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The effect of distributor geometry on bubble characteristics in an air–kerosene system of a pressurized bubble column was evaluated. The experiment was carried out using a cylindrical stainless column with an inner diameter of 0.097 m and a height of 1.8 m under a system pressure up to 3.5 MPa. The gas holdup was calculated under pressure taps from 0.05 m to 0.85 m above the distributor along axial direction of the column. Bubble size was measured with an optical probe installed 0.5 m above the distributor. Perforated plates with four different hole sizes including 0.8 mm (20 each), 1 mm (12 each), 2 mm (3 each), and 3.46 mm (1 each) fixed with the same opening fraction (ϕo = 0.128%) were evaluated. Different opening fractions at 0.223% (21 holes), 0.128% (12 holes), 0.074% (7 holes), and 0.032% (3 holes) were also tested with a constant hole size (1 mm). The effect of the distributor geometry on bubble characteristics was determined with seven different types of perforated plates. The number of microbubbles was increased with decreasing opening fraction of the distributor. Based on dynamic gas disengagement (DGD) analysis, microbubbles were rarely generated in all distributors under conditions of Psys = 0.1 MPa at Ug = 12.3 mm/s. However, a significant number of microbubbles were generated at ϕo = 0.032% despite a low flow rate at Psys = 3.5 MPa. Microbubble ratio varied from 36% to 40% at ϕo = 0.128 %, while this ratio varied from 38% to 73% at ϕo = 0.032%.

The effect of particle size distribution on the hydrodynamics of dilute-phase pneumatic conveying system was analyzed using computational particle fluid dynamics (CPFD) simulation. The influence of a simulation parameter, i.e., correction factor of drag coefficient (k), on the hydrodynamics of pneumatic conveying system was determined via CPFD simulation. When results of simulation were compared with experimental data of previous studies, the average error of pressure drop per length predicted by the CPFD approach with the correction factor was below 4.4%. Saltation velocity and the pressure drop per unit length declined as the drag force coefficient increased. Simulation results also revealed that the pressure drop per length and the saltation velocity were decreased when the fine powder fraction in the particle size distribution was increased, although the width of particle size distribution was widened, and the standard deviation was increased. Finally, the Relative Standard Deviation (RSD) of pressure drop per length was measured and compared with median diameter (d50), Sauter mean diameter, geometric mean diameter, and arithmetic mean diameter. The RSD of the Sauter mean diameter was 5.8%, approximately twice less than the RSD value of d50 commonly used in pneumatic conveying.

This paper proposes a simplified elastic-plastic analysis procedure using the penalty factors presented in the Code Case N-779 for strain-based fatigue assessment of nuclear safety class 1 components under severe seismic loads such as safety shutdown earthquake and beyond design-basis earthquake. First, a simplified elastic-plastic analysis procedure for strain-based fatigue assessment of nuclear safety class 1 components under the severe seismic loads was proposed based on the analysis result for the simplified elastic-plastic analysis procedure in the Code Case N-779 and the stress categories corresponding to normal operation and seismic loads. Second, total strain amplitude was calculated directly by performing finite element cyclic elastic-plastic seismic analysis for a hot leg nozzle in pressurizer surge line subject to combined loading including deadweight, pressure, seismic inertia load, and seismic anchor motion, as well as was derived indirectly by applying the proposed analysis procedure to the finite element elastic stress analysis result for each load. Third, strain-based fatigue assessment was implemented by applying the strain-based fatigue acceptance criteria in the ASME B&PV Code, Sec. III, Subsec. NB, Article NB-3200 and by using the total strain amplitude values calculated. Last, the total strain amplitude and the fatigue assessment result corresponding to the simplified elastic-plastic analysis were compared with those using the finite element elastic-plastic seismic analysis results. As a result of the comparison, it was identified that the proposed analysis procedure can derive reasonable and conservative results.

