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The fast pyrolysis of sawdust biomass in the tilted-slide reactor was simulated and the product yields were compared with the experimental results. The biomass was pyrolyzed during it was transferred down to the reactor with the hot sand. The steady-state simulation was performed by a commercial computational fluid dynamics code for predicting the flow, temperature, and concentration of gaseous species together with the particle behaviors. Lagrangian multiphase model was used to simulate the transport of sand and biomass particles, and the kinetic mechanism of biomass pyrolysis was adopted. It was found that the volatile yield continuously increased with temperature due to the absence of the secondary cracking reactions while there is the maximum yield in the experiment. The 1-D calculation considering the secondary gas-phase reactions of the pyrolysis products showed the maximum volatile yield at the temperature about 30∼80˚C higher than the experimental results. At lower temperatures, the volatile yield was much smaller than the benchmark case while the char yield was much larger due to an incomplete conversion of biomass. The fast pyrolysis process in the tilted-slide reactor was investigated along the pyrolyzing particle tracks, and the solid-phase intermediate species were found to be important to evaluate the decomposition of biomass components.

The separated and sorted combustibles from automobile shredder residue (ASR) can be pyrolyzed and used as a heat source or liquefied to produce materials with added value. In this study, the thermal decomposition properties of ASR were determined and thermal kinetic studies were performed. Four types of raw materials were separated from ASR and mixed at a constant ratio: 38.5 wt.% of plastic, 31.6 wt.% of fiber, 17.3 wt.% of sponge, and 12.3 wt.% of rubber. Pyrolysis kinetics analysis was carried out using the Thermogravimetric analysis-derivative thermogravimetry (TGA-DTG) technique and activation energy were calculated by differential and integral isoconversional model methods, Flynn-Wall-Ozawa (FWO), Kissinger-Akahira-Sunose (KAS), and Friedman. Thermogravimetric analysis was performed under nitrogen with four temperature rate conditions from room temperature to 800 &deg, C. In the thermal degradation profile, peaks representing mass loss rates were observed for each sample at different temperature ranges. It was observed that the final mass reduction temperature in the mixed samples was lower than in the individual samples. The activation energies of plastics and rubbers were 105.39 kJ/mol and 115.20 kJ/mol respectively. The sponge foams and fibers were 172.59 kJ/mol and 160.30 kJ/mol respectively. The mixed sample had an activation energy value of 159.56 kJ/mol. The basic physicochemical and pyrolysis characteristics of ASR were examined to be used as basic data for the recycling of ASR for future pyrolysis.

Realization of flexible electronics is an attractive challenge because of its great potential in many applications. However, the design of flexible and highly conductive metal electrodes has been a bottleneck for the fabrication of flexible devices because bulk metals are easily fractured when subjected to elongation or compression. Here, we demonstrate metal-ceramic nanolaminates as electrodes for flexible electronic devices. Insertion of ceramic layers, each with a thickness of a few nanometers, into an otherwise metal electrode significantly improved its strength and bending stability and only slightly reduced its electrical conductivity. Finally, we demonstrated that a touch screen panel fabricated with metal-ceramic nanolaminate electrodes was stable to 200 000 cycles of folding to a bending radius of 3 mm.

Background Nefopam is used to improve postoperative hypothermia in the field of plastic and aesthetic surgery. However, there is a paucity of data about its adverse hemodynamic effects and safety. We therefore assessed its adverse hemodynamic effects in patients undergoing plastic and aesthetic surgery. Methods We conducted a single-center retrospective study of 148 patients, in whom we measured hemodynamic parameters using sphygmomanometry (systolic blood pressure [SBP], diastolic blood pressure [DBP], arterial blood pressure [ABP], and heart rate [HR]). Moreover, we also assessed myocardial oxygen demand using the rate pressure product (RPP). Results The patients included 96 men and 52 women, with a mean age of 34.7±8.5 years. There were no significant differences in SBP, DBP, ABP, HR, or RPP before and after nefopam administration (P>0.05). However, a significant difference was found in the number of the patients with an HR of >100 beats per minute or with an RPP of >12 U before and after nefopam administration (P=0.001). Conclusions Surgeons should consider the possibility of tachycardia and increased blood pressure in the management of postoperative hypothermia in patients with cardiac arrhythmia, ischemic heart disease, or essential hypertension. Nonetheless, further prospective, large-scale, multi-center, randomized, controlled studies are warranted to confirm our results.

