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The NO x formation simulation during pulverized coal (PC) combustion has been studied for several decades. In these studies, the global reaction rate expressions for N intermediates (HCN and NH 3 ) proposed by De Soete were frequently used. Using De Soete’s expressions, the calculated reaction rates of HCN and NH 3 in the typical temperature range of 1750–2000 K for PC combustion show that HCN has obviously lower conversion rate to NO (or oxidation rate of HCN, HCN + O 2 → NO + ⋯) than that to N 2 (HCN + NO → N 2 + ⋯) as well as obviously lower conversion rate to NO than NH 3 does (NH 3 + O 2 → NO + ⋯). This is completely in contradiction with the well-recognized conclusions in the publications. Thus, in this study, the oxidation rate of HCN is recommended to be increased by about 13 times according to related literature data. The modified NO x model was integrated into coal combustion model to simulate the NO x concentration distribution for three coals (two sub-bituminous coals and one lignite) in a down-fired autothermal test furnace. The input kinetic data of coal devolatilization and char combustion for coal combustion model were all obtained from the experiments in a drop tube furnace, which ensured the good agreements of gas temperatures and compositions between prediction and measurement in the test furnace. According to the simulated results, it was nearly impossible to accurately reproduce the NO x concentration profile in pc furnace using the original De Soete’s HCN oxidation rate, since the NO x concentrations in the high-temperature flame zone were greatly underestimated. Nevertheless, a satisfactory agreement for the NO x concentration distributions between prediction and measurement could be obtained using the increased HCN oxidation rate, if proper char surface area ( S ) values were chosen. Via using different S values, it was found that the S leading to the best simulation results for three coals were all about 17.5 times higher than those measured by Hg porosimetry ( S Hg ), but they could not correlated well with that measured with low-temperature N 2 adsorption ( S BET ). This indicated that S Hg was a better surface basis for normalizing char reactivity with NO than S BET for different coals in the NO x simulation under the conditions of PC combustion.

It is important to be aware of the particle size distribution and composition of ash in coal combustion for prediction and control of ash deposition behavior, which results in the degradation of boiler performance via fouling and slagging. To elucidate fragmentation and coalescence behavior of mineral particles in a pulverized coal combustion process, char particles during the combustion reaction were sampled and analyzed for their particle size distribution and composition using a drop tube furnace. CCSEM analysis was conducted to identify included and excluded minerals in sampled char particles. Three coal samples having different char structures and ash melting temperatures were tested to estimate the effect of the physical properties of ash on fragmentation and coalescence behaviors of mineral particles. With the progress of combustion, the number of included mineral particles decreased due to their separation from char particles, leading to the increase of the number of excluded mineral particles. The total number of particles decreased with the progress of combustion. Some of particles were agglomerated, and some of them were fused to each other. These behaviors were less obvious for coal which experienced network structure of char particles during its combustion process. On the other hand, minerals in coal characterized by low melting point ash were rounded off during the coal combustion process. Fractions of included mineral were higher at smaller particle sizes, and they decreased with the progress of combustion. Elemental compositions of fused particles in coal characterized by low melting point ash are attributed to that of aluminosilicate.

Primary chest wall tumors (PCWTs) are relatively rare entities, and their clinical characteristics as well as appropriate treatments are not fully known. Previously reported studies, including ours, are reviewed here, taking into account the clinical approach and findings in Japan for the diagnosis, distribution of histological types, surgical procedures, and prognosis of these entities. Surgery for PCWTs comprised that approximately 0.7 % of surgeries in 2012 in Japan and 28.3 % of PCWTs were malignant with an extremely low rate of mortality within 30 days from surgery. Surgical biopsy is recommended for the differential diagnosis of chest wall tumors to determine if they are primary, metastatic, benign, or malignant lesions. Of the 297 PCWT cases reported in nine published studies, neurogenic tumors were the most common benign PCWT, and chondrosarcoma was the most common malignant PCWT. Reconstruction of the resected chest wall was performed for 41.3 % of cases, and the materials used were e-PTFE or polypropylene. The prognosis of patients with benign tumors is usually good if complete resection is achieved; however, the 5-year recurrence rate and disease-related mortality were approximately 22.5 and 18.1 %, respectively, for patients with malignant tumors. Surgery for PCWTs is safe; however, surgical treatment for patients with malignant PCWTs remains challenging, and multimodal treatments for each histological tumor type should be considered.