Comprehensive air monitoring of hazardous air pollutants (HAPs) was conducted at four residential sites (three in the town and one in a suburb) in Pohang, where Korea's largest iron-steel industrial complex is located. The objectives of this study were to evaluate the occurrence and spatiotemporal distributions of HAPs and to identify important HAPs based on a health risk assessment. The 130 HAPs that were measured simultaneously included volatile organic compounds (VOCs), carbonyls, polycyclic aromatic hydrocarbons (PAHs), phthalates, and heavy metals (HMs). The impact of industrial emissions on the ambient levels of HAPs in Pohang appeared to be significant, because the concentrations of multiple HAPs at residential sites near the industrial complex were considerably higher than those at the suburban site. The concentrations of VOCs (except formaldehyde) and HMs did not exhibit a specific seasonal pattern, but PAH levels were generally 4–5 times higher in winter than in summer. The cumulative cancer risks posed by 28 HAPs averaged over the three residential sites and the suburban site were 2.3 × 10−4 and 1.6 × 10−4, respectively, both of which exceeded the tolerable risk criterion of 1 × 10−4. Benzo[a]pyrene posed the highest risk, followed by As, formaldehyde, benzene, and dibenz[a,h]pyrene. However, no single HAP exceeded the non-cancer risk criterion of 1. These results support the need for stricter controls on emissions of PAHs, VOCs, and HMs in Pohang, particularly for sources in the iron-steel industrial complex.

Due to their target specificity and low-toxicity, insect growth regulators (IGRs) are regarded as promising alternatives to chemical insecticides. In this study, farnesol and farnesyl acetate exhibited juvenile hormone (JH)-based IGR activities. While farnesyl acetate showed JH agonist (JHA) activity in concentration-dependent manner, farnesol was identified as JH antagonist (JHAN) by interfering pyriproxyfen-mediated binding JH receptor complex. Both compounds showed mosquito larvicidal activities and caused retardation of ovarian growth of female Aedes albopictus by modulating the formation of JH receptor complex, expression of JH-inducible genes, and thereby disrupting JH-based endocrine regulations. These results suggested that farnesol and farnesyl acetate could be applicable for investigating underlying mechanisms of JH-regulated insect physiologies as well as developing novel eco-friendly insecticides.

This paper investigates the equilibrium performance of CaO hydration and CaCO3/Ca(OH)2 co-calcination in calcium-looping processes. A novel lime hydration configuration is proposed, introducing saturated steam as the reactivating reagent and direct-heat-removal medium. The proposed hydrator generates a substantial amount of superheated steam, used elsewhere as required. The slaked lime and limestone are calcined simultaneously in a methane-concentrated oxy-fuel calciner. The equilibrium performance of the co-calciner is studied at different reactor temperatures, operating pressures, solid/gas feed ratios and feed compositions. A correlation is proposed which estimates the required gaseous feed composition for autothermal, coke-free and complete sorbent regeneration using this novel technology.

The generation of fines by attrition in fluidized bed reactors can cause problems. Thus, the objective of this study was to examine the amount of fines generated in the cyclone not only by attrition, but also by detachment of fine attached to surface according to time. Using a circulating fluidized bed (0.076 m ID × 3.7 m height), variables including cyclone inlet velocity (20.6–30.9 m/s), solid loading ratio (0.5–1 kg-solid/kg-air), and elapsed time (0.5–13 h) were investigated. The fine generation ratio was analyzed by dividing it into two components: the surface particle detachment ratio and the attrition ratio. The surface particle detachment ratio decreased rapidly with increasing cyclone inlet velocity and solid loading ratio. The attrition ratio was positively affected by the cyclone inlet velocity but negatively affected by the solid loading ratio, as found in previous studies. As the surface particle detachment ratio decreased with elapsed time, its contribution to the amount of fine particles generated decreased over time (73%–91% at 0.5 h and 41% at 5 h). The mass fraction produced by surface particle detachment was approximately 9% for the iron ore and 0.01% for catalyst particles.

Biomass gasification is one of the primary thermal conversion processes where fluidized bed reactors are often used to produce syngas with low heating values. However, there has not yet been an effective model to predict gasification yield with broad applicability. In this study, machine learning was adopted to realize the prediction of syngas compositions and lower heating values (LHV) using various lignocellulosic biomass feedstocks at a wide range of operating conditions. Three machine learning techniques, i.e., Random Forest (RF), Support Vector Machine (SVM) and Artificial Neural Network (ANN) were adopted after determining hyperparameters optimization. Pearson correlation and permutation importance were used for the sensitivity analysis. RF and ANN were found to have high prediction accuracy with R2 and RMSE results (RF: R2=0.809-0.946, RMSE=1.39-11.54%; ANN: R2=0.565-0.924, RMSE=1.46-10.56%). Monte Carlo filtering (MCF) was integrated into the three machine learning algorithms to forecast the desired products by predicting the important features of the operating conditions and biomass characteristics. Considering the desired H2/CO > 1.1 and LHV > 5.86 MJ/m3, the RF-MCF was a more suitable approach with R2=0.791-0.902 for H2, CO and LHV features. The machine learning approach can be widely adapted in various scenarios predicting output features as well as MCF for finding the significant variables for optimization.