Background We conducted this study to identify factors that may prolong the length of the hospital stay (LHS) in patients with diabetic foot (DF) in a single-institution setting. Methods In this single-center retrospective study, we evaluated a total of 164 patients with DF, and conducted an intergroup comparison of their baseline demographic and clinical characteristics, including sex, age, duration of diabetes, smoking status, body mass index, underlying comorbidities (e.g., hypertension or diabetic nephropathy), wound characteristics,type of surgery, the total medical cost, white blood cell (WBC) count, C-reactive protein (CRP) levels, erythrocyte sedimentation rate, and albumin, protein, glycated hemoglobin, and 7-day mean blood glucose (BG) levels. Results Pearson correlation analysis showed that an LHS of >5 weeks had a significant positive correlation with the severity of the wound (r=0.647), WBC count (r=0.571), CRP levels (r=0.390), DN (r=0.020), and 7-day mean BG levels (r=0.120) (P5 weeks had a significant positive correlation with the severity of the wound (odds ratio [OR]=3.297; 95% confidence interval [CI], 1.324–10.483; P=0.020), WBC count (OR=1.423; 95% CI, 0.046–0.356; P=0.000), CRP levels (OR=1.079; 95% CI, 1.015–1.147; P=0.014), albumin levels (OR=0.263; 95% CI, 0.113–3.673; P=0.007), and 7-day mean BG levels (OR=1.018; 95% CI, 1.001–1.035; P=0.020). Conclusions Surgeons should consider the factors associated with a prolonged LHS in the early management of patients with DF. Moreover, this should also be accompanied by a multidisciplinary approach to reducing the LHS.

Turbo-expanders have been used for energy conversion in many fields. They are sometimes operated in partial admission mode, depending on the stability of the energy source, such as solar energy or waste thermal energy, which can fluctuate depending on environmental or process condition. The ability to operate in partial admission can be advantageous because it allows continuous operation without interchanging components. However, this method also leads to lower turbo-expander efficiency. This experimental study was conducted to investigate losses at various partial admission rates. In addition, the effect of tip clearance was studied since it is another important parameter affecting turbo-expander performance. A linear cascade was fabricated with a nozzle that was set to 65° based on the axial direction. A blade row was designed to be movable along the pitchwise direction in order to investigate flow characteristics as a function of blade movement. Flow structures and pressure losses were measured for various partial admission rates and tip clearances. The experiment was conducted at a Reynolds number of 3 × 105 based on the chord. The experimental results showed that losses in the passages depended not only on partial admission rate but also location relative to the nozzle.

An environment-friendly treatment of organic waste like swine manure and food waste is considered to be big challenge, because the residue of organic wastes after anaerobic digestion contains still high amount of undigested organics and is not allowed to dump to ocean by international regulation. The residue from anaerobic digestion of organic wastes, on the other side, has high energy potential because of its leftover organics. In this study a new and integrated treatment process plant of 40 ton swine manure with 20 ton food waste a day has been developed to achieve environment-friendly disposal of swine manure and to produce renewable solid fuel, which has combined two processes of biogas plant and bio solid-refuse-fuel plant. The residue of anaerobic digestion from biogas plant was conveyed to the bio solid-refuse-fuel plant and dried in dryer using the biogas produced in biogas plant as a burner fuel and finally pelletized for a renewable solid fuel. About 30% of total biogas was supplied for 8 h operation of dryer and the leftover 70% was used for generating electricity in the 250 kW gas engine power generator. The produced pellet was analyzed to have good fuel property that meets the Korea Bio Solid-Refuse-Fuel Quality Standard.

