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Three-dimensional (3D) printing polymers such as urethane dimethacrylate (UDMA) and ethoxylated bisphenol A dimethacrylate (Bis-EMA) are typically used in definitive prosthesis and require surface treatments before bonding. However, surface treatment and adhesion conditions often affect long-term use. Herein, polymers were divided into Groups 1 and 2 for the UDMA and Bis-EMA components, respectively. The shear bond strength (SBS) between two types of 3D printing resins and resin cements was measured using Rely X Ultimate Cement and Rely X U200, according to adhesion conditions such as single bond universal (SBU) and airborne-particle abrasion (APA) treatments. Thermocycling was performed to evaluate the long-term stability. Sample surface changes were observed using a scanning electron microscope and surface roughness measuring instrument. The effect of interaction between the resin material and adhesion conditions on the SBS was analyzed via a two-way analysis of variance. The optimal adhesion condition for Group 1 was achieved when U200 was used after APA and SBU, whereas Group 2 was not significantly affected by the adhesion conditions. After thermocycling, the SBS significantly decreased in Group 1 without APA treatment and in the entire Group 2. Additionally, porosity, along with increased roughness, was observed on both material surfaces after APA.

This paper examines a historical case where local residents in South Korea had been alienated from the decision-making processes in nuclear policy as their sociotechnical visions remained marginali...

The development of an efficient and stable hole extraction layer (HEL) is crucial for commercializing organic solar cells (OSCs). Although a few candidates have been widely utilized as HELs for OSCs, the most appropriate material has been lacking. A few articles have recently reported graphene oxide (GO) as a well-working HEL that offers comparable performance to conventional HELs. However, a systematic study providing comprehensive insight into the GO-based OSC behavior is lacking. This article discusses broad topics, including the material properties, device efficiency, shelf lifetime, and impedance properties. We found that GO offers excellent properties, which are identical to those of conventional HELs, while the shelf lifetime shows a significant 6-fold increase. Furthermore, we discuss the significantly reduced space-charge limited region of an aged GO-based OSC compared with a PEDOT:PSS-based device, which is revealed to be a reason for the different shelf lifetime. We believe that the results will accelerate the development of GO as an HEL for OSCs and other optoelectronic devices.

The efficiency and operational lifetime of quantum dot (QD) based light-emitting diodes (QLEDs) are essentially affected by the electron–hole charge balance. Although various methods have been reported to improve the charge balance, these methods cause issues at the same time, such as increasing a driving voltage and complicating a device structure. In this work, we introduce hybrid InP/ZnSeS/ZnS QDs, in which the oleic acid ligands are substituted with semiconducting diblock copolymer units possessing hole-transporting carbazole groups, to facilitate hole injection and to reduce electron leakage. As a result, the efficiency and the operational lifetime were improved by 1.4-fold and 4-fold, respectively, with lower driving voltages. Origins of the results were systematically investigated, and we found that the diblock copolymer units surrounding the QDs made the inter-dot distance farther apart from one another, leading to reduced Forster resonance energy transfer between QDs which can cause reduced photoluminescence quantum yields. Also, the hole transporting ability of carbazole groups facilitated hole injection into QDs and blocked excess electron leakage at the same time. The impedance spectroscopy on the devices with the pristine and hybrid QDs before and after bias stress revealed that hole accumulation at the hole transport layer/QD interface significantly affected the operational lifetime of the QLEDs. This work offers a design for the QD emission layer to achieve efficient and stable QLEDs with systematic understanding of the origins.

The binding of the cinnamycin on the biomimetic membrane was studied with respect to time using the surface plasmon resonance(SPR). The membrane was composed of the inner layer tethered on the gold surface and the outer layer formed on the inner layer, which was at the desired ratio of dioleoylphosphatidylethanolamine(DOPE) to dioleoylphosphatidyl- choline(DOPC). On the bilayer, the cinnamycin solution was injected and showed different behavior of the binding with respect to time up on its concentration. For kinetic analysis, the behavior was converted to the coverage fraction with respect to time, which was ratio to the saturated response of 5 μM cinnamycin solution. The fraction change with respect to time was function of the available-site, which was eventually the subtraction of the fraction from one. With the fitting of the first order of the available site, the rate constant was acquired into 6∼7 × 10−3 s-1. Furthermore, the reciprocals of the fraction and the concentration were fitted with the Langmuir adsorption isotherm. From the fitting, the equilibrium constant was between 1 × 107 and 5 × 107 M-1.