Unilateral condylar hyperplasia (UCH) of the mandible is a disorder affecting the condyle size, resulting in facial asymmetry. This study was a retrospective review of 27 patients with UCH who underwent condylectomy between 2000 and 2017 at Yonsei University Dental Hospital. Patient demographic characteristics were summarized. UCH was divided into three subtypes: hemimandibular elongation (HE, n=15), hemimandibular hyperplasia (HH, n=4), and osteochondroma (OC, n=8). Of the 27 patients, only one with the HE type and five (18.5%) with the OC type complained of joint pain. Bone scans of all patients showed higher uptake on the UCH side. Lip and maxillary canting was prominent in the HH and HE types. Five patients (18.5%) underwent condylectomy alone, 13 (48.1%) underwent condylectomy with orthodontic treatment, and nine (33.3%) underwent adjunctive jaw surgery with orthodontic treatment. The treatment modalities varied according to the subtype. In all OC type patients, removal of the hyperplastic condyle treated the facial asymmetry. Additional post-surgical orthodontic treatment was necessary in only three cases (37.5%). All HH type patients required mandibuloplasty. All patients showed a stable occlusal outcome without relapse and an improvement in subjective symptoms, despite a decrease in mouth opening of 2.2mm. These findings might be useful in treatment planning for UCH patients.

The Internet of Things (IoT) is an emerging paradigm, where the ubiquitous devices can form the networks and connect to Internet. Security and management of devices remain open challenges for the IoT. We adopt the management framework of industry consortium THREAD, where a group of devices cooperating to accomplish the same task (called policy) are administrated by a designated device called commissioner and together they form a policy group. All these policy groups are further managed by a centralized server. In this hierarchical network structure, the secure distribution of the policy information, access control, and group key from the centralized server to commissioner and its peers become challenging given the pervasive, complex and heterogeneous properties of devices. To solve this, we propose protocols/mechanisms along with a variant of Broadcast Encryption called Secure Identity-Based Broadcast Encryption (SIBBE) and demonstrate the feasibility for secure distribution of information to the IoT devices from centralized server. Most of the related work is based on the Attribute-based Encryption (ABE) for IoT devices, which has scalability issues with the number of attributes. Our experimental and simulation evaluations show that our scheme outperforms the existing schemes in terms of scalability, latency, and communication overhead.

The attrition of binary mixtures of iron powder, as a representative oxygen carrier, and limestone, as a CO2 sorbent, was investigated to examine the interactions of two different solid species. An air-jet apparatus based on ASTM D5757, with several improvements, was used to test particle attrition for various times (3, 6 and 12 h), temperatures (20, 250 and 500 °C), gas flow rates (6, 8 and 10 LPM) and particle mixture compositions (Iron:Limestone mass ratios 1:0, 0.75:0.25, 0.5:0.5, 0.25:0.75 and 0:1). Attrition was affected by the fluidization velocity in relation to the minimum fluidization velocities of the two species, and the mixture mass ratio. High temperature increased the generation of iron fines, while reducing the production of limestone fines. As expected, increasing the air flow rate led to the generation of more fines of both iron and limestone.

This study is focused on the synthesis of bone char (BC) and its application in adsorptive removal of fluoride from the water. The BC was synthesized by the thermal pyrolysis of used cattle bones. In preliminary stage, BC was synthesized at different temperatures ranging from 350 to 700 °C and due to the higher surface area and adsorption capacity, BC synthesized at 350 °C was selected for further experiments. The XRD pattern of BC found better in agreement with the standard pattern of hydroxyapatite. FTIR analysis also signified basic spectra of hydroxyapatite with specific bands at wavelength of 3429, 1639, 1453, 1037, 604 and 566 cm−1. Typical agglomerated structure of hydroxyapatite was witnessed in morphological examination with SEM. The specific surface area, total pore volume and the average pore diameter were found 79.34 m2 g−1, 0.041 cm3 g−1 and 2.09 nm, respectively. The elemental chemical analysis revealed 1.71 Ca/P ratio. About 10.56 mg of fluoride was adsorbed on 1 g of BC. The adsorption isotherm data was briefly illustrated by applying Langmuir isotherm model and Freundlich isotherm model. In conclusion, BC is successfully synthesized and the highest fluoride adsorption capacity was achieved as compared with earlier studies.

