Nagoya Institute of Technology

About: Nagoya Institute of Technology is a education organization based out in Nagoya, Japan. It is known for research contribution in the topics: Thin film & Catalysis. The organization has 10766 authors who have published 19140 publications receiving 255696 citations. The organization is also known as: Nagoya Kōgyō Daigaku & Nitech.

α-Dicalcium Silicate Hydrate: Preparation, Decomposed Phase, and Its Hydration

Abstract: α-C 2 SH can be synthesized by hydrothermal treatment of lime and silicic acid for 2h at 200°C. When heated to 390-490°C, α-C 2 SH dissociates through a two-step process to form an intermediate phase plus some γ-C 2 S. This appears to be a new dicalcium silicate different from known dicalcium silicates - α, α' L , α' H , β, and γ phase - and is stable until around 900°C. At 920-960°C, all the phases are transformed to the α' L phase. The intermediate phase has high crystallinity and is stable at room temperature. 29 Si MAS NMR measurements indicate the possibility that it contains both protonated and unprotonated monosilicate anions. The intermediate phase that has passed through the α' phase at higher temperature yields β-C 2 S on cooling. The intermediate phase is highly active, and completed its hydration in 1 day (w/s = 1.0, 25°C). Among the crystalline calcium silicate hydrates with Ca/Si = 2.0, its is hillebrandite that yields β-C 2 S at the lowest temperature

Effect of Ni substitution on the microwave dielectric properties of cordierite

Abstract: Cordierite (Mg2Al4Si5O18) is one of the silicates with low dielectric constant (ɛr), which are expected for good candidate of millimeter wave dielectrics. Microwave dielectric properties of Ni substituted cordierite solid solutions; (Mg1−xNix)2Al4Si5O18 have been investigated. (Mg1−xNix)2Al4Si5O18 with no secondary phase was obtained in the compositions x range from 0 to 0.1. It was found that a very small amount of Ni substitution was effectively increased of the quality factor (Qf) value and the highest Qf value of 99,110 GHz was obtained in the composition x = 0.1. No remarkable composition dependence of the temperature coefficient of resonance frequency (τf) was observed in the range from x = 0.05 to 0.2, On the other hand, τf abruptly shifted toward negative value with increasing x from 0.3 to 0.5. The correlation between the crystal structure of cordierite and the microwave dielectric properties, particularly Qf is discussed.

Correlation Between Peak Spatial-Average SAR and Temperature Increase Due to Antennas Attached to Human Trunk

Abstract: This paper discusses the correlation between peak spatial-average specific absorption rate (SAR) and maximum temperature increase for antennas attached to the human trunk. Frequency bands considered are 150, 400, and 900 MHz, which are assigned for occupational communications. This problem is thoroughly investigated with the aid of Green's function. In particular, the effect of variation of thermal constants on the temperature increase is revealed by using one-dimensional model. Computational results suggests that one of the most dominant factors which affect the correlation between peak SAR and maximum temperature increase is blood flow in tissues. This is confirmed by considering a three-dimensional realistic human body model. Uncertainties caused by the calculation of peak SAR and the difference in the body model shape are also quantified

Current technologies for recovery of metals from industrial wastes: An overview

Abstract: Fast industrialization has increased the demand for heavy metals, on the other hand, high-grade ore natural reserves are belittling. Therefore, alternative sources of heavy metals need to be investigated. Massive amounts of industrial wastes are being generated annually. The majority is sent to landfills or to incinerators, which eventually poses environmental challenges such as ecological contamination and health hazards to living beings. Such industrial wastes contain hazardous elements of various metals (Au, Ag, Ni, Mo, Co, Cu, Zn, and Cr), whose improper disposal leads to adverse effects to human being and the environment. As a result, methods for industrial waste management such as reuse, remanufacturing, and recycling have received much attention due to the fact that they improve cost effectiveness over time and enable the metal recovery businesses to thrive profitably. The present study provides a state of art review on the current technologies existing for the recovery of precious metals from industrial wastes streams to analyse the sustainability. Among the wastes, spent petroleum catalysts, medical waste, electronic scraps, battery wastes, metal finishing industry waste, and fly ash are some of the largest industrially-generated wastes. Various metal recovery processes involve physical, chemical, and thermal characteristics of waste streams and target metals for separation and extraction. The current challenges of pyrometallurgy, modification on the hydrometallurgy, physical and chemical methods and other advanced technologies are presented in this review. The hydrometallurgical method, which involves dissolving and leaching, is a proven and successful process for recovering metals from various raw materials. Several other recovery methods have been proposed and are currently being implemented; the problem is that most of them are only successful in retrieving certain metals based on specific properties of industrial waste. The recovered metal solutions are further concentrated and purified using adsorption, cementation, chemical precipitation, ion exchange, membrane filtration and ion flotation techniques, which can also be applied to other liquid waste streams. The recovery method only makes sense if the recovery cost is much less than the value of the precious metal. The limitations placed on waste disposal and stringent environmental legislation require environmental-friendly metal recovery technologies. This review paper provides critical information that enables researchers to identify a proper method for metal recovery from different industrial wastes, and also it benefits researchers and stakeholders in determining research directions and making waste management-related decisions.

A thin polymer membrane, nano-suit, enhancing survival across the continuum between air and high vacuum

Abstract: Most multicellular organisms can only survive under atmospheric pressure. The reduced pressure of a high vacuum usually leads to rapid dehydration and death. Here we show that a simple surface modification can render multicellular organisms strongly tolerant to high vacuum. Animals that collapsed under high vacuum continued to move following exposure of their natural extracellular surface layer (or that of an artificial coat-like polysorbitan monolaurate) to an electron beam or plasma ionization (i.e., conditions known to enhance polymer formation). Transmission electron microscopic observations revealed the existence of a thin polymerized extra layer on the surface of the animal. The layer acts as a flexible “nano-suit” barrier to the passage of gases and liquids and thus protects the organism. Furthermore, the biocompatible molecule, the component of the nano-suit, was fabricated into a “biomimetic” free-standing membrane. This concept will allow biology-related fields especially to use these membranes for several applications.