Aluminum-ion batteries have many advantages such as the natural abundance of aluminum, high theoretical capacity, and low cost. However, the ionic liquid commonly used as the electrolyte for aluminum-ion batteries has high viscosity, which hinders the migration of charge carriers. In this study, we used various organic solvents as additives for the ionic liquid electrolyte and investigated their effect on the battery performance. The electrolyte containing 45% (v/v) benzene had the best electrochemical properties, which led to a high specific capacity of 90 mA h g-1 at an extremely high current density of 5 A g-1.

The effects of the particle sizes of pulverized coal on the flame structure in a coal fire plant were studied experimentally. This study mainly focused on the inner recirculation zone (IRZ) and exhaust tube vortex (ETV), which are major parameters for a reduction of NOx in swirl-stabilized pulverized coal combustion. To clarify the effects of the coal particle size, three different sized Glencore particles were prepared, namely, under 90 µm (GC90↓), under 150 µm (GC150↓), and between 90 and 150 µm (GC90–150). The temperature of the coal particles, the intensity of the OH chemiluminescence, and the pulverized coal flame structure were compared with the particle sizes of pulverized coal. In a pulverized coal flame, the temperature and OH radical intensity were shown to decrease with an increase in the coal particle size, and the IRZ and ETV increase with a decrease in the particle size. The residence time of the coal particles increase in the IRZ and ETV, which creates a reduction environment and a fuel-rich condition, leading to a reduction of NOx emissions.

This report demonstrates how scanning X-ray fluorescence microscopy (SXFM) and nanoscale X-ray absorption near-edge structure (nano-XANES) can spatially and chemically identify intracellular iron species at the single-cell level, creating an opportunity to examine the role of iron storage in magnetite biomineralization. Fe K-edge nano-XANES measurements of Magnetospirillum gryphiswaldense in varied iron media conditions and iron storage capacity revealed intracellular iron heterogeneities through a distinction between formed magnetosomes and intracellular iron material. This work highlights the potential of nano-XANES in providing an experimental advantage in the multidisciplinary field of biomineralization.

Purpose The aims of the present study were to evaluate the immunogenicity of an inactivated rabies vaccine based on the ERAGS strain. Materials and methods The ERAGS virus propagated in Vero cells was inactivated with 3 mM binary ethylenimine for 8 hours. Three types of inactivated rabies vaccines were prepared to determine the minimum vaccine virus titers. Four further types of inactivated rabies vaccines were prepared by blending inactivated ERAGS with four different adjuvants; each vaccine was injected into mice, guinea pigs, and dogs to identify the optimal adjuvant. The immunogenicity of a Montanide (IMS) gel-adjuvanted vaccine was evaluated in cats, dogs, and cattle. Humoral immune responses were measured via a fluorescent antibody virus neutralization method and a blocking enzyme-linked immunosorbent assay. Results The minimum virus titer of the inactivated rabies vaccine was over 107.0 50% tissue culture infectious doses (TCID50 values)/mL. Of the four kinds of adjuvants, the IMS gel-adjuvanted vaccine induced the highest mean viral neutralizing antibody (VNA) titers of 6.24 and 2.36 IU/mL in guinea pigs and dogs, respectively, and was thus selected as the vaccine for the target animals. Cats, dogs, and cattle inoculated with the IMS gel-adjuvanted vaccine developed protective VNA titers ranging from 3.5 to 1.2 IU/mL at 4 weeks post-inoculation (WPI). Conclusion Our data indicate that cats, dogs, and cattle inoculated with an inactivated rabies vaccine derived from the ERAGS strain developed protective immune responses that were maintained to 12 WPI.

