We investigated the adsorption behavior of molecular contaminants onto the different models of Si(100) wafer surface by the quantum molecular dynamics. In this study, we chose two models of Si(100) wafer, such as the hydrogen-terminated surface and the oxide surface. Also, the adsorption of airborne molecular contaminants, such as Docosahexapentadecan (D5), dibutyl phthalate (DBP) and dioctyl phthalate (DOP) which were detected in the environment to manufacture the semiconductor devices, were estimated and compared. And ammonia (NH_3), benzene (C_6H_6), water (H_2O) as comparative materials were chosen. As the results, it was confirmed that the charge distribution in the oxide surface was bigger than the charge distribution in the hydrogen-terminated surface. We showed the adsorption behavior of each molecular contaminant onto the wafer surface visually. It was showed that the different charge distribution influenced an adsorption condition in the room temperature.

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In recent years, the sterilization and physiological effectiveness of charged particles in indoor environment have attracted much attention, and various households electrical appliances with built-in ion generators have been released. However, the physiological influence of negative charged ions in indoor air environment is not precisely understood, and many aspects concerning the convection, diffusion properties and residence time of negative charged particles emitted into indoor air remain unknown. In particular, there are almost no case studies of methods for predicting concentration levels and its distributions by developing detailed transport phenomenon models for charged particles to analyze the behavior of these in indoor environments or architectural fields. Toward this end, the overarching goal of this work is to develop the numerical method that reproduces the transportation of negative/positive charged ions in indoor air. The numerical models are based on fundamental physicochemical and electrical principles. To be more precise, electrophoretic migration model, wall surface deposition model based on molecular diffusion and electrophoretic migration, and uni-molecular and bi-molecular reaction model of negative and positive charged particles were proposed. The coupled analysis of CFD and proposed numerical transportation models of charged particles were carried out to aim at 3-dimensional cylinder type duct model. This paper reports two topics. The first is the outline of negativee charged ions concentration decay experiment in the cylinder type test chamber and estimation results of reaction probability a depositing to different surface materials. The reaction probability of cluster ions depositing to electrically conductive surface was assumed to an order of 10^<-4>[-]. The second topic is numerical prediction corresponding to the experimental setup and the results of numerical simulation for transport phenomena of negative charged particles were in reasonable agreement with the experimental results.

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By utilizing the relatively stable temperature of groundwater, groundwater heat pump (GWHP) systems can achieve a higher coefficient of performance and can save more energy than conventional air-source heat pump (ASHP) systems. However, it is difficult for only ground heat source to meet the heating and cooling loads with an annual balance. In order to optimize the operation of GWHP systems, it is necessary to develop a system using both groundwater and air sources according to the condition of building loads and temperature. Furthermore, groundwater should be used only as a heat source by recharging in one or two wells to prevent the subsidence and save the boring cost. This research has developed a GWHP system that employs a hybrid heat pump system with groundwater wells using multi heat source, groundwater and air source. In this paper, several case-studies were conducted to predict an annual performance of the developed system on the various conditions, such as location of introduction, type of refrigerant, and capacity of pump. As a result, the system APF in base case, which is using a refrigerant of R410A and a pump of 0.8kW in Tokyo, was calculated as 5.24. Moreover, the developed hybrid system on the each condition achieved the improved APF by 4 to 17% compared to using only air as heat source.

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