Coffee-grounds (CFs) are simultaneously pyrolyzed with waste polystyrene foam (PS) in a bubbling fluidized bed reactor according to the following conditions: a temperature of 500 °C selected from the thermogravimetric analyses of CFs and PS, the nitrogen flow rate of about 20–25 L/min., and the feeding rate of 200 g/h. Multiple CFs/PS mixing ratios were treated as follows: 75:25, 50:50, 25:75. The properties, the chemical compositions of the co-pyrolysis oils and the yields of the products were compared with those of the pyrolysis-oils of the individual feedstocks to demonstrate the synergy between the CFs and the PS. The synergy with the co-pyrolysis produced a higher liquid yield than the calculated amount. The higher heating value of co-pyrolysis oils increased to 39.66 MJ/kg, which was equivalent to that of conventional fuels. Blending at least 25% of PS to CFs could greatly reduce the viscosity of CFs pyrolysis oil (from 724.65cP to 29.3cP at 24 °C). Chemical distributions have shown that the synergy effect between CFs and PS has drastically enhanced the production of hydrocarbons, especially in aromatic compounds.

Biocrude-oil, produced through thermochemical process of fast pyrolysis, can also be a possible alternative renewable liquid fuel, although lower in heating value in comparison to that of conventional petroleum fuels. Aqueous biocrude-oil solutions can be a favorable intermediate step in the production of hydrogen. Annually abundantly found Ceylon Refused Tea Waste is used in this study to produce biocrude-oil, while producing a sustainable and useful biochar. Ceylon Refused Tea was subjected to varying pyrolysis reaction temperatures ranging from 723, 773, 823 and 873 K in order to analyze the variations of physico-chemical properties of produced biocrude-oils alongside establishing optimum mass and energy yields for biocrude-oil production. Thermogravimetric and kinetic analysis was also performed for Ceylon Refuse Tea Waste. The reaction temperature of 773 K converted the highest biocrude-oil energy yields with a HHV of 15.6 MJ/kg and a water content of 36.8 wt%. The FTIR analysis establishes high aqueous fractions of biocrude-oil which can lead to favorable hydrogen production. Comparative study is done with respect to Douglas fir and coffee ground on the suitability of the feed in producing biocrude-oil.

Autoignition characteristics of laminar nonpremixed methane jet flames in high-temperature coflow air are studied numerically. Several flame configurations are investigated by varying the initial temperature and fuel mole fraction. At a relatively low initial temperature, a non-autoignited nozzle-attached flame is simulated at relatively low jet velocity. When the initial temperature is higher than that required for autoignition, two regimes are investigated: an autoignited lifted flame with tribrachial edge structure and an autoignited lifted flame with Mild combustion. The autoignited lifted flame with tribrachial edge exhibited three branches: lean and rich premixed flame wings and a trailing diffusion flame. Characteristics of kinetic structure for autoignited lifted flames are discussed based on the kinetic structures of homogeneous autoignition and flame propagation of stoichiometric mixture. Results showed that a transition from autoignition to flame propagation modes occurs for reasonably stoichiometric mixtures. The autoignited lifted flame with Mild combustion occurs when methane fuel is highly diluted with nitrogen. The kinetic structure analysis shows that the characteristics of Mild combustion can be treated as an autoignited lean premixed lifted flame. Transition behavior from Mild combustion to nozzle-attached flame was investigated by increasing the fuel mole fraction. As the maximum flame temperature increases with decreasing liftoff height, the kinetic structure showed a transition behavior from autoignition to flame propagation of a lean premixed flame.