Background Fluorescent antibody virus neutralization (FAVN) test is a standard assay for quantifying rabies virus-neutralizing antibody (VNA) in serum. However, a safer rabies virus (RABV) should be used in the FAVN assay. There is a need for a new method that is economical and time-saving by eliminating the immunostaining step. Objectives We aimed to improve the traditional FAVN method by rescuing and characterizing a new recombinant RABV expressing green fluorescent protein (GFP). Methods A new recombinant RABV expressing GFP designated as ERAGS-GFP was rescued using a reverse genetic system. Immuno-fluorescence assay, peroxidase-linked assay, electron microscopy and reverse transcription polymerase chain reaction were performed to confirm the recombinant ERAGS-GFP virus as a RABV expressing the GFP gene. The safety of ERAGS-GFP was evaluated in 4-week-old mice. The rabies VNA titers were measured and compared with conventional FAVN and FAVN-GFP tests using VERO cells. Results The virus propagated in VERO cells was confirmed as RABV expressing GFP. The ERAGS-GFP showed the highest titer (108.0 TCID50/mL) in VERO cells at 5 days post-inoculation, and GFP expression persisted until passage 30. The body weight of 4-week-old mice inoculated intracranially with ERAGS-GFP continued to increase and the survival rate was 100%. In 62 dog sera, the FAVN-GFP result was significantly correlated with that of conventional FAVN (r = 0.95). Conclusions We constructed ERAGS-GFP, which could replace the challenge virus standard-11 strain used in FAVN test.

The behavior of cinnamycin on a biomimetic membrane was studied with respect to the curvature of a phosphatidylethanolamine (PE)-included membrane with the adhesion measured using an atomic force microscope (AFM). The membrane was formed through vesicle fusion on the hydrophobic surface of silica spheres, which was used to define the curvature of the membrane. The hydrophobicity was generated by the reaction of alkyl-silane and analyzed with an X-ray photoelectron spectrometer. The cinnamycin, immobilized covalently to the AFM tip coated with 1-mercapto-1-undecanol that was observed to be inert to any adhesion to the membrane, showed that the adhesion became stronger with the increase in the curvature. The correlation between the adhesion and the curvature was linearly proportional. Since it was found that the cinnamycin was bound to a PE headgroup and the binding was enhanced by the interaction of the hydrophobic area located at one side of the cinnamycin, the linear proportionality seems to suggest that the interaction is related to the one dimensional orientation of the binding.

Feline panleukopenia virus (FPV) causes fatal leukopenia and severe hemorrhagic diarrhea in cats. Although FPV isolates have been reported worldwide from several animals, the biological and genetic features of South Korean FPVs remain unclear. We characterized molecularly South Korean FPV isolates. Crandell-Rees feline kidney (CRFK) cells were used to isolate FPV from 60 organ homogenates. The isolates were confirmed to be FPVs via analyses of cytopathic effects, immunofluorescence studies, electron microscopy, and polymerase chain reaction. Viral genetic analyses used the full VP2 sequences. Eight isolates propagated in CRFK cells were confirmed to be FPVs. All isolates yielded viral titers ranging from 104.5 to 106.0 TCID50/mL 5 days after inoculation into CRFK cells and exhibited hemagglutination titers ranging from 27 to 212 (using pig erythrocytes). The Korean FPV isolates grew well in cat cells such as CRFK and Fcwf4 cells. The FPV isolates were most similar to the KS42 strain isolated from a Korean cat in 2008. The FPV isolates will serve as useful antigens in future sero-epidemiological studies and will aid in the development of diagnostic tools.

The adductor muscle of the pen shell Atrina pectinata (AMPS) is a popular protein‐enriched food item in Asian Pacific countries, and has only been marketed in the frozen condition, as a result browning and decreased sensory attributes occur. To overcome these problems, superheated steam roasting (at 270°C for 4 min) combined with the hot smoke (10 min) using a selective Oak sawdust was employed to develop a new AMPS product yielding high physicochemical properties during storage periods (0–13 days) especially at 10°C. The processed AMPS showed high sensory preferences because of good odor, color, and textural properties. It also significantly inhibited bacterial growth, volatile basic nitrogen, thiobarbituric acid‐reactive species, and pH changes, and eventually possessed higher nutritional composition with low trimethylamine N‐oxide level. Results indicate that saturated steam allows AMPS at good physicochemical conditions, whereas hot smoke‐derived aroma compounds prolong its shelf life through antioxidant and antimicrobial activities.

