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A data‐driven model for predicting the surface temperature using neural networks was proposed to alleviate the computational burden of numerical weather prediction (NWP). Our model, named TPTNet uses only 2 m temperature measured at the weather stations of the South Korean Peninsula as input to predict the local temperature at finite forecast hours. The turbulent fluctuation component of the temperature was extracted from the station measurements by separating the climatology component accounting for the yearly and daily variations. The effect of station altitude was then compensated by introducing a potential temperature. The resulting turbulent potential temperature (TPT) data at irregularly distributed stations were used as input for predicting the TPT at forecast hours through three trained networks based on convolutional neural network, Swin Transformer, and a graph neural network. By comparing the prediction performance of our network with that of persistence and NWP, we found that our model can make predictions comparable to NWP for up to 12 hr. Plain Language Summary: We developed a new model called TPTNet to predict local temperatures using only temperature measurements from weather stations in South Korea. This model aims to reduce the heavy computational demands of traditional numerical weather prediction (NWP) methods. By analyzing 20 years of data, we separated the regular temperature patterns that change yearly and daily from the more unpredictable fluctuations. We also adjusted the model for the altitude of each weather station. We trained three different types of neural networks for this purpose: a convolutional neural network, a Swin Transformer, and a graph neural network. When we tested our model with new data from 2020, it made reliable temperature predictions for up to 12 hr, performing as well as, or even better than, traditional NWP methods. This new approach could help improve weather forecasting by making it faster and less computationally intensive. Key Points: Only 2 m temperature data measured at the weather station is used as input for the prediction of temperature at finite forecast hoursTurbulent fluctuation temperature relative to the climatological yearly and daily periodic variations with the altitude adjustment using potential temperature is considered in data‐driven learningFor 12 hr of forecast hour, TPTNet produces forecasts comparable to those of the numerical weather prediction, with the less scattered errors over stations [ABSTRACT FROM AUTHOR]

Hemoglobin recovered from slaughterhouse blood has proven to be an effective flocculant of negatively charged particulate contaminants, but it is ineffective against positively charged contaminants. Phosphorylation is useful for modifying proteins to increase the number of negatively charged sites. Dry‐heat phosphorylation and chemical phosphorylation were applied to hemoglobin. The kaolin/hematite clarification efficiencies of modified hemoglobin at different dosages and pH values were determined. ζ‐potential and total phosphorus content were also measured. Chemical phosphorylation was generally more effective than dry heat phosphorylation at achieving the desired modification of properties; it produced modified hemoglobin (CPhosHb) with higher phosphorus content and lower isoelectric point, and it had greater efficiency in flocculating hematite suspensions. At the optimal dosage of 5 mg/g hematite, treatment with CPhosHb resulted in a 99% turbidity reduction in the hematite suspension after 24 h. When 500 mM calcium chloride was applied to CPhosHb, it exhibited a positive charge in the overall pH range and was capable of clarifying suspensions of negatively charged kaolin particles at low doses. From these results, the effectiveness of chemical phosphorylation on hemoglobin is demonstrated and CPhosHb can be used as a flocculant of either negatively charged or positively charged contaminants in wastewater. [ABSTRACT FROM AUTHOR]

Metal‐air batteries as alternatives to the existing lithium‐ion battery are becoming increasingly attractive sources of power due to their high energy‐cost competitiveness and inherent safety; however, their low oxygen evolution and reduction reaction (OER/ORR) performance and poor operational stability must be overcome prior to commercialization. Herein, it is demonstrated that a novel class of hydrothermally grown dual‐phase heterogeneous electrocatalysts, in which silver‐manganese (AgMn) heterometal nanoparticles are anchored on top of 2D nanosheet‐like nickel vanadium oxide (NiV2O6), allows an enlarged surface area and efficient charge transfer/redistribution, resulting in a bifunctional OER/ORR superior to those of conventional Pt/C or RuO2. The dual‐phase NiV2O6/AgMn catalysts on the air cathode of a zinc‐air battery lead to a stable discharge–charge voltage gap of 0.83 V at 50 mA cm−2, with a specific capacity of 660 mAh g−1 and life cycle stabilities of more than 146 h at 10 mA cm−2 and 11 h at 50 mA cm−2. The proposed new class of dual‐phase NiV2O6/AgMn catalysts are successfully applied as pouch‐type zinc‐air batteries with long‐term stability over 33.9 h at 10 mA cm−2. [ABSTRACT FROM AUTHOR]