In the present study, the impacts of hydrogen addition on micro and nanostructures of soot particles were evaluated in an ethylene-air counter diffusion flame configuration. To quantitatively interpret the impacts of hydrogen addition to the counter diffusion flame, the hydrogen was added in the fuel stream and its content (in volume %) was gradually increased up to 25%. Soot particles formed within hydrogen added flames were then sampled and imaged using a high resolution transmission electron microscopy (HRTEM) to visualize their micro and nanostructures. In addition, a series of numerical investigations were also performed to build a bridge between molecular gas phase species and the soot micro and nanostructures. Adding the hydrogen to the fuel stream was found to decrease the size of soot microstructures and enhance the formation of fullerenic nanostructures defined as highly curved carbon lamella. The abundance of hydrogen in the flames deactivated the surface site of soot particles, leading to reductions in the size of soot microstructures. Also the hydrogen addition was found to be related to the increased formation of PAHs containing 5-membered rings that helps to develop the curvatures in the carbon lamella.

A burner system with capacity of 30,000 kcal/h was designed for the combustion of biocrude-oil and ethanol blends. An air atomizing spray nozzle with larger fuel orifice was adopted to prevent nozzle clogging, with swirl flow introduced to the combustion air for flame stabilization. Biocrude-oil was prepared from the fast pyrolysis of woody biomass and was blended with ethanol to improve flame stability and ignition characteristics. At various mixing ratios of biocrude-oil and ethanol, flame stability was determined, and gaseous emissions of CO and NO were measured. It was found that stable combustion could be achieved with up to 90 vol% of biocrude-oil. CO emissions of biocrude-oil/ethanol blends were smaller than those of pure ethanol, whereas CO concentration increased significantly in case of pure biocrude-oil due to incomplete combustion. Pollutant NO emission increased slightly with the biocrude-oil mixing ratio. The biocrude-oil burner in this study could provide a design database for industrial burner development.

Biocrude-oil characteristics were investigated from fast pyrolysis of a mixture of Douglas fir and coffee ground. The mixture was prepared on a 1: 1 weight basis and pyrolyzed in a bubbling fluidized bed reactor. Characteristics of biocrude-oil were compared at various reaction temperatures ranging from 673-873K. The mixture resulted in a more improved quality biocrude-oil than each biomass feedstock at the reaction temperature of 823 K with significantly low atomic ratio of 0.43 O/C. The kinetic parameters for biomass decomposition were investigated through Friedman, KAS, FWO and CC isoconversional models. In mixture pyrolytic conversion range of 0.1-0.8, the average activation energy was found to be 135 kJ/mol. The results showed that pyrolysis of coffee ground with Douglas fir has more synergetic effect than individual biomass, which leads to a potentially higher quality fuel with lower activation energy to that of biomass.

Anisakis is a parasite with life cycles involving fish and marine mammals. Human infection, anisakiasis, occurs with the ingestion of raw infected seafood and usually presents with acute or chronic gastrointestinal symptoms from esophageal or gastric invasion. We report a rare caseinvolving the oral cavity. A 39-year-old male presented with oral and sub-sternal pain of one day duration after eating raw cuttlefish. Physical examination revealed areas of erythema and edema with a central white foreign particle on the labial and buccal mucosa. With microscopic field we could remove the foreign material from the lesions. The foreign material was confirmed to be Anisakis. Anisakis was also removed from the esophagus by esophagogastroduodenoscopy. The patient was discharged the following day without complication. Anisakiasis is frequently reported in Korea and Japan, countries where raw seafood ingestion is popular. The symptoms of acute anisakiasis include pain, nausea, and vomiting and usually begin 2-12 hours after ingestion. The differential diagnosis includes food poisoning, acute gastritis, and acute pancreatitis. A history of raw seafood ingestion is important to the diagnosis of anisakiasis. Treatment is complete removal of the Anisakis to relieve acute symptoms and prevent chronic granulomatous inflammation.

Penile verrucous carcinoma is known for its favorable biologic behavior and lack of metastatic potential. For preservation of function, treatment has been focused on partial penectomy. Despite partial penectomy for preservation of minimal functional and aesthetic aspects, patients have experienced psychosexual problems. A 73-year-old man had a cauliflower-like verrucous carcinoma on the penile glans and coronary sulcus diagnosed by using excisional biopsy. He underwent degloving excision to save the penile shaft and glans penis. Surgical margin was 3 mm. He had been tumor-free at the 2-year follow-up. For maximum preservation of the functional and aesthetic aspects, we recommend degloving excision.