The open Hill repair for gastroesophageal reflux disease and hiatal hernia is remarkably durable, with a median 10-year reoperation rate of only 3% and satisfaction of 93%. No long-term data exist for the laparoscopic Hill repair (LHR). Patients who underwent primary LHR at Swedish Medical Center for reflux and/or hiatal hernia at least 5 years earlier (1992–2010) were identified from an IRB-approved database. There were 727 patients who met inclusion criteria, including 648 undergoing repair for reflux and 79 for paraesophageal hernia. Two questionnaires were administered via mail to evaluate long-term quality of life using validated GERD-HRQL, Swallowing score, and global satisfaction score. Outcomes were defined by GERD-HRQL score, Swallowing score, resumption of proton pump inhibitor (PPI) therapy, need for reoperation, and global satisfaction with overall results. Two hundred forty-two patients completed and returned the survey (226 lost to follow-up, 90 deceased, 3 denied undergoing LHR, 166 non-responders), of which 52% were male. The average age at the time of surgery was 49.5 years. Median follow-up was 18.5 years (range 6.2–24.7). The average GERD-HRQL score (7.1) and the average Swallowing score (39.9) both indicated excellent symptomatic outcomes. 30% of patients are using daily PPIs. 24 patients (9.9%) required reoperation for failure during the follow-up period, 21 in the reflux group and 3 in the paraesophageal hernia group. Overall, 85% reported good to excellent results, and 76% would recommend the operation. LHR shows excellent long-term durability and quality of life similar to the open Hill repair, with 85% good to excellent results at a median follow-up of 19 years and a reoperation rate under 10%. It is surmised that Hill suture fixation of the gastroesophageal junction to the preaortic fascia may confer unique structural integrity compared to other repairs.

This paper presents an experimental investigation of the effects of the exhaust tube vortex (ETV) on pollutant emissions and carbon burnout performance. The novelty in this study is to improve understanding of combustion behavior with the ETV structure via detailed in-furnace measurements (temperature, gas-phase species concentration, carbon burnout, emissions, and etc.) in a 16-kWth coal-fired furnace. The experiment considered two different swirling flames (co- and counter-swirl) with four air staging positions. A hollow tubular structure such as the ETV structure has been created under the co-swirl condition. The values of NOx emissions are about 430 ppm, but the CO emission is lower and carbon burnout is approximately 2% higher than that of the counter-swirl unstaging condition at the furnace outlet. For the air staging conditions, the air staging position 3 (SL3) maintained the generated ETV structure stronger in the primary combustion zone. The SL3 condition produced the lowest CO emission at about 275 ppm, and a relatively low emission of NOx showed with the highest carbon burnout performance of approximately 94.5% or more. The SL3 condition is the most favorable condition for the synergistic effect of air staging technology on the ETV structure with a low-NOx swirl-stabilized burner.

The allowable Wobbe index (WI) range proposed by gas turbine companies spans from 0 to 5%. System tuning is required when out-of-range fuel is used. In this study, thermodynamic analysis is conducted to study the gas turbine performance and operability of each component with the fuel exceeding 5% of WI. The novel diluting fuel supply system is employed to apply novel fuel compositions for the J-class gas turbine system. High-hydrocarbon and hydrogen blending fuels are used to study the operability and main parameters of each component. The largest diluent mass flow is required when 100% hydrogen fuel is used with nitrogen diluent method. The compressor cannot be operated with 100% hydrogen fuel due to the compressor surge. The maximum turbine blade temperature with steam diluent methods increases up to 80 °C. The power output and efficiency are enhanced with the increasing blending ratio of high-hydrocarbon and hydrogen employing two diluent methods. When the novel fuel supply system is considered for the stable operability of combustor, both its power and efficiency are increased; however, the operability of compressor and turbine is not always stable, especially with hydrogen fuel.

Numerical analysis of lean-premixed flames is utilized to investigate the correlation between turbulence and combustion, fuel–air mixing, and NO x emission using three types of micro gas turbine combustors. Swirl flows generating vortex breakdown and flow recirculation contributing to mixing uniformity are improved by interaction of burners. Mixing plays an important role in flame dynamics and NO x emission by means of the unmixedness parameter. To discuss the correlation between flame characteristics and vorticity structures, progress variable c is introduced. The flame stability is enhanced by ring-shaped, large-scale vorticity structures, and air–fuel mixing is increased by momentum and kinetic energy.

