Process simulation using mathematical modeling tools is becoming more common in the pharmaceutical industry. A mechanistic model is a mathematical modeling tool that can enhance process ...understanding, reduce experimentation cost and improve product quality. A commonly used mechanistic modeling approach for powder is the discrete element method (DEM). Most pharmaceutical materials have powder or granular material. Therefore, DEM might be widely applied in the pharmaceutical industry. This review focused on the basic elements of DEM and its implementations in pharmaceutical manufacturing simulation. Contact models and input parameters are essential elements in DEM simulation. Contact models computed contact forces acting on the particle-particle and particle-geometry interactions. Input parameters were divided into two types-material properties and interaction parameters. Various calibration methods were presented to define the interaction parameters of pharmaceutical materials. Several applications of DEM simulation in pharmaceutical manufacturing processes, such as milling, blending, granulation and coating, were categorized and summarized. Based on this review, DEM simulation might provide a systematic process understanding and process control to ensure the quality of a drug product.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Biological cellular structures have inspired many scientific disciplines to design synthetic structures that can mimic their functions. Here, we closely emulate biological cellular structures in a ...rationally designed synthetic multicellular hybrid ion pump, composed of hydrogen-bonded EMIM
TFSI
ion pairs on the surface of silica microstructures (artificial mechanoreceptor cells) embedded into thermoplastic polyurethane elastomeric matrix (artificial extracellular matrix), to fabricate ionic mechanoreceptor skins. Ionic mechanoreceptors engage in hydrogen bond-triggered reversible pumping of ions under external stimulus. Our ionic mechanoreceptor skin is ultrasensitive (48.1-5.77 kPa
) over a wide spectrum of pressures (0-135 kPa) at an ultra-low voltage (1 mV) and demonstrates the ability to surpass pressure-sensing capabilities of various natural skin mechanoreceptors (i.e., Merkel cells, Meissner's corpuscles, Pacinian corpuscles). We demonstrate a wearable drone microcontroller by integrating our ionic skin sensor array and flexible printed circuit board, which can control directions and speed simultaneously and selectively in aerial drone flight.
•Mobility of As increases in the presence of Fe(II) under anoxic conditions•As mobility varies due to the dissolution or re-precipitation of Fe minerals•Repetition of redox cycle may cause As to ...adversely affect the environment
Changes in the saturation degree of aquifers control the geochemical reactions of redox-sensitive elements such as iron (Fe), sulfur (S), and arsenic (As). In this study, the effects of redox conditions and the presence of Fe and S on the behavior of As in a soil environment were investigated by observation in a batch experimental system. Arsenic was stable on Fe(III) solid surface in an oxidizing environment but was easily released into the aqueous phase following the reductive dissolution of Fe during an anoxic period. The alternating redox cycles led to a change in the concentrations of Fe, S, and As in both the aqueous and solid phases. The composition of Fe minerals changed to a less crystalline phase while that of solid phase As changed to a more reduced phase in both the As-contaminated natural soil and FeS-amended soil batch systems. This tendency was more prominent in the batch containing higher amounts of total Fe and S. These results show that a redox cycle can increase the possibility of As contamination of groundwater during dissolution and reprecipitation of Fe minerals and simultaneous microbial reduction of S and/or As species.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this work, copper nanowires (NWs) and Cu nanoparticles (NPs) were employed to increase the reliability of a printed electrode pattern under mechanical bending fatigue. The fabricated Cu NW/NP inks ...with different weight fractions of Cu NWs were printed on a polyimide substrate and flash light-sintered within a few milliseconds at room temperature under ambient conditions. Then, 1000 cycles of outer and inner bending fatigue tests were performed using a lab-made fatigue tester. The flash light-sintered Cu NW/NP ink film with 5 wt % Cu NWs prepared under the flash light-sintering conditions (12.5 J·cm–2 irradiation energy, 10 ms pulse duration, and one pulse) showed a lower resistivity (22.77 μΩ·cm) than those of the only Cu NPs and Cu NWs ink (94.01 μΩ·cm and 104.15 μΩ·cm, respectively). In addition, the resistance change (ΔR·R 0 –1) of the 5 wt % Cu NWs Cu NW/NP film was greatly enhanced to 4.19 compared to the 92.75 of the Cu NPs film obtained under mechanical fatigue conditions over 1000 cycles and an outer bending radius of 7 mm. These results were obtained by the densification and enhanced mechanical flexibility of flash light-sintered Cu NW/NP network, which resulted in prevention of crack initiation and propagation. To characterize the Cu NW/NP ink film, X-ray diffraction and scanning electron microscopy were used.