As one of the most attractive technologies for carbon capture, oxy-fuel combustion of coal has been studied worldwide. Some important results of fundamental studies and practical systems of oxy-fuel combustion are introduced in this chapter. According to the results of fundamental experiments, a slower flame propagation velocity in a O2/CO2 atmosphere requires a higher O2 concentration to obtain a stable combustion in oxy-fuel mode compared to air mode. CO2 and H2O gasification each have effects on reducing the char particle temperature and increasing the char consumption rate. In oxy-fuel mode, gasification reactions between char and CO2 or H2O can result in a high devolatilization rate and a clearly different char structure. As with simulations of heat transfer in the boiler for oxy-fuel combustion, the new weighted sum of gray-gases model for calculating gas radiation properties should be developed to adapt to very high concentrations of CO2 and H2O in the flue gas. However, particle radiation generally plays a more important role than gas radiation. Computational fluid dynamics simulation data obtained with the Callide furnace have shown an oxy-fuel combustion of 27 vol.% O2 with flue gas recycling to have a similar heat absorption to air combustion. Fundamental and applications research are still required, however, to optimize boiler design and system configurations. Keywords: Oxy-fuel; combustion; coal; boiler; heat transfer; ignition; modelling; computational fluid dynamics

We demonstrate a simple and precise measurement system of dynamic displacement for more-than-10-MHz high-frequency vibration. An interferometer using high-frequency phase modulation and simple data processing achieved a small error of better than 0.7 nm.

Fractal pore models, gas molecular movement models, and reaction models are combined to simulate char oxidation in char pores. The numerical results show the relationship between the pore structure and the apparent char reaction parameters. A modulus number φ is introduced to characterize the diffusion properties in fractal porous media with a relationship given for the apparent reaction parameter in terms of φ. The results show that the char combustion process is strongly impacted by the pore structure, and that the fractal dimension is an important parameter that should be considered in char combustion. Comparison with experimental data shows that this model is more accurate than the classical intrinsic combustion model.

In patch testing, delayed reactions at day 7 or later are regarded as “late reactions”.1 Neomycin, corticosteroids, paraphenylendiamin and gold are well-known allergens of late reactions.1,2 Of these, reactions to gold sodium thiosulfate (GSTS) can be significantly delayed, and some cases have been reported to be accompanied with granulomatous changes.3,4 Clinical reports of this reaction to GSTS are very limited. Here, we report a case of granulomatous reaction to GSTS, and we review the literature to reveal the features of this phenomenon. This article is protected by copyright. All rights reserved.

Hypersensitivity to Helicobacter pylori , a bacterium in the stomach, is induced during eradication therapy, resulting in skin manifestations. extracellular vesicles-mediated antigen presentation could play a role in this process.

In recent years, cases of IgG/IgA pemphigus, a rare subtype of pemphigus characterized by circulating IgG and IgA autoantibodies against the keratinocyte cell surface have been reported.1-6 The cutaneous manifestations of IgG/IgA pemphigus were reported to resemble those of IgA pemphigus in form, including the presence of pustules and annular lesions.1 However, no consensus on what eruptions are typical of IgG/IgA pemphigus has been established, due to the rarity of this disease. In this report, we describe a case of IgG/IgA pemphigus who developed severe crusted lesions on the seborrheic area that closely resembled facial crusted impetigo. This article is protected by copyright. All rights reserved.

Plasma cell cheilitis (PCC) is an uncommon disorder that clinically manifests as erosive or erythematous eruptions on the labial mucosa [1]. Histopathologically, dense plasma cell infiltrates in the upper layer of the lamina propria of the mucosa characterise the disorder. PCC is usually refractory to various topical treatments, including corticosteroids [2], antibiotics [3], fusidic acid [3], and antifungal agents [4]. Although cases of PCC successfully treated with topical calcineurin inhibitors [...]

This paper presents an improved method for our recently proposed dynamic displacement measurement based on triangle phase modulation. The use of deep phase modulation eliminates the need for preliminary measurement of half-wave voltage V π for the phase modulator. We demonstrate displacement measurement with tens-of-nanometer scale taking place within a few micro seconds, where the temporal resolution is 33 ns. A long-term stability is also realized by employing a simple feedback control for the interferometer. The measurement precision is proved to be as high as that in the previously developed system that required careful preliminary measurement of V π .

We demonstrate dynamic displacement measurement with phase-modulated light. Auto calibration using deep phase modulation makes the measurement independent of driving conditions of the modulator. Displacement of several tens nm for more-than-1-MHz vibration is successfully measured.

