Measurement of thermal conductivity of ice slurry made from solution by transient line heat-source technique (analytical discussion on influence of latent heat of fusion)

We have been studying on ice slurry in a dynamic type ice storage system. The ice slurry has many good characteristics. The ice slurry can be made from a solution. When designing the ice storage system using this ice slurry, thermal conductivity of the ice slurry is essential.When thermal conductivity of the ice slurry made from a solution is measured by a transient line heat-source technique, a measurement value of thermal conductivity is affected by a latent heat of fusion of ice. Therefore, the thermal conductivity measured is apparent thermal conductivity. In this study, influences of Stefan number, initial concentration of the solution, initial solid fraction (initial IPF) and Fourier number on the thermal conductivity was analytically discussed to improve measurement accuracy of the thermal conductivity of ice slurry in the transient line heat-source technique.     

Material properties of solidified soil grains produced from dredged marine clay

Solidified soil grains are produced by crushing a solidified soil mass which is made of dredged soil mixed with cement. It would be beneficial if these solidified soil grains could be used as fill material instead of sand/gravel. However, the strength property of solidified soil grains has not yet been thoroughly studied. In addition, as it is well known that solidified soil tends to deteriorate in seawater due to the leaching of calcium, it is necessary to make a complete study of the deterioration properties of solidified soil grains. In the current study, the material properties of solidified soil grains have been investigated. The test results revealed that (1) the strength of normal single solidified soil grains is smaller than that of natural rock grains, (2) the internal friction angle of solidified soil grains is greater than 30°, and (3) the internal friction angle of solidified soil grains tends to decrease along with the progress of deterioration; however, deterioration will not be experienced by solidified soil grains which have unconfined compressive strength larger than approximately 14?MN/m².     

Convolutional sparse coding‐based deep random vector functional link network for distress classification of road structures

This paper presents a convolutional sparse coding (CSC)‐based deep random vector functional link network (CSDRN) for distress classification of road structures. The main contribution of this paper is the introduction of CSC into a feature extraction scheme in the distress classification. CSC can extract visual features representing characteristics of target images because it can successfully estimate optimal convolutional dictionary filters and sparse features as visual features by training from a small number of distress images. The optimal dictionaries trained from distress images have basic components of visual characteristics such as edge and line information of distress images. Furthermore, sparse feature maps estimated on the basis of the dictionaries represent both strength of the basic components and location information of regions having their components, and these maps can represent distress images. That is, sparse feature maps can extract key components from distress images that have diverse visual characteristics. Therefore, CSC‐based feature extraction is effective for training from a limited number of distress images that have diverse visual characteristics. The construction of a novel neural network, CSDRN, by the use of a combination of CSC‐based feature extraction and the DRN classifier, which can also be trained from a small dataset, is shown in this paper. Accurate distress classification is realized via the CSDRN.     

One-dimensional electrospun ceramic nanomaterials and their sensing applications

One-dimensional sensing materials that are prepared via electrospinning and controlled annealing exhibit intrinsic properties, such as electron transmissivity, magnetic susceptibility, specific heat capacity, as well as optical and mechanical characteristics. Particularly, the electronic transmission characteristics of the ceramic fiber materials, such as the electrical conductivity, photocurrent, magnetoresistance, nanocontact resistance, and dielectric properties, exhibited great potential for applications in the next generation of electronic sensing devices. First, electrospun ceramic materials with different structural and functional characteristics were reviewed here, after which the strategies for improving their properties, as well as the method for assembling the flexible devices, are summarized. Moreover, the electrospun ceramic nanofibers were detailedly discussed regarding applications in device construction and wearable electronics, such as photosensors, gas sensors, mechanical sensors, and other energy storage devices. Finally, the future development direction of the electrospinning technology for multifunctional and wearable electronics skin was proposed.     