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IJS, KILJ, NUK, PNG, UL, UM
In this work, bimodal Cu nano-inks composed of two different sizes of Cu nanoparticles (NPs) (40 and 100 nm in diameter) were successfully sintered with a multi-pulse flashlight sintering technique. ...Bimodal Cu nano-inks were fabricated and printed with various mixing ratios and subsequently sintered by a flash light sintering method. The effects of the flashlight sintering conditions, including irradiation energy and pulse number, were investigated to optimize the sintering conditions. A detailed mechanism of the sintering of bimodal Cu nano-ink was also studied via real-time resistance measurement during the sintering process. The sintered Cu nano-ink films were characterized using x-ray photoelectron spectroscopy and scanning electron microscopy. From these results, it was found that the optimal ratio of 40-100 nm NPs was found to be 25:75 wt%, and the optimal multi-pulse flash light sintering condition (irradiation energy: 6 J cm−2, and pulse duration: 1 ms, off-time: 4 ms, and pulse number: 5) was found. The optimally sintered Cu nano-ink film exhibited the lowest resistivity of 5.68 cm and 5B adhesion level.
Redox mediators (RMs) are considered an effective countermeasure to reduce the large polarization in lithium‐oxygen batteries. Nevertheless, achieving sufficient enhancement of the cyclability is ...limited by the trade‐offs of freely mobile RMs, which are beneficial for charge transport but also trigger the shuttling phenomenon. Here, we successfully decoupled the charge‐carrying redox property of RMs and shuttling phenomenon by anchoring the RMs in polymer form, where physical RM migration was replaced by charge transfer along polymer chains. Using PTMA (poly(2,2,6,6‐tetramethyl‐1‐piperidinyloxy‐4‐yl methacrylate)) as a polymer model system based on the well‐known RM tetramethylpiperidinyloxyl (TEMPO), it is demonstrated that PTMA can function as stationary RM, preserving the redox activity of TEMPO. The efficiency of RM‐mediated Li2O2 decomposition remains remarkably stable without the consumption of oxidized RMs or degradation of the lithium anode, resulting in an improved performance of the lithium‐oxygen cell.
The shuttling phenomenon is the most severe drawback of redox mediators (RMs) in lithium‐oxygen batteries, caused by the freely mobile nature of RMs. The shuttle effect was eliminated by anchoring RMs on the air electrode in form of a polymer. Successful prevention of the shuttle effect results in a remarkable improvement of the lithium‐oxygen cell‐performance.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
To ensure system reliability against unexpected and sudden disturbances, system operators must secure a portion of the transmission capacity of the power system as transmission reserve, which is not ...used under normal conditions. However, with the recent increase in renewable energy penetration, a transmission reliability margin has been employed under both conditions of system failures and normal operation conditions due to renewable energy uncertainty. Therefore, in the process of transmission pricing, the degree of use of the transmission facilities due to renewable energy uncertainty and system failures should be examined. This paper proposes transmission pricing using usage and reliability contribution factors, which are computed using the degree of use of the transmission lines over all periods. The probabilistic power flow is applied to consider changes in line flows through the forecasting error of renewable energy sources (RES). The proposed method is tested with an IEEE-5 bus system and an IEEE-24 bus system. The test results demonstrate the effectiveness of the proposed method in reasonably allocating transmission costs to network users, taking into account the reliability contribution due to system failures and renewable energy uncertainty.
