circuit. 相似文献
Silicone gel is widely used to encapsulate power modules, and improvement of its dielectric strength has been required. So, the purpose of our research is to improve dielectric strength of silicone gel encapsulant, and we focus on crosslinking degree of silicone gel. Previous studies have shown that growth mechanism of electrical tree changes with crosslinking degree of silicone gel. This suggests the possibility that the presence of the interface by different crosslinking degrees inhibits the tree growth. In this paper, we have investigated the tree growth and breakdown characteristics in silicone gel—crosslinking degrees graded layer materials. The interfaces in our study are arrange as being vertical to the line of electric force. Consequently, it was clarified that barrier effect of interface by different crosslinking degrees and the relaxation of electric field in low crosslinking degree region retards on tree growth, which improves the dielectric strength. 相似文献
Doping effects of Pt and Ru on Ni/Mg(Al)O catalysts were compared in daily start-up and shut-down operations of steam reforming of CH4. Trace Pt-doped catalyst showed better behavior than trace Ru-doped catalyst; the former was self-activated but the latter was not, although both exhibited self-regenerative activity. Moreover, the former exhibited sustainable activity, although the latter was quickly passivated, in the autothermal reforming of CH4. Formation of Pt–Ni alloy on the surface of fine Ni metal particles on the catalysts was suggested by EXAFS analyses. CH4 was dissociatively activated to form hydrogen on Pt, assisted by adsorbed O or OH species, leading to the self-activation via Ni reduction by hydrogen spillover from Pt. The self-regeneration of the Pt–Ni/Mg(Al)O catalysts can be achieved by the continuous rebirth of active Ni metal species via reversible reduction–oxidation between Ni0 and Ni2+ in/on Mg(Ni,Al)O periclase assisted by the hydrogen spillover. 相似文献
This is a report of successful management for a far advanced, chemorefractory testicular cancer patient. A 29-year-old male was referred to our hospital for the treatment of progressive lung metastases with elevated hCG level, which had recurred after complete remission following 3 courses of BEP chemotherapy and progressed after transient partial regression following 2 courses of intensified EP chemotherapy. In addition, a 3 cm in diameter, solitary brain metastasis was detected on CT. First, we performed wedge resection of bilateral pulmonary lower lobe for chemorefractory pulmonary metastases. Histological examination revealed viable embryonal carcinoma identical to the primary one. Thereafter, whole brain irradiation in combination with VIP chemotherapy (etoposide 100 mg/m2, cisplatin 20 mg/m2 and ifosfamide 1200 mg/m2 daily for 5 consecutive days) was carried out to treat brain metastasis. By 2 cycles of VIP therapy and irradiation (36 Gy), partial tumor regression and normalization of hCG level were achieved, leading to salvage surgery of the brain metastasis which histologically proved to be necrosis. Following an additional cycle of VIP therapy, the patient has been free of recurrence 24 months after completion of the treatment. 相似文献
Boron-rich cluster compounds are studied for their potential as high-temperature thermoelectric materials with low thermal
conductivity. Two B12 icosahedra systems with attractive thermoelectric properties have recently been discovered: p-type REB44Si2 (where RE stands for rare earth) and the anomalous n-type series of RE-B-C(N) homologous compounds. Three different doping effects of these compounds were investigated in this
work in an attempt to control the properties: doping disorder into REB44Si2, which is a variable-range hopping system, V-doping of YB44Si2, and C-doping (carbon composition control) of YB28.5C4. The attempt to enhance the Seebeck coefficient in TbB44Si2 through disorder was inconclusive, while V-doping of YB44Si2 had a negative effect on the thermoelectric properties. Controlling the carbon composition of YB28.5C4 appeared to be a promising route for increasing the absolute value of the Seebeck coefficient. 相似文献