Tacticity control by conformational isomerization in free radical polymerization of acrylate

Contribution of conformational isomerization to polymer tacticity has been studied in free radical polymerization of (−)-menthyl 2-acetamidoacrylate with azo initiators. It has been demonstrated that the chain end of the growing polymer radical, which is generated from the s-trans and s-cis conformers of monomer, produces stereoselectively new R and S configurational quaternary carbons, respectively, for the attack of monomer. In addition, polymerization reactivity of both conformers is indistinguishable under the present conditions, and the polymerization is considered to proceed through a chain-end controlled mechanism, which excludes a penultimate unit effect on tacticity in the polymerization. The results obtained would give a clue to understand an origin of tacticity in conventional free radical polymerization of acrylates.     

Development of a technique for high resolution electron microscopic observation of nano-materials at elevated temperatures

A technique for high resolution transmission electron microscopic (TEM) observation of nano-materials at very high temperatures has been developed. A spirally wound tungsten wire, normally used as the heating element of a high resolution-high temperature-specimen heating holder, was coated with a thin carbon film and the carbon film was used as the substrate of nanometer-sized specimen. The carbon film was securely self-adhered on the heater and the form of the carbon film remained unchanged until the tungsten heater is heated to around 1173 K. Temperature distribution on the carbon film has been measured by observing the sublimation of ZnS particles. Behavior of gold atoms on a surface of gold nano-particles dispersed on the carbon film has been clearly observed at 773 K in a scanning transmission electron microscope (STEM).     

A water-soluble,reciprocity-law-failing photoresist

For the purpose of obtaining a water-soluble, reciprocity-law-failing photoresist, a study was made on the photo-crosslinking properties of various systems composed of water-soluble polymers and bisazides. Reciprocity-law-failing photoresists are suitable for use in the fabrication of black matrix color picture tubes without any alteration in the shadow mask. As a result, a system containing polyvinylpyrrolidone, polyacrylamide, and 4, 4′-diazidostilbene-2, 2′-disulfonic acid disodium salt was found to show a significant reciprocity-law-failing property in the range of light intensity used practically in black matrix fabrication. The mechanism of the photo-cresslinking reaction of this photoresist was investigated. It is suggested that the bisazide decomposes to liberate a reactive dinitrene intermediate. This photodecomposition was found to proceed reciprocally. The nitrene reacts with polymer molecules to form a water-insoluble three dimensional network. If, however, oxygen is present, this crosslinking reaction is inhibited by a preferential reaction between dinitrene and oxygen. By this oxygen effect, this photoresist reveals significant reciprocity-law-failing characteristics.     

The E3 Ubiquitin-Protein Ligase RNF4 Promotes TNF-α-Induced Cell Death Triggered by RIPK1

Receptor-interacting protein kinase 1 (RIPK1) is a key component of the tumor necrosis factor (TNF) receptor signaling complex that regulates both pro- and anti-apoptotic signaling. The reciprocal functions of RIPK1 in TNF signaling are determined by the state of the posttranslational modifications (PTMs) of RIPK1. However, the underlying mechanisms associated with the PTMs of RIPK1 are unclear. In this study, we found that RING finger protein 4 (RNF4), a RING finger E3 ubiquitin ligase, is required for the RIPK1 autophosphorylation and subsequent cell death. It has been reported that RNF4 negatively regulates TNF-α-induced activation of the nuclear factor-κB (NF-κB) through downregulation of transforming growth factor β-activated kinase 1 (TAK1) activity, indicating the possibility that RNF4-mediated TAK1 suppression results in enhanced sensitivity to cell death. However, interestingly, RNF4 was needed to induce RIPK1-mediated cell death even in the absence of TAK1, suggesting that RNF4 can promote RIPK1-mediated cell death without suppressing the TAK1 activity. Thus, these observations reveal the existence of a novel mechanism whereby RNF4 promotes the autophosphorylation of RIPK1, which provides a novel insight into the molecular basis for the PTMs of RIPK1.