Distorted Heusler compound of D019 Mn3Ge polycrystalline films were studied in terms of their crystalline structures and antiferromagnetic behavior by varying annealing temperature and Mn-Ge composition. Although low temperature growth for 30 nm Mn3Ge showed no diffraction peaks in X-ray diffraction patterns, high temperature growth over 773 K with Mn-rich composition is found to promote the (0001) orientation of D019 Mn3Ge which resulted in the emergence of an exchange bias effect in Co0.6Fe0.4 ferromagnetic layer at 120 K. The exchange bias field of 12 Oe in Mn3.16Ge film grown at 773 K were improved to 61 Oe by enriching Mn composition to Mn3.97Ge. The average blocking temperature was measured to be at 150 K which is not as high as its reported Neel temperature of 390 K in the bulk state, however, further improvements are expected by doping additional transition elements.

Vertically aligned and dense InGaAs nanowires were grown on Si (111) substrates by Au-assisted molecular beam epitaxy, and their antireflection characteristics were studied. The bandgap of InGaAs nanowires was tuned to be about 1.0 eV by adjusting the In to Ga ratio. The grown nanowires were vertically aligned with a diameter of ~ 20 nm near the top and ~ 44 nm at the bottom, with a slightly tapered structure. This tapered nanostructure was formed due to the different surface diffusivities and affinities of In and Ga to the Au catalyst. The grown InGaAs nanowires have no significant stacking, kinking, and bending defects. High-resolution transmission electron microscopy study showed that the grown InGaAs nanowires have a pure wurtzite single crystalline structure with the maximum length of ~ 18 µm. Photo-reflectometry measurement showed a significant reduction in the reflectance less than ~ 5% at normal incidence in the wavelength range of 200–1700 nm. In addition, spectroscopic ellipsometry study showed a reduced reflectance at various incident angles of 30–70° in the wavelength range of 200–1100 nm. These optical investigations demonstrate the antireflection characteristics of the InGaAs nanowires. Furthermore, piezoelectric responses were collected from the top of the vertically standing InGaAs nanowires at five different points using piezoelectric force microscopy. The measured area for one point was about 50 nm × 50 nm, and the piezoelectric responses of one or two InGaAs nanowires per point were expected to be measured, as the growth direction was along with the polar c -axis [0001] direction.

Magnetic skyrmions in heavy metal (HM)/CoFeB/MgO structures are of particular interest for skyrmion-based magnetic tunnel junction (MTJ) devices because of their reliable generation, stability and read-out through purely electrical methods. To optimize the properties, such as stability, a strong Dzyaloshinskii-Moriya interaction (DMI) is required at room temperature. Here, using first-principles calculations, we demonstrate that giant DMI can be obtained in Ir/CoFe structures with an Fe-terminated configuration. Moreover, Brillouin light scattering measurements show that indeed Ta/Ir/Co20Fe60B20/MgO thin films with perpendicular magnetic anisotropy exhibit a large DMI value (1.13 mJ/m2), which can be attributed to the smooth and Fe-rich interface between Ir and CoFeB layers. Furthermore, we observe stable sub-100 nm magnetic skyrmions at room temperature in Ir/CoFeB/MgO systems by magnetic force microscope. This work paves the way for promoting the application of skyrmions in CoFeB/MgO-based perpendicular anisotropy MTJ structures.

11 figures, 3 tables.-- Supplementary information available., The attrition behaviour of several promising oxygen carriers tested in Chemical Looping Combustion (CLC) units has been evaluated using an air-jet apparatus based on ASTM D5757 at 20 and 800 °C. Results were evaluated to determine a general testing procedure that allows estimating the adequacy at working temperature of a potential oxygen carrier. For both fresh and used oxygen carriers, attrition was lower when the temperature of the Air Jet attrition Index (AJI) test was increased. Thus, tests with potential oxygen carriers must be performed close to the temperature they are planned to be used to obtain reliable information. Results indicated that used oxygen carriers with AJI value at hot conditions between 1 and 2% showed long lifetimes under continuous CLC operation., This work was supported by the Spanish National Research Council (CSIC) through the international collaboration project i-LINK+ 1225. The authors would also thank the support of the European Regional Development Fund (ERDF) under the program “Programa Operativo FEDER Aragón 2014-2020 - Construyendo Europa desde Aragón: Proyecto BiosinCO2 (LMP180_18)” and of the ENE2017-89473-R AEI/FEDER, UE. T. Mendiara thanks for the “Ramón y Cajal” post-doctoral contract awarded by the Spanish Ministry of Economy and Competitiveness.