Coffee ground has been recently considered as a new biomass resource in relation to the increasing coffee consumption worldwide. The bio-crude oil can be produced by fast pyrolysis of coffee ground, and it has advantages of larger heating values in comparison with those from other biomass. But the bio-crude oil from coffee ground has a significantly high viscosity which can hinder the application to conventional burners. In this study, a pilot-scale burner system with a 35 kW capacity with an air-blast atomizing nozzle was developed for the combustion of bio-crude oil from coffee ground with a high viscosity. A downward fuel injection system was adopted to enhance the ignition of fuel spray and the flame stabilization, and a movable block swirl generator was installed for the combustion air. The bio-crude oil was blended with ethanol at the volumetric ratio of 9:1 to enhance the combustion characteristics. The effect of various atomizing air pressures, swirl intensities, and overall equivalence ratios on the flame stability and gaseous emission were investigated to find out the optimum operating conditions for a bio-crude oil burner.

Conversion technology of solid biomass to liquid fuel, named bio-crude oil, has been researched widely for the production of renewable energy to replace fossil fuel oil. As the result of many admirable researches, fast pyrolysis technology for bio-crude oil production is close to commercialization. However, bio-crude oil has unsatisfactory properties compared to general petroleum oil, for instance, low heating value, high water content, and high viscosity. In this study, pine sawdust (SD) biomass was co-pyrolyzed with waste polystyrene foam (WPSF), which was expected to improve the bio-crude oil quality due to high heating value and non-oxygen composition of polystyrene. The co-pyrolysis experiment was conducted in a bubbling fluidized bed reactor under the following conditions: temperature of 500 °C which was chosen based on the results from thermogravimetric analysis of SD and WPSF, nitrogen flow rate of 20–25 L/min., and feeding rate of 200 g/hr. Various mixing ratios of SD/WPSF by weight percentage were tested as follows: 100/0, 95/5, 90/10, 85/15, 80/20, 75/25, 70/30, 60/40, 50/50, 25/75, 0/100. Experimental results showed that in case of only SD feeding the bio-crude oil yield and higher heating value (HHV) were 48.83 wt% and 17.81 MJ/kg respectively. By contrast, oil yield and HHV in case of 25% SD with 75% WPSF mixture were 63.31 wt% and 39.65 MJ/kg respectively. Additional analysis showed that water content, and acetic acid concentration of bio-crude oil from co-pyrolysis of SD/WPSF mixture were decreased almost proportionally with the increasing WPSF ratio. Furthermore, measured values of water content, and acetic acid concentration were lower than the calculated values by linear interpolation, which means that the synergistic effect between SD and WPSF was achieved during the co-pyrolysis. In conclusion, co-pyrolysis of SD and WPSF was found as a promising solution to improve bio-crude oil quality. With this technology, the industrial growth of bio-crude oil area is expected as well as waste plastic.

In order to augment the performance of vertical axis wind turbines, wind power towers have been used because they increase the frontal area. Typically, the wind power tower is installed as a circular column around a vertical axis wind turbine because the vertical axis wind turbine should be operated in an omnidirectional wind. As a result, the performance of the vertical axis wind turbine depends on the design parameters of the wind power tower. An experimental study was conducted in a wind tunnel to investigate the optimal design parameters of the wind power tower. Three different sizes of guide walls were applied to test with various wind power tower design parameters. The tested vertical axis wind turbine consisted of three blades of the NACA0018 profile and its solidity was 0.5. In order to simulate the operation in omnidirectional winds, the wind power tower was fabricated to be rotated. The performance of the vertical axis wind turbine was severely varied depending on the azimuthal location of the wind power tower. Comparison of the performance of the vertical axis wind turbine was performed based on the power coefficient obtained by averaging for the one periodic azimuth angle. The optimal design parameters were estimated using the results obtained under equal experimental conditions. When the non-dimensional inner gap was 0.3, the performance of the vertical axis wind turbine was better than any other gaps.