A numerical evaluation was performed to investigate the effects of swirl arrangement (co-swirling and counter-swirling flows) and coal injection mode (non-, fully-, and partially-premixed with swirling flow) on the flame structure, coal particle uniformity, burnout performance, and nitrogen oxide (NOx) emissions in a 16-kWth coal-fired boiler. The co-swirling flame exhibits a tulip-shaped inner recirculation zone (IRZ), which increases the coal particle residence time: 1.61 s and 1.45 s for co-swirling and counter-swirling flames, respectively. In addition, the high uniformity of coal particles is maintained in all horizontal cross-sections. The total amount of NOx emissions at the boiler outlet are 205.0 and 551.2 ppm (@6% O2) for the co-swirling and counter-swirling flames, respectively; the deNOx efficiency is 62.8%. An exhaust tube vortex (ETV) structure with a tulip-shaped IRZ is observed in the non-premixed swirling flame injection mode; however, the ETV structure is not observed in the other injection modes. The ETV structure enhanced the coal particle uniformity and expanded the reaction zone, consequently reducing the area of the local high-temperature region. Although the non-premixed injection mode has a slightly lower burnout performance than other injection modes, it is determined to be more effective in reducing the total amount of NOx emissions.

In this study, the operating characteristics of a gas turbine combustor are predicted using real-time data from industrial gas turbines. The turbine exhaust temperature (TET) and major gas turbine design parameters are used as input parameters to predict the combustor operation characteristics such as fuel mass flow, turbine inlet temperature, fuel distribution of each nozzle, NOx, operating pressure of combustor, and inlet air temperature of combustor. The sensitivity analysis of input parameters is conducted to optimize predictive neural network structure. The average predicted root mean square error (RMSE) is below 0.02296. Also, for the expandability of the predictive model, 27 turbine exhaust temperature data changes to the mean/median/mean, standard deviation (std)/mid, and std are used as input temperature data. The case that uses the mean TET (TET_mean) shows the highest accuracy. The biggest influence on the prediction error is that when there is a sudden change in operation in a short time, the prediction error becomes large. The peak error occurs at start-up and shutdown process and the nitrogen oxides emission (NOx) has the largest peak RMSE is 0.489. The RMSE from 0.2 to 0.5 occurs just for 20 s at startup and shutdown procedure.

A 16-kWth coal-fired furnace with a dual swirl burner was constructed to investigate the combustion characteristics with/without an exhaust tube vortex (ETV) flame, the combined effect of ETV flame and air staging on pollutant emissions, and the carbon burnout performance. The without ETV flame was more favorable than those of with ETV flames in terms of NO emission. However, its CO emission was primarily higher than those of with ETV flames. Through the correlation between pollutant emissions and carbon burnout, it was confirmed that the case with ETV flame exhibited higher stability than that without ETV flame. Consequently, the ETV flames have a positive effect on carbon burnout performance at every air staging level. In addition, the effects of woody biomass co-firing ratios with ETV flame were evaluated according to pollutant emissions and combustion characteristics, as well as ash deposition using scanning electron microscopy-energy dispersive spectroscopy. The increase in woody biomass co-firing ratio exhibited a positive effect on the NO and unburned carbon reduction. The air-staged combustion was more favorable than the unstaged combustion in terms of NO reduction and ash deposition. Air-staged combustion technology should be applied to reduce ash deposition at the co-firing ratio of 20% or more.

For marine diesel engines, the selective catalytic reduction (SCR) system can be tailored to ensure high nitrogen oxides (NOx) reduction performance, low ammonia (NH3) slip, and low urea consumption. A sufficient mixing zone of urea water solution (UWS) and exhaust gas are required because of the limited installation space. In this study, therefore, mixing units such as a swirl-type mixer and an additional mixing chamber were adopted to improve the flow mixing performance with a low-pressure drop in a marine urea-SCR system. The application of mixing units gave a positive influence on the flow turbulent characteristics and urea decomposition into NH3. The mixer caused flow recirculation and increased turbulent intensity. Moreover, the additional mixing chamber was able to achieve an enhanced residence time for the UWS injections. When mixing units both were combined, it showed the highest conversion efficiency (urea to NH3). In comparison to the SCR system without any mixing units, improvement in the efficiency of deNOx was observed of 61.3 % by the application of the mixing chamber, 76.2 % by the application of the mixer, and 86.3 % by the application of the mixer and the mixing chamber combined.