The improvement of the mechanical stability and leachability of bituminized waste form of radioactive ash by addition of reused polyethylene

This study was carried out in order to produce bituminized waste forms, which have dimensional and mechanical stability like cement-based waste forms. This paper reports the effects of adding polyethylene (PE) to the bituminized waste form. The additive used for the experiment was the spent PE generated from agricultural use. The bitumen used in the sample preparation is straight-run distillation bitumen of penetration 60/70 (paving asphalt). The waste used for the experiment was a bottom ash generated from an industrial (inactive) waste incinerator. Bituminized waste forms with PE contents of 5 wt% or more resulted in maintaining dimensional and mechanical stability. The compressive strength and softening point of bituminized waste forms increase in proportion to the amount of additional PE. The leaching test using ANS 16.1 shows that the principal leaching mechanism of elements (Cs, Sr, Co) from bituminized waste forms is diffusion. Furthermore, it is demonstrated that additive PE of 5-10 wt% does not change the leaching mechanism, and bituminized waste forms maintain a high leach resistance.     

国际正渗透膜技术研讨会IFOS2016回顾：正渗透可行吗?

回顾了2016年底在悉尼召开的国际正渗透研讨会的主要内容,概括了近年来正渗透技术研究和应用的最新进展。在膜材料方面,提高水通量应着重于降低支撑层结构参数,而不是提高分离层的渗透性能。提高分离层的截留率和耐污染性是提高膜性能的关键。对于各种类型的驱动溶质而言,无机盐很可能是最为现实可靠的驱动溶质。正渗透技术在渗透稀释和与其他分离技术的耦合过程处理高含盐污染水源中有潜在应用,然而渗透能发电在短期很难成为主流的新兴能源。     

Properties and rapid consolidation of nanostructured Al2O3-Al2SiO5 composites by high frequency induction heated sintering

The rapid sintering of nanostructured Al₂O₃ and Al₂O₃ to Al₂SiO₅ composites was investigated by a high-frequency induction heating sintering process. The advantage of this process is that it allows very quick densification to near theoretical density and inhibition of grain growth. Highly dense nanostructured Al₂O₃ and Al₂O₃ to Al₂SiO₅ composites were produced with simultaneous application of a 80 MPa pressure and induced output current of a total power capacity (15 kW) within 3 min. The sintering behavior, grain size and mechanical properties of Al₂O₃ and Al₂O₃ to Al₂SiO₅ composites were investigated.     

Rapid sintering of ultra-fine WC-10 wt% Co by high-frequency induction heating

High-frequency induction-heated sintering (HFIHS) is utilized to consolidate ultra-fine grain WC-10 wt% Co. Densification to near theoretical density in a relatively short time can be accomplished with insignificant change in grain size. WC-10 wt.% Co with a relative density of up to 99.5% was produced within 1 min with the simultaneous application of 60 MPa pressure. The average grain size of the densified material was about 260 nm and the mean free path in the cemented carbide was about 11 nm. The sintered material had fracture toughness and hardness values of 13 MPa^.m^1/2 and 1886 kg/mm², respectively. The hardness is comparable to literature values but the fracture toughness is about two times higher. These results are interpreted in terms of current effects on sintering and mass transport. Higher heating rates result in higher density with smaller WC grain size, and higher current-induced solubility of WC in Co is proposed as an explanation for the high fracture toughness.     

Factors influencing smartphone use and dependency in South Korea

This study examined the factors affecting the South Korean people’s use of smartphones within the framework of the technology acceptance model (TAM). Using an in-person survey (N = 852), the study confirmed the propositions of the TAM. The study also included individuals’ psychological antecedents, such as motivations for social inclusion and instrumental use of smartphones, innovativeness, behavioral activation system (BAS), and locus of control. While the motivations and innovativeness verified previous studies’ findings, BAS and locus of control demonstrated their unique contributions to explaining smartphone use. Smartphone dependency was also affected by the antecedents in the use of smartphones.     