The objective of this study was to quantitatively analyze bubble/micro-bubble regime transition point in a bubble column. A test was carried out with a cylindrical stainless-steel column having an inner diameter of 0.097 m and a height of 1.8 m. An air was injected as a gas medium. Kerosene with a density of 800 kg/m3, viscosity of 1.64 x 10-3 Pa•s, and surface tension of 23 x 10-3 N/m at 20 ± 2 °C was used as a liquid. The experiment was conducted on a single nozzle plate with different hole sizes (0.7, 1.5, 2.0, and 3.46 mm). To analyze the standard deviation of the differential pressure signal by air bubbles separated from the jet, 12,000 differential pressure data from 0.05 m to 0.15 m of height were measured at 200 Hz under each condition. As gas velocity at the orifice increased, sizes of bubbles falling apart from the nozzle increased. Standard deviation of differential pressure also increased. Bubbles grew until they fell from the tip of the jet. At higher orifice gas velocity, the standard deviation of the differential pressure was reduced due to the occurrence of micro-bubbles. Since the standard deviation of the differential pressure showed a high peak at We/Reg-8 = 1.2 x 1045 for all cases, this value was selected as a demarcation of bubble/heterogeneous micro-bubble regime transition. The standard deviation of pressure drop fluctuation was the lowest at We/Reg-8 = 6.0 x 1048. This point was determined as the homogeneous micro-bubble regime point.

Although ceria particles are currently receiving great interest with their unique catalytic and optical properties, the problem of agglomeration is yet to be overcome, which is caused by their high density and surface energy, consequently hampering the practical applications. Herein, a novel method of preparing hierarchical shells of ceria (CeO2) and silica (SiO2) on a polystyrene (PS) core is introduced to control the shape and surface charge of the particle, which give rise to different dispersion conditions. The PS/CeO2/SiO2 hybrid core–shell microspheres provide a wide spectrum of surface charge via adjustment of the thickness of the outermost silica shell from 20 to 40 nm, which sets the isoelectric point (IEP) in the range of 5.1–8.6. Subsequently, the silica shell significantly extends the product’s stability and utilization windows due to the controlled surface charge and affinity between the particle surface and the dispersion medium. The developed multilayered core–shell microspheres and the method of synthesis have great potential for various applications that require sophisticated control of surface properties.

Periprosthetic joint infections that may occur when a prosthetic implant is inserted can cause serious problems in the human body. Infection by antibiotic-resistant bacteria is known to be difficult to treat because it can form a thick biofilm. This paper proposes a dual antibiotic delivery system capable of sustained release from a biodegradable material to treat periprosthetic joint infections caused by antibiotic-resistant bacteria. Three-dimensional printing technology was used to fabricate scaffolds incorporating dual antibiotics. A cylindrical biodegradable polymer scaffold capable of releasing antibiotics was prepared by homogeneously mixing tobramycin or vancomycin, or a mixture thereof, and combining with a ring-shaped metal scaffold. The release profile of the antibiotics released from the fabricated hybrid scaffold was measured by high performance liquid chromatography and the susceptibility of antibiotics confirmed using Staphylococcus aureus and Escherichia coli. In addition, non-cytotoxicity of the antibiotic-incorporated scaffolds was confirmed. In conclusion, we successfully fabricated a metal-polymer hybrid scaffold capable of sustained release of two antibiotics therefore, it is expected that metal-polymer hybrid scaffold provides promising treatment for periprosthetic joint infection.

The homogeneous-to-heterogeneous flow regime transition point dependence on gas and liquid properties was investigated in a semi-cylindrical bubble column of 1.8 m height and 0.21 m inner diameter operating as a semi-batch system. He, air, and CO2 gases were injected at superficial gas velocities of up to 239 mm/s. The batch liquids included water, aqueous ethanol solutions, and aqueous glycerol solutions, all with a gas-free liquid height settled at 1 m. When the gas density increased, the gas holdup increased at all superficial gas velocities, delaying the flow regime transition. The gas holdups in the liquid mixtures were higher than those for tap water. The transition gas holdup for the ethanol solutions increased to a sharp maximum and then decreased as the surface tension increased. Also, the glycerol solutions showed similar behavior with respect to increasing liquid viscosity, but with a shallower maximum. The transition gas holdup was empirically correlated as a function of the gas density, surface tension, and liquid viscosity, employing dimensional constants. The measured transition gas holdups for liquid mixtures, as well as some data from the literature, were fitted by the correlation.

