Estimation of heat rejection based on the air conditioner use time and its mitigation from buildings in Taipei City

The main work in the research focuses on the analysis and mitigation of the anthropogenic heat discharged from buildings, which is one of the main reasons leading to the heat island effect. The residential and commercial buildings, divided into 10 categories, with HVAC systems were analyzed by the building energy program, EnergyPlus. With the help of GIS, the heat rejection of all the residential and commercial buildings in DaAn Ward of Taipei City were evaluated, in which the spatial data and diurnal variation of the heat rejection were described by 3-h time periods. Furthermore, the effect of mitigation strategies was discussed. The first strategy was to change the wall/roof material of building envelope. The second and third strategies, from the viewpoint of energy saving, were to change the temperature setting of air conditioners and to turn off the lighting and equipment when not in use. The fourth strategy was to use a better efficiency of the cooling systems. Finally, the evaluation of installing the water-cooled cooling system, which discharges heat in the form of sensible and latent heat, was also included.     

The feedback of heat rejection to air conditioning load during the nighttime in subtropical climate

Taipei City, located in the subtropical zone, has a basin landform. The summer is always hot and humid and the air temperature right after sunset is typically higher than 30 °C. Heat rejection from residential buildings in urban area, equipped with lots of the window type air conditioners, not only increases the air temperature outside, but also burdens the cooling load. Based on the time schedule of air conditioner use of Taipei citizens, the heat rejection/building energy use and the air temperature distribution were evaluated, and finally the additional electric consumption of air conditioners was predicted. Two software, EnergyPlus (building energy program) and Windperfect (CFD, computational fluid dynamics software) were employed in this study. In the CFD simulation, the geometry of buildings that covers 700 m in diameter was created with GIS (geographical information system) and the total mesh number was more than 3 millions. Three specified temperatures (T_am, T_bu and T_ac) were used to describe the temperature distribution within the urban canopy by hourly time variation and spatial distribution with height and horizontal profile. The results revealed that the temperature gradually increased with height and the temperature next to the buildings was always higher than the ambient air. The feedback (penalty) of heat rejection to cooling load was found 10.7% during 19:01 to 02:00 h on the following day.     

Nitrogen desorption from pure iron melts under reduced pressure

More recently, lower nitrogen contents of steel are required in view of its workability and applicability. The present study covers basic investigations on the improvement of mass transfer in denitrogenation of steel melts under vacuum. Extensive reduction of the contents of the surface-active elements oxygen and sulfur is a precondition to increase the rate of nitrogen desorption. Kinetics of nitrogen transfer is reliably described by a mixed control model which includes diffusion in the melt, interfacial reaction and diffusion in the gas phase. Particularly at low oxygen and sulfur contents, mass transfer of nitrogen during desorption from steel melts is markedly accelerated. A convincing explanation of this phenomenon has not been found yet.     

FT-IR studies of decarbonylation and recarbonylation of [Pt3(CO)6] 5 2− supported on dehydrated SiO2

Decarbonylation of [Pt₃(CO)₆]₅ on SiO₂ at 373 K produced [Pt₃(t-CO)₃]₅ species, where all the terminal CO remained. Complete decarbonylation at 423 K was not observed, which led to aggregation at 473 K. The interaction of some Pt with SiO₂ inhibited complete recarbonylation to [Pt₃(CO)₆]₅.     

Nanoarchitectonics for Controlling the Number of Dopant Atoms in Solid Electrolyte Nanodots

Controlling movements of electrons and holes is the key task in developing today's highly sophisticated information society. As transistors reach their physical limits, the semiconductor industry is seeking the next alternative to sustain its economy and to unfold a new era of human civilization. In this context, a completely new information token, i.e., ions instead of electrons, is promising. The current trend in solid‐state nanoionics for applications in energy storage, sensing, and brain‐type information processing, requires the ability to control the properties of matter at the ultimate atomic scale. Here, a conceptually novel nanoarchitectonic strategy is proposed for controlling the number of dopant atoms in a solid electrolyte to obtain discrete electrical properties. Using α‐Ag_2+δS nanodots with a finite number of nonstoichiometry excess dopants as a model system, a theory matched with experiments is presented that reveals the role of physical parameters, namely, the separation between electrochemical energy levels and the cohesive energy, underlying atomic‐scale manipulation of dopants in nanodots. This strategy can be applied to different nanoscale materials as their properties strongly depend on the number of doping atoms/ions, and has the potential to create a new paradigm based on controlled single atom/ion transfer.     

