Hydrogel photocatalysts for efficient energy conversion and environmental treatment

Photocatalysts have attracted great research interest owing to their excellent properties and potential for simultaneously addressing challenges related to energy needs and environmental pollution. Photocatalytic particles need to be in contact with their respective media to exhibit efficient photocatalytic performances. However, it is difficult to separate nanometer-sized photocatalytic materials from reaction media later, which may lead to secondary pollution and a poor recycling performance. Hydrogel photocatalysts with a three-dimensional (3D) network structures are promising support materials for photocatalysts based on features such as high specific surface areas and adsorption capacities and good environmental compatibility. In this review, hydrogel photocatalysts are classified into two different categories depending on their elemental composition and recent progresses in the methods for preparing hydrogel photocatalysts are summarized. Moreover, current applications of hydrogel photocatalysts in energy conversion and environmental remediation are reviewed. Furthermore, a comprehensive outlook and highlight future challenges in the development of hydrogel photocatalysts are presented.     

One-step phenol production from a water–toluene mixture using radio frequency in-liquid plasma

The objectives of this research were to understand the process of converting toluene into phenol in a one-step process directly from a water–toluene mixture using the plasma in-liquid method.Experiments were conducted using 27.12 MHz radio frequency(RF) in-liquid plasma to decompose a solution of 30% toluene. Based on the experimental results as evaluated using gas chromatography–mass spectrometry(GC–MS), along with additional analysis by the Gaussian calculation, density functional theory(DFT) hybrid exchange–correlational functional(B3LYP)and 6-311 G basis, the phenol generated from toluene was quantified including any by-products.In the experiment, it was found that OH radicals from water molecules produced using RF inliquid plasma play a significant role in the chemical reaction with toluene. The experimental results suggest that phenol can be directly produced from a water–toluene mixture. The maximum phenol yields were 0.0013% and 0.0038% for irradiation times of 30s and 60s,respectively, at 120 W.     

EFFECTS OF DIETARY PLANT CEREBROSIDE ON GENE EXPRESSION IN THE LARGE INTESTINE OF 1,2-DIMETHYLHYDRAZINE (DMH)-TREATED MICE DETERMINED BY DNA MICROARRAY ANALYSIS

The effects of dietary plant cerebroside on colon gene expression by DNA microarray analysis in 1,2-dimethylhydrazine (DMH)-treated mice were investigated. After 9 weeks of feeding with DMH, decreases and increases in the levels of expression of 110 and 145 genes were detected, respectively. Especially, the expression of Soggy-1, which suppresses the Wnt signaling pathway, was increased, while that of Ras-associated protein, which induces the mitogen-activated protein (MAP)-kinase pathway and is responsible for the development of aberrant crypt foci (ACF), was decreased. The results of the present study indicated that dietary cerebroside in DMH-treated mice regulates the Wnt signaling and MAP-kinase pathways, and prevents the development of ACF in the large intestine.

PRACTICAL APPLICATIONS

Dietary plant cerebroside increased expression of Soggy-1 mRNA, which suppresses the Wnt signaling pathway, and decreased expression ofRas-associated protein, which induces the MAP-kinase pathway in 1,2-dimethylhydrazine (DMH)-treated mice. The results of the present study indicated that dietary cerebroside in DMH-treated mice regulates the Wnt signaling and MAP-kinase pathways, and prevents the development of aberrant crypt foci in the large intestine, thus being of potential use for nutraceutical applications.     

High-pressure synthesis of diamond from phenolic resin

Two kinds of phenolic resin, novolak and resols, have been studied with an addition of cobalt at pressures between 2 and 4 GPa and at temperatures from 1300 to 1900 °C, all under thermodynamically graphite-stable conditions. Diamond was synthesized from these resins which had been pre-fired at 500–1000 °C. From such resins, carbon precursors carrying a great number of radicals, being nearly free of hydrogen and oxygen, and turbostratic in structure, can be constructed. The pressure–temperature conditions suitable for the diamond synthesis were dependent on the pre-firing temperatures. The cobalt served as a catalyst–solvent, similar to the case of conventional diamond synthesis from graphite under diamond-stable conditions. Well-defined single crystals cubo-octahedral in shape, measuring 0.3–0.7 mm across and classified as type Ib were obtained. This revised version was published online in November 2006 with corrections to the Cover Date.     

端铣中工具进给速度的最佳化

This paper deals with the tool feed rate optimization for smoothening of cutting force in end milling of workpiece with corner and straight parts. There is a difference between the cutting force in a corner part cutting and that in a straight part cutting. The cause of this is due to the difference in the instantaneous depths of cut in both cuttings. The scheme of this study is to prevent the generation of excessive cutting force in the corner part machining by comparison with the straight part machining. By dividing the NC (Numerical Control) cutting path of the corner part and changing the tool feed rate in each division, the cutting force in the corner part has been controlled. Furthermore, the possibility of realization of a shortening in machining time has been examined.     

Construction of the Seismic‐Analysis Technology of the Insulator Base Metals in a Single Pole Structure Disconnecting Switch

In the disconnecting switch of 300 kV or less single pole structure, the Great East Japan Earthquake received much damage at the former by the rotation insulator base metal which damage experience had. Conventionally, we carried out a simple desk evaluation about earthquake‐proof evaluation of insulator base metal. However, there is deviation with the damage actual condition and it became clear that it was an apparatus weak point part. Then, we worked on the analysis accuracy improvement of insulator base metal, and we built the analysis technology of the single pole structured disconnecting switch.     

鼻部毛囊的生物特征识别

应用Hessian矩阵的(特征值,特征向量)参数组的关系提取鼻梁的中脊线,并区分出中脊线左右二边的毛囊识别区域.然后,在Hessian矩阵特征值符号的基础上,加入最大特征值对应的特征向量的方向和梯度方向的关系作为毛囊检测的条件.在103人的数据库中,得到的识别正确率为86.26%.实验结果表明,可以把鼻部毛囊的特征识别用作高效的人体身份认证技术之一.     

CONTINUOUS COOLING OF WET FOUNDRY SAND USING A FLUIDIZED BED

Abstract

In order to establish the optimum cooling system for hot returned sand in metal casting processes, a mathematical model including simultaneous heat and mass transfer has been constructed. The present study is especially directed towards clarifying the dynamical behavior of sand cooling in a one-pass fluidized bed. A series of continuous cooling experiments has been made for various conditions. Characteristics of both transient and steady-state bed temperature are explained reasonably by the present model. Furthermore, a possible proposal has been given on the optimal operation, which raises heat exchange efficiency in fluidization cooling of hot molding sand.