Antioxidant and anti-adipogenic activities of persimmon tannins

Soluble and insoluble tannins from 5 different types of persimmon-unripe, astringent Cheongdobansi (CU); red-ripe Cheongdobansi (CR); unripe, astringent Daebong (DU); red-ripe Daebong (DR); and unripe, non-astringent Fuyu (FU)-were prepared. The antioxidant activity of the tannins was determined by measuring the DPPH radical scavenging activity (RSA), ABTS RSA, and reducing power. The strongest DPPH RSA and reducing power were found in the soluble tannins from CU. Soluble tannins from CR, CU, and DU at a concentration of 1,000 μg/mL scavenged most of the ABTS radicals. Approximately 83 and 42% suppression of adipogenesis in 3T3-L1 cells were observed in the 100 μg/mL treatments of the soluble tannins from CU and CR, respectively. Soluble tannins showed relatively higher antioxidant and anti-adipogenic activities than insoluble tannins. These results demonstrate that soluble and insoluble persimmon tannins showed different antioxidant and anti-adipogenic activities according to persimmon types.     

Design and implementation of a wireless sensor network architecture using smart mobile devices

Wireless sensor networks improve the quality of human daily life like ubiquitous city and healthcare services as well as the fundamental monitoring such as environment pollution, tunnel monitoring, earthquake diagnostic, and so on. To increase usability and feasibility of collected sensor data, a wireless sensor network should be required to apply a variety of mobile devices to give the information at anytime and anywhere to users. Thus, we present multi-sensor centric smart sensor network architecture using general mobile devices in order to provide more efficient and valuable sensor network application and services. The proposed system architecture is based on IEEE 802.15.4-2006 standard with smart mobile devices. We also show some scenarios with on-demand request and real time event driven data to show the feasibility of the proposed architecture using five kinds of sensors such as magnetic, photodiode, microphone, motion and vibration. Based on the experiment results, we show that the proposed system has the potential as smart mobile device-based wireless sensor network architecture.     

A study of the oxidation behavior and the postannealing effect in a graded SiGe/Si heterostructure

A study on the dry thermal oxidation of a graded SiGe layer was performed. To reduce the Ge pileup effect during the thermal oxidation, the SiGe layer was deposited with much lower Ge content near the free surface than near the SiGe/Si heterointerface. After dry thermal oxidation at 900°C, the Ge composition in the pileup layer was significantly reduced and strain relaxation by defect formation was prevented due to the graded Ge distribution. To homogenize the Ge distribution between the pileup layer and remaining SiGe layer, the oxidized layers were postannealed. The homogenization is significantly enhanced by strain-induced diffusion, and it was confirmed by uphill diffusion of Ge. This result can propose an alternative oxidation method of strained SiGe/Si heterostructures.     

mu-Conotoxin PIIIA, a new peptide for discriminating among tetrodotoxin-sensitive Na channel subtypes

We report the characterization of a new sodium channel blocker, mu-conotoxin PIIIA(mu-PIIIA). The peptide has been synthesized chemically and its disulfide bridging pattern determined. The structure of the new peptide is: [sequence: see text] where Z = pyroglutamate and O = 4-trans-hydroxyproline. We demonstrate that Arginine-14 (Arg14) is a key residue; substitution by alanine significantly decreases affinity and results in a toxin unable to block channel conductance completely. Thus, like all toxins that block at Site I, mu-PIIIA has a critical guanidinium group. This peptide is of exceptional interest because, unlike the previously characterized mu-conotoxin GIIIA (mu-GIIIA), it irreversibly blocks amphibian muscle Na channels, providing a useful tool for synaptic electrophysiology. Furthermore, the discovery of mu-PIIIA permits the resolution of tetrodotoxin-sensitive sodium channels into three categories: (1) sensitive to mu-PIIIA and mu-conotoxin GIIIA, (2) sensitive to mu-PIIIA but not to mu-GIIIA, and (3) resistant to mu-PIIIA and mu-GIIIA (examples in each category are skeletal muscle, rat brain Type II, and many mammalian CNS subtypes, respectively). Thus, mu-conotoxin PIIIA provides a key for further discriminating pharmacologically among different sodium channel subtypes.