This paper proposes an efficient simplified elastic–plastic analysis procedure using engineering formulas to perform strain-based fatigue design considering the plasticity that occurs in nuclear safety class 1 piping systems during severe seismic loads, and then presents the application results of the procedure to a pressurizer surge line system. The total strain amplitudes, fatigue assessment results, and total calculation time were compared between the proposed procedure and the detailed dynamic finite element elastic-plastic analysis. The comparison confirmed that the proposed analysis procedure can efficiently derive reasonable and conservative results for nuclear safety class 1 piping systems under severe seismic loads.

We report a multilayered hole transport layer (HTL) structure to improve the efficiencies and lifetimes of quantum dot light-emitting diodes (QD-LEDs). The HTL structure was constructed by inserting molybdenum trioxide (MoO3) into an organic monolayer to enhance its hole conductivity. We then investigated the effects of the multilayered HTL on the performance and operating lifetimes of QD-LEDs. QD-LEDs with optimal HTL exhibit power efficiency, external quantum efficiency, and lifetime (T80) of 10.19 lm/W, 9.66%, and 336 h, respectively. Compared to the monolayer structure, the lifetime of the multilayered HTL was enhanced by a factor of 15. This novel architecture for QD-LEDs with multilayered HTL offers a new design strategy for next-generation high-efficiency QLED displays and solid-state lighting technologies.

This paper investigates the effect of calcination temperature and duration on the cyclic CO2 capture performance of natural lime-based sorbents. Tests showed that increasing calcination temperature considerably reduced the sorbent reactivity over the first few calcination-carbonation cycles. No significant variation in performance was observed when a sorbent remained at the calcination temperature after completing limestone decomposition. On the other hand, incomplete limestone calcination significantly altered the sorbent cyclic utilization and CO2 carrying capacity. A semi-empirical method is proposed to estimate the fast reaction-controlled carbonation extent at different reaction cycles, calcination extents and temperatures. This method is shown to work well for two different naturally-derived limestones exposed to different calcination conditions.

The porous nanocomposite of layered double hydroxide (LDH) nanosheets and naturally abundant chitosan biopolymer was developed for facile uptake and selective release of cosmetic liposome capsules (50–200 nm). This study investigated the calcination-reconstruction method to obtain a well-organized and porous LDH/chitosan polymer structure. We used BET analysis and confocal fluorescence microscopy images to show the porous structure and anion-acceptable LDH surface of the nanocomposite. The nanocomposite exhibited a 64.4 m2/g BET surface area, which is eight times higher than commercial LDH particles. These properties allow for facile uptake and controlled release of large liposome particles, depending on the solution pH and anions. This result suggests that the nanocomposite polymer network effectively blocks liposome release. Moreover, we successfully reused collected nanocomposites several times after washing with ethanol to remove residual liposomes.

Based on the hydrodynamic characteristics at the layer inversion point in three-phase fluidized beds with binary solids, rod-to-bed heat transfer was investigated in a semi-cylindrical transparent column (0.21 m inner diameter and 1.8 m height) with polymer beads (diameter 3.3 mm, density 1280 kg/m3) and glass beads (diameter 0.385 mm, density 2500 kg/m3) as binary solids. Five solid volumetric ratios were investigated, with superficial liquid velocity ranging from 25.2 to 35.0 mm/s and superficial gas velocity from 0 to 12.4 mm/s. Due to the particle size effect, the heat transfer coefficient of the polymer beads was always larger than that of the glass beads for the fluid velocities tested. When the polymer bead fraction increased at the layer inversion point in three-phase fluidized beds, the heat transfer coefficient increased due to the solids holdup. For all volumetric ratios studied, increasing the superficial gas velocity led to a lower bed voidage and a higher heat transfer coefficient. When the polymer bead volumetric fraction increased in three-phase fluidized beds, the superficial liquid layer inversion velocity decreased.

We investigated whether the CSF cleft sign on ADC maps is beneficial for differentiating extra-axial tumors from intra-axial tumors. Seventy-seven intracranial tumor patients were reviewed. Visual grades of CSF cleft sign on T2WI and ADC were compared. The diagnostic performance of CSF cleft sign using ADC plus T2WI was compared with that using T2WI alone. A CSF cleft was more easily visualized on ADC (P

The effect of various biomass derived inhibitors (i.e. furfural, hydroxymethylfurfural (HMF), vanillin, 4-hydroxy benzaldehyde (4-HB) and acetate) was investigated for fatty acid accumulation in Rhodococcus sp. YHY 01. Rhodococcus sp. YHY01 was able to utilize acetate, vanillin, and 4-HB for biomass production and fatty acid accumulation. The IC50 value for furfural (3.1mM), HMF (3.2mM), vanillin (2.0mM), 4-HB (2.7mM) and acetate (3.7mM) was calculated. HMF and vanillin affect fatty acid composition and increase saturated fatty acid content. Rhodococcus sp. YHY 01 cultured with empty fruit bunch hydrolysate (EFBH) as the main carbon source resulted in enhanced biomass (20%) and fatty acid productivity (37%), in compression to glucose as a carbon source. Overall, this study showed the beneficial effects of inhibitory molecules on growth and fatty acid production, and support the idea of biomass hydrolysate utilization for biodiesel production by avoiding complex efforts to remove inhibitory compounds.