Butyrate is a bacterial metabolite of dietary fiber in the colon that has been used to treat inflammatory disease. However, the effect of oral supplementation with butyrate on colitis has not been ...fully explored. We evaluated the effects of and mechanisms underlying oral supplementation with butyrate on experimental murine colitis. In an in vitro study, we found that LPS induced the secretion of cytokines (i.e., IL-8 in COLO 205; TNF-α, IL-6, IL-12, and IL-10 in RAW 264.7; and TNF-α, IL-6 and IL-12 in peritoneal macrophages obtained from IL-10-deficient IL-10−/− mice). Butyrate (100μM and 500μM) inhibited pro-inflammatory cytokine production (i.e., IL-8 in COLO205 and TNF-α, IL-6 and IL-12 in macrophages) but promoted anti-inflammatory cytokine (i.e., IL-10) production in RAW264.7 cells. Butyrate attenuated both the LPS-induced degradation/phosphorylation of IκBα and DNA binding of NF-κB and enhanced histone H3 acetylation. To confirm that butyrate played a protective role in colitis, an acute colitis model was induced using dextran sulfate sodium (DSS) and a chronic colitis model was induced in IL-10−/− mice. The administration of oral butyrate (100mg/kg) significantly improved histological scores in both colitis models, including the IL-10−/− mice. In immunohistochemical staining, IκBα phosphorylation was attenuated, and histone H3 acetylation was reversed in the treated colons of both colitis models. Our results indicate that oral supplementation with butyrate attenuates experimental murine colitis by blocking NF-κB signaling and reverses histone acetylation. These anti-colitic effects of butyrate were IL-10-independent. Butyrate may therefore be a therapeutic agent for colitis.
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•Butyrate inhibits the production of TNF-α, IL-6 and IL-12 in macrophages.•Butyrate inhibits NF-κB signaling and histone deacetylation in IEC and macrophages.•Oral supplementation with butyrate suppressed colitis, even in IL-10−/− mice.•Butyrate attenuated IκBα phosphorylation and histone H3 deacetylation in the colon.•The anti-inflammatory effect of butyrate is IL-10 independent.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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•We performed the two-step flash light sintering for copper nanoparticle ink to remove substrate warping.•12J/cm2 of preheating and 7J/cm2 of main sintering energies were determined ...as optimum conditions to sinter the copper nanoparticle ink.•The resistivity of two-step sintered copper nanoparticle ink was 3.81μΩcm with 5B adhesion level, 2.3 times greater than that of bulk copper.•The two-step sintered case showed a high conductivity without any substrate warping.
A two-step flash light sintering process was devised to reduce the warping of polymer substrates during the sintering of copper nanoparticle ink. To determine the optimum sintering conditions of the copper nanoparticle ink, the flash light irradiation conditions (pulse power, pulse number, on-time, and off-time) were varied and optimized. In order to monitor the flash light sintering process, in situ resistance and temperature monitoring of copper nanoink were conducted during the flash light sintering process. Also, a transient heat transfer analysis was performed by using the finite-element program ABAQUS to predict the temperature changes of copper nanoink and polymer substrate. The microstructures of the sintered copper nanoink films were analyzed by scanning electron microscopy. Additionally, an X-ray diffraction and Fourier transform infrared spectroscopy were used to characterize the crystal phase change of the sintered copper nanoparticles. The resulting two-step flash light sintered copper nanoink films exhibited a low resistivity (3.81μΩcm, 2.3 times of that of bulk copper) and 5B level of adhesion strength without warping of the polymer substrate.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
To reduce the risk of collision in territorial sea areas, including trade ports and entry waterways, and to enhance the safety and efficiency of ship passage, the International Maritime Organization ...requires the governing body of every country to establish and operate a vessel traffic service (VTS). However, previous studies on risk prediction models did not consider the locations of near collisions and actual collisions and only employed a combined collision risk index in surveillance sea areas. In this study, we propose a regional collision risk prediction system for a collision area considering spatial patterns using a density-based spatial clustering of applications with noise (DBSCAN). Furthermore, a fuzzy inference system based on a near collision (FIS-NC) and long short-term memory (LSTM) is adopted to help a vessel traffic service operator (VTSO) make timely optimal decisions. In the local spatial pattern stage, the ship trajectory was determined by identifying the actual-collision and near-collision locations simultaneously. Finally, the system was developed by learning a sequence dataset from the extracted trajectory of the ship when a collision occurred. The proposed system can recommend an action faster than the fuzzy inference system based on the near-collision location. Therefore, using the developed system, a VTSO can quickly predict ship collision risk situations and make timely optimal decisions at dangerous surveillance sea areas.
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