The stabilization characteristics of laminar non-premixed jet flames of pre-vaporized iso -octane, one of the primary reference fuels for octane rating, have been studied experimentally in heated coflow air. Non-autoignited and autoignited lifted flames were analyzed. With the coflow air at relatively low initial temperatures below 940 K, an external ignition source was required to stabilize the flame. These lifted flames had tribrachial edge structures and their liftoff heights correlated well with the jet velocity scaled by stoichiometric laminar burning velocity, indicating the importance of the edge propagation speed on flame stabilization. At high initial temperatures over 940 K, the autoignited flames were stabilized without requiring an external ignition source. These autoignited lifted flames exhibited either tribrachial edge structures or mild combustion behaviors depending on the level of fuel dilution. Two distinct transition behaviors were observed in the autoignition regime from a nozzle-attached flame to a lifted tribrachial-edge flame and then to lifted mild combustion as the jet velocity increased at a certain fuel dilution level. The liftoff data of the autoignited flames with tribrachial edges were analyzed based on calculated ignition delay times. Analysis of the experimental data suggested that ignition delay time may be much less sensitive to initial temperature under atmospheric pressure conditions as compared with predictions.

Hastelloy X in this study was applied in jet engine F-15 air fighter as shroud to isolate the engine from outer skin. After 15 years operation at elevated temperature the mechanical properties decreased gradually due to the precipitation of continues second phases in the grain boundaries and precipitated inside the grain. The crack happened at the edge of the shroud due to the thermal and mechanical stress from jet engine. Selective TEM analysis found that the grain boundaries consist of M23C6 carbide, M6 Ccarbide and small percentage of sigma(σ) phase. Furthermore, it was confirmed the nano size of σ and miu (μ) phase inside the grain. In this study, it was investigated the microstructure of the degraded shroud component and HAZ of repair welded shroud. In the HAZ, it was observed the dissolution of the M23C6 carbides and smaller precipitates, the migration of the undissolved larger M23C6 carbide and M6 Ccarbide. It is also observed the liquation due to the simply melt of the segregated precipitates in the grain boundaries. Interestingly, the segregated second phases which simply melt in the grain boundaries more easily happened at higher heat input welding condition. High temperature tensile test was done at 300ﾟC,700ﾟC and 900ﾟC. It was obtained that the toughness of welded sample is lower compare to the non-welded sample. The solution heat treatment at 1170ﾟC for 5 minutes was suggested to obtain a better mechanical properties of the shroud. The high cycle fatigue number of the repair welded shroud shows a much lower compare to the shroud. In addition, the high cycle fatigue number at room temperature after solution heat treatment was almost double compare to the before solution heat treatment under 420-500MPa stress amplitude. However, the high cycle fatigue number of repaired welded sample was shown a much lower compare to the non- welded shroud and solution treated shroud. One of the main reasons to decrease the tensile strength and the high cycle fatigue properties of the repair welded shroud is the formation of the liquid phase in HAZ.

The ORC (organic Rankine cycle) has been used to generate electrical or mechanical power from low-grade thermal energy. However, even though many kinds of such energy are available, this thermal energy is typically not available continuously at a constant level. In order to utilize fluctuating thermal energy optimally, an axial-type turbine was applied to the expander, and two nozzles were used to control the mass flow rate. The tip diameter of the rotor was 80 mm and the nozzle was designed as a supersonic nozzle to increase the turbine output power. Experiments were conducted at various TIT (turbine inlet temperatures) with the partial admission rate of 16.7%. The experimental results were compared with the predicted results of the cycle analysis. In the cycle analysis, the output power of the ORC was predicted considering the load dissipating the output power produced by the ORC, as well as the turbine efficiency. The predicted results showed the same trend as the experimental results, and the experimental results showed that the system efficiency of 2% was obtained at the TIT of 100 °C. Hence, this type of turbine can be applied to produce a wide range of power continuously where the available thermal energy varies.