Arctic psychrotrophic bacterium Pseudomonas sp. PAMC 28620 was found to produce a distinctive medium-chain-length polyhydroxyalkanoate (MCL-PHA) copolymer when grown on structurally unrelated carbon sources including glycerol. The maximum MCL-PHA copolymer yield was obtained about 52.18±4.12% from 7.95±0.66g/L of biomass at 144h of fermentation when 3% glycerol was used as sole carbon and energy source during the laboratory-scale bioreactor process. Characterization of the copolymer was carried out using fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS), proton (1H) and carbon (13C) nuclear magnetic resonance spectroscopy (NMR), gel permeation chromatography (GPC), differential scanning calorimeter (DSC) and thermo-gravimetric analysis (TGA). The copolymer produced by Pseudomonas sp. PAMC 28620 consisting of four PHA monomers and identified as 3-hydroxyoctanoate (3HO), 3-hydroxydecanoate (3HD), 3-hydroxydodecanoate (3HDD) and 3-hydroxytetradecanoate (3HTD). An average molecular weight of the copolymer was found approximately 30.244kDa with polydispersity index (PDI) value of 2.05. Thermal analysis showed the produced MCL-PHA copolymer to be low-crystalline (43.73%) polymer with great thermal stability, having the thermal decomposition temperature of 230°C-280°C, endothermic melting temperature (Tm) of 172.84°C, glass transition (Tg) temperature of 3.99°C, and apparent melting enthalpy fusion (ΔHm) about 63.85Jg-1.

Cadaverine, a five carbon diamine (1,5-diaminopentane), plays a role as a building block of polyamides and it can be made by fermentation or direct bioconversion. To improve its production by increasing reusability of immobilized enzyme and avoid separation of enzyme in bioconversion, a continuous l -lysine bioconversion process for cadaverine production has been developed. Various divalent cations, alginate concentrations, cell density with alginate and flow rate of feed were examined to maximize the lysine decarboxylase activity of the whole-cell immobilized beads. Under the selected conditions, 123 h of continuous cadaverine production has been performed and 5.5 L of 819 mM cadaverine were produced with 14 mL reactor resulting in 466.5 g of cadaverine. Cadaverine production was possible with small volume reactor maintaining relatively high concentration of substrate.

Layer inversion in gas–liquid–solid fluidized beds with binary solids was examined in a semi-acrylic column of 1.8 m height and 0.21 m inner diameter. Binary solid combinations were composed of polymer beads (PB, dp=3.3 mm, ρs=1,280 kg/m3) and glass beads (GB, dp=0.385 mm, ρs=2500 kg/m3). Five volumetric ratios (PB:GB=0.67:0.33, 0.6:0.4, 0.5:0.5, 0.4:0.6, 0.33:0.67) were used with superficial liquid velocities of 21.6–34.2 mm/s, and superficial gas velocities of 0 to 16.6 mm/s. Bubble size, bed height, and superficial liquid velocity at the layer inversion point vary with the binary composition. Upon gas introduction into a liquid–solid fluidization column, the superficial liquid layer-inversion velocity increased if it occurred when there was initial bed contraction. On the other hand, the liquid layer inversion velocity decreased when there was initial bed expansion. For all binary solid combinations showing initial bed expansion, liquid layer-inversion velocity decreased with increasing superficial gas velocity in three-phase fluidization, consistent with the gas-perturbed liquid model.

A multi-purpose mid-plane manipulator system has been developed and installed at the mid-plane of the KSTAR vacuum vessel. The system serves as user facility which allows to cover various topics of researches in plasma-surface interaction (PSI) including material sample test and PSI diagnostic. The multi-purpose mid-plane manipulator system has a 4 m long cantilever structure with a 3 m long moving shaft. The system is equipped with a differential pumping system for the independent installation and removal of samples and diagnostic without vacuum break of KSTAR. The sample mounting head at the end of the shaft can reach the position of the outer boundary of ∼10 cm away from the last closed flux surface (LCFS). In this paper, selected PSI related experiments by using the manipulator are introduced.