The swallowtail butterfly, Papilio xuthus L., exhibits seasonal diphenism, i.e., spring and summer morphs, the development of which is determined by photoperiod and temperature imposed during the larval stage. Larvae reared under long day conditions at 25°C develop into summer morphs without pupal diapause, while larvae reared under short day conditions at 20°C develop into spring morphs after diapause development at 4°C for more than three months. To investigate the neuroendocrine mechanism regulating seasonal morph development, the activity of the summer-morph-producing hormone (SMPH) was tried to assayed by using male short day pupae of P. xuthus that accomplished diapause development at 4°C. The wing patterns of male butterflies shifted toward summer morphs when short day pupae were treated with the SMPH at an adequate stage. SMPH activity was detected in 2% NaCl extracts of the brain-subesophageal ganglion (Br-SG) complexes of P. xuthus long day pupae. Chilled male short day pupae responded ...

In January 2014, a 34-year-old man was referred to our hospital with hypothermia and mental fog. Clinical examination revealed his legs to be dirty, foul-smelling, red and covered with exudate and accumulated scurf that formed granular brown plaques (figure 1A). Pink nodules were aggregated into cauliflower-like plaques on the ankle joints (figure 1B). The histopathology of a biopsy specimen taken from the dorsal aspect of the ankle joint showed hyperkeratosis, pseudoepitheliomatous hyperplasia, [...]

Oxyfuel combustion is one of the promising technologies to reduce CO2 emission from pulverized coal fired power plant. In order to apply this technology to the commercial boiler, it is important to predict the boiler performance (especially heat recovery characteristics) in Oxyfuel combustion condition. In this study, prediction of heat recovery characteristics of Oxyfuel combustion boiler using CFD was conducted. As a result, it was shown that the same boiler performance can be achieved in Oxyfuel combustion mode as that in Air combustion mode.

The combustion characteristics of coal char particles in either O2/N2 or O2/CO2 conditions were experimentally investigated. Especially, the char burnout, the char particle temperature and the shrinkage of the char particles were discussed. A Drop Tube Furnace (DTF: whose wall temperature was set at 873, 923 and 973 K) was used as the experimental apparatus. The experimental results revealed that, in equivalent oxygen concentration, the char burnout and the char particle temperature were higher in O2/N2 conditions than those in O2/CO2 conditions. The shrinkage of the char particle did not show the large difference in either O2/N2 or O2/CO2 conditions. Up to 15% of char burnout, the char particle diameters were reduced gradually. Up to 80% of char burnout, the char particle diameters were not changed. This is supposed that the chemical reaction is mainly occurred not on the external surface but on the internal surface of the char particle. Over 80% of char burnout, sudden shrinkage could be seen. Finally, an empirical equation for the prediction of the char particle shrinkage was introduced. Further investigation is required in high operating temperature, where CO2 gasification may have a large influence on the char burnout.

Proton Exchange Membrane (PEM) fuel cell systems have been studied as the alternatives of the internal combustion engine systems. However, these systems are not appearing in daily life yet, due to the high cost, shortage of infrastructure, technical issues, etc. Concerning technical issues, water/thermal management is a critical one to keep high proton conductivity in the electrolyte membrane for the design of PEM fuel cell systems. Therefore, the heat and mass balances in the PEM fuel cell system have been studied for a long time. However, the influence of stack design on the power and heat generation have not been deeply discussed yet. In this study, influence of the pressure drop and maldistribution in a PEM fuel cell stack on the heat and mass balance in the 100 kW systems was studied. It has been found the heat load in the radiator is reduced by the consideration of the pressure drop in the stack. This is because of the reduction of the water condensation in the stack. The amount of heat, which is reduced in the radiator, is mostly shifted to the condenser for the water recovery. As a conclusion, it can be argued that, by involving the influence of pressure drop in the stack, the amount of heat load in the radiator is reduced about 5%. This is mostly due to less water condensation in the stack. This reduced heat is shifted to the condenser. It corresponds to about 10% increase in the heat load in the condenser. The design of the radiator and condenser must consider this shift in heat load due to the pressure drop in the stack.

The Proton Exchange Membrane (PEM) fuel cell has been investigated for a long time because it has a high power density, low emission, wide choice of fuel sources, etc. However, the performance of a stack of PEM cells degrades with respect to that of a single cell. This is mainly due to the introduction of the manifold in which supplies the reactants to individual cells. The manifold can induce an additional pressure drop and a flow maldistribution. Therefore, it is critical to consider the interaction between the design of the manifold and the flow maldistribution. In this study, the sensitivity of the friction factor in the individual cells to the flow maldistribution and the interaction between the flow maldistribution and water condensation are discussed. As a result, it is found that the friction factors in the individual cells strongly influences the flow maldistribution especially when the flow in the unit cell is changed from laminar flow to turbulent. Large flow maldistributions induce the large pressure drops. As a result, water condensation can be little. However, it also induces a degradation in stack performance. A bipolar plate with a low number of flow channels can improve the flow maldistribution and water condensation in the unit cell although at the expense of a large pressure drop.