Segmentation of abnormal liver region based on earth mover’s distance between histograms with mapping of the distances by multidimensional scaling

In this paper, we propose using earth mover’s distance (EMD) to obtain the appropriate similarity between each histogram for segmentation of abnormal liver regions with mapping of the distances by multidimensional scaling. Conventionally, the similarity between each histogram is calculated by integrating the difference between each bin of the histograms. However, this similarity is unsuitable for appropriate comparison of the histograms because the number of bins for calculating the local histograms of computed tomography images varies. We used EMD to resolve this problem regarding the difference in bin numbers, and the obtained distances are used for mapping the local histograms by multidimensional scaling to low-dimensional space. In the low-dimensional space, the abnormal liver region was well segmented by support vector machine in the test datasets.     

Real-Space Imaging of Chain Polymerization Initiated by a Scanning Tunneling Microscope Tip

Initiation and termination of chain polymerization of amphiphilic diacetylene compounds in a monomolecular layer on a graphite substrate were observed and controlled at nanometer scale using a scanning tunneling microscope (STM). A polydiacetylene molecule of a desired length, which has a unique molecular conformation, can be created at desired positions.     

Low-Temperature Structural Phase Transition in ZrO2–12 mol% CeO2 Studied by Infrared Spectroscopy and X-ray Diffractometry

The low-temperature tetragonal ( t ) to monoclinic ( m ) phase transition in ZrO₂–12 mol% CeO₂ was studied by Fourier-transform infrared spectroscopy and X-ray diffractometry (XRD). When the ZrO₂–12 mol% CeO₂ was cooled, the t → m phase transition occurred at about 120 K; this caused significant changes in the infrared reflectance spectra and X-ray diffractograms. As the phase transition proceeded, "difference spectra" obtained by subtracting the infrared spectra before and after the phase transition revealed two infrared modes at 575 and 740 cm⁻¹ which were assigned to the m phase. The volume fraction of the m phase (determined by XRD) and the subtraction coefficient (defined such that the difference spectra reproduced the infrared spectrum of m -ZrO₂) were consistent with each other; this revealed a marked discontinuity at about 120 K. Full width at half maximum of the ( 1 11) _m and (111) _t reflections also indicated a similar discontinuity at about 120 K.     

Effect of (−)N-[α-phenyl-β-(p-tolyl)ethyl] linoleamide on lipid levels in serum and liver in cholesterol-fed rats

The effect of (−)N-[α-phenyl-β-(p-tolyl) ethyl] linoleamide (PTLA) on lipid levels in serum and liver was compared with that of sitosterols in rats maintained on a diet supplemented with 1% of cholesterol, 0.5% of ox bile extracts, and 10% of hydrogenated coconut oil for 8 weeks. When PTLA was added to the diet at a level of 0.1%, the mean liver cholesterol level of male rats was reduced to 41% of the control and that of female rats was reduced to 19% of the control. In female rats, which showed higher cholesterol levels in serum and liver than male rats after cholesterol feeding, PTLA lowered the liver cholesterol level even at 0.0008% in the diet. Serum cholesterol was lowered by PTLA but not so markedly as liver cholesterol. The inhibition of cholesterol deposition in the liver suggests that the interference with cholesterol absorption is one of the main actions of PTLA. Sitosterols showed a similar pattern of lipid-lowering action, but the potency was far less than that of PTLA.