A jet attrition model is developed to predict the evolution of the particle size distribution in fluidized beds. This model predicts changes in particle size distribution due to impact attrition in the jet region as a function of operating parameters – temperature, particle impact velocity and time. The model provides good agreement with experimental results for iron and hematite as oxygen carriers, with limestone and lime as CO2 sorbent at temperatures from 20 to 800 °C and jet velocities from 59 to 221 m/s. It is found that fragmentation, abrasion, and material fatigue over the attrition duration must be considered. Two fitting parameters considering fatigue by material properties and repeated collisions are applied in this model, with their values determined based on nonlinear least squares regression following the evolution of the particle size distribution.

To meet the growing demand for high-power lithium-ion batteries (LIBs), the development of advanced materials is crucial because they play a central role in energy storage technologies. Although graphite is widely used as the most popular anode material, the rate capability and thermal stability of graphite should be further improved for extending the applications of LIBs into emerging markets like electric vehicles and personal mobility devices. With this in mind, we propose off-stoichiometric TiO2-x-decorated graphite as a potential anode material for practical use in high-power LIBs. Thanks to the high electrical conductivity and thermal resistance of off-stoichiometric TiO2-x induced by an in situ carbothermal reduction process, the rate capability and thermal stability of graphite can be notably enhanced. The TiO2-x-decorated graphite offers a high capacity retention of 76.9% even after 100 cycles at a current density of 1C. We believe that this work can provide more opportunities to explore highly reliable anode materials offering high-energy and high-power characteristics for advanced LIBs.

The luminescent down-shifting (LDS) layer, which transforms incoming high energy solar photons to visible ones, promises augmentation of both photoelectric performance and aesthetic appeals of photovoltaic (PV) modules. For efficient, colored PVs with LDS layer, luminophores with high photoluminescence quantum yield (PL QY), small overlap between absorption and emission spectra, and proven photostability are prerequisites. Here, we demonstrate colorful, opaque PV modules with LDS layers of minimized photon sacrifice enabled by structurally-engineered, eco-friendly InP/ZnSexS1-x quantum dots (QDs). Specifically, composition-controlled, thick shells allow enhanced absorption in the UV region and improved PL QY of QDs. Additionally, the ligand-engineering guarantees the stability of LDS layers after the damp heat test. Benefited from QD-LDS layers, commercially available CIGS and c-Si PV modules are awarded with 40% EQE enhancement in the ultraviolet region and wide-ranging color tunability over the entire visible region by QD-LDS layers. Hence, this integrated approach for desirable luminophores will contribute to the realization of highly-efficient, aesthetically-appealing opaque PV modules.

Organic matter and nutrient in the pre-treated swine wastewater by electron beam irradiation was treated using an ion-exchange biological reactor (IEBR). To evaluate the solubilization of organic matter by electron beam irradiation, carbohydrates, proteins and lipids were analyzed. The optimal dose for the solubilization of organic matter in swine wastewater ranged 20 – 75 kGy . Most of solubilized organic fractions were proteins and lipids. The solubilized proteins and lipids were effectively used as electron donors for denitrification. The maximum chemical oxygen demand (COD) removal efficiency was 85.1% at an organic loading rate of 1.4 kg/m 3 ·day and electron beam irradiation dose of 75 kGy . For nitrogen, the nitrogen removal was highly dependent upon the current density. The maximum total nitrogen removal efficiency was 75.0% at 1.09 A/m 2 . Amorphous phosphorus precipitation was formed in the IEBR, because calcium ions outcompeted magnesium.

We fabricated a pixelated silicon sensor with a junction field effect transistor (JFET) on a 650 μ m thick, high-resistivity ( > 5 k Ω ⋅ cm) n-type double-sided polished 6-in. silicon wafer using a double-sided fabrication process. The JFET, which had a cylindrical structure, acted as a switch to read out charges accumulated in the pixelated sensor. We investigated the electrical characteristics of the pixelated sensor, which had a size of 100 μ m × 100 μ m . We also measured the drain current as a function of the drain voltage for different gate voltages to examine the switching performance of the JFET and optimized the design parameters of the pixelated sensor for the proper functioning of the switch. Furthermore, the pixelated sensor’s responses under illumination by a light-emitting diode and X-rays were measured. The electrical characteristics and responses of the pixelated sensors are presented in this paper.