Several serious problems such as material durability and fouling in the High Temperature Heat Exchanger (HTEH) for Externally Fired Micro Gas Turbines (EFMGT) cause the low thermal efficiency. In this study for increasing the thermal efficiency, a duct around a cylindrical fixed bed combustor which burns wood pellets is proposed and two different designs, empty and porous material filled, are investigated. A heat transfer model, based on coupling between radiative and convective modes at the combustor and duct sides is developed to evaluate the important geometrical parameters in the different designs. The predicted results for the empty duct show that although an increase of the combustion length increases the temperature of air at the duct outlet, an increase of the combustor diameter is more effective. In addition, an increase of the duct cross section is the most effective way and according to the predictions, the pressure drop in this case is still acceptable. The porous duct design shows a significant increase in the air temperature at the duct outlet. However, the pressure drop is high. The investigation shows the possibility of reduction of the pressure drop with the same amount of heat transfer by selecting suitable particle size and porosity. Copyright © 2007 by ASME.

Proton exchange membrane fuel cell (PEMFC) systems have been investigated as alternative power sources for the stationary and automotive applications. However, they do not appear on the market yet. One of the main reasons is the difficulty of the water/thermal management in the system. Several water recovery schemes have been proposed to overcome this difficulty and to simplify the system configuration. In this paper, the influence of the water recovery schemes on the water/thermal balances in the PEMFC system is investigated. One is a scheme without water phase change at the condenser and the humidifier. The other is a scheme with water phase change. As a result, at low operating pressure, the scheme with water phase change has a large heat dissipation from the system. This is because large water recovery is required in the condenser. With increasing operating pressure, the influence of the difference in the water recovery scheme is diminished from the thermal balance point of view. This is because the requirement of the water recovery becomes small. In the favorable operating range for the stack, the water/thermal balances in the system with water phase change is quite difficult because the heat loads in the intercooler and condenser are very large. However, the water recovery scheme without phase change can solve this difficulty. This scheme makes the component design simpler in this operating range. Copyright (Less)

In this paper, heat and mass balances of the intercooler in a 100 kW Proton Exchange Membrane Fuel Cell (PEMFC) system are analyzed by employing a commercial software IPSEpro. The compressor, ambient temperature, the humidification method and the PEMFCs cathode operating temperature were considered as the parameters influencing the heat and mass balances in the intercooler. Parametric studies of the heat and mass balances in the intercooler are carried out with various values of the parameters, such as operating pressure, air mass flow rate, compressor efficiency, ambient air temperature, cathode operating temperature and H2O injection temperature for the humidification, etc. As indicated in the paper, in the system with either high ambient temperature, high operating pressure, low cathode operating temperature or internal humidification, the required heat transfer rate in the intercooler is large. However, evaporation of H2O for the humidification contributes to reduction of the required heat transfer rate. Copyright (Less)

In Proton Exchange Membrane Fuel Cell (PEMFC) systems, an intercooler contributes to proper thermal management of the reactant air into the cathode. However, the structure/performance of it is not clear yet. In this paper, two case studies concerning an intercooler in a 100 kW PEMFC system are carried out. Plate-fin and tube-fin heat exchangers are analyzed as the intercooler, in terms of volume, pressure drop and weight, The e-NTU method is used. As general characteristics of the intercooler, the volume is increased with system operating pressure, while the pressure drop is decreased due to the volume expansion. The plate-fin intercooler contributes to the weight reduction of the system because aluminum is used. However, at the high operating pressure, space consumption is large. The tube-fin intercooler contributes to the volume reduction because the coolant is a liquid. However, the usage of stainless steel contributes to weight increase. The tube-fin intercooler in aluminum may contribute to space and weight reduction. However, a liquid coolant, which is proper for the PEMFC stack cooling without corrosion of aluminum, is needed. Copyright © 2005 by ASME. (Less)

Heat exchangers are used in proton exchange membrane fuel cell systems (PEMFCs) for stack cooling, intercooling, water condensation and fuel reforming. Especially, the heat exchanger for the intercooling before the humidifier is investigated in this paper. It is found that, at high pressure or high mass flow rate, the need to cool the air (oxidant) is large. The heat exchanger uses coolant water from the stack cooling system or ambient air as the cold stream. With water-cooling, the volume of the heat exchanger will be small. However, difficulties exist because the small available temperature difference. Air-cooling can be used over a wide operating range but the heat exchanger volume will be large.