Solution‐processed transition metal oxides (TMOs) prepared from complex ion precursors are developed as promising scalable interfacial layers for non‐fullerene organic photovoltaics (OPVs); however, challenges remain in achieving defect‐free and highly oriented metal‐oxygen networks without post‐deposition treatments due to the presence of residual organic metal‐binding ligands in films. Herein, the novel strategy that the problematic organic metal‐binding ligands in TMO precursors can be successfully eliminated by an anion‐induced catalytic reaction (ACR) at room temperature is demonstrated, in which the low‐level anions induce electron redistribution and instability of TMO precursors, expediting binding ligand removal during the hydrolysis reaction. The subsequent condensation process facilitates a dimensionally confined and continuous metal‐oxygen network with a 20‐fold increase in electrical conductivity (from 8.4 × 10−4 to 1.8 × 10−2 S m−1) and superior work function tunability (from 5.1 to 5.3 eV) compared to the pristine film. The ACR‐derived TMO thin film on top of a ternary PBDB‐TF:Y6:PC71BM photoactive layer enables an inverted device configuration with improved efficiency of 17.6%, as well as enhanced stability over 70% of the initial efficiency for up to 100 h AM 1.5G illumination. [ABSTRACT FROM AUTHOR]

Using the density functional methods B3LYP, M06‐2X, PBE1PBE, B3LYP D3, M06‐2X D3, and PBE1PBE D3, and the ab initio MP2 calculations, the optimized atomic structures and energies of C20 cage rotation isomers without a constraint were obtained. The reaction path between the two rotational isomers was then studied, in which there are three local stable atomic structures. One is the most stable fullerene structure with the D2h point group staggered between the upper and bottom pentagons (ST) and the other is the second lowest energy rotational isomer with the Cs point group eclipsed between the upper and bottom pentagons (EC) with a torn fullerene structure (M1) between ST and EC. The first transition structure T1 between the ST and the M1, and the second transition structure T2 between the M1 and the EC were then obtained along the reaction coordinate between these three structures. Vibration analysis of all optimized structures including the transition structures without a constraint was carried out. For each of the rotational isomers obtained by our calculations, thermodynamic stability was explained with the relative energy difference, and then the kinetic stability was analyzed as the HOMO–LUMO energy difference. [ABSTRACT FROM AUTHOR]

We have studied the fragmentation of C60 fullerenes in a single wall carbon nanotube using the molecular dynamic simulations combined with the empirical‐tight‐binding total‐energy‐calculation method. We show the chemical binding structure of carbon nanopeapod (CNP) comprised of single‐wall carbon nanotube (SWNT) and C60 fullerene molecule and the geometrical spatial positioning structure of C60 inside in the SWNT as a function of dynamic time for 2 ps at each temperature of 4000, 5000, and 6000 K. Therefore, using the snapshots, it could be shown that one is consistent with a previous study that the passage of thermal conductivity in the CNP is mainly transmitted through C60 rather than CNT, and the other is to carefully suggest that the scenario in which C60@SWNT forms a double‐walled carbon nanotube is followed by the destruction of C60 after the combination of C60 and SWNT is made in the early stages. [ABSTRACT FROM AUTHOR]

We investigated the decomposition pattern of three C20 carbon isomer clusters using molecular dynamics simulations combined with the empirical tight-binding total energy calculation method. Here, the thermodynamic behaviors show up for 2 ps. Dynamic behavior is researched by considering the change in assembly energy, bond distance distribution, total energy, and potential energy as a function of temperature. The bonds start breaking around 3300, 4500, and 5100 K for cage, bowl, and ring isomers, respectively. Once a bond is broken, strain accumulates on the neighbors of that atom, and bond cleavage is further accelerated at the neighboring atoms. Based on the snapshots of decomposition, we suggest a C20 formation scenario from linear carbon clusters to ring, bowl, or cage isomers. [ABSTRACT FROM AUTHOR]

A 6–18 GHz gallium nitride (GaN) non‐uniform distributed amplifier (NDA) monolithic microwave integrated circuit with high power density is implemented with compact four‐way combined power. The drain lines and gate lines are shared among the combined NDAs. Sharing drain (or gate) lines reduces the drain (or gate) line length by half, while keeping the same characteristic impedances and eliminates bulky and lossy power combiners, such as Wilkinson combiners. The proposed four‐way NDA was fabricated using a commercial 0.25 μm GaN high electron mobility transistor (HEMT) process. It shows average continuous wave output power of 20.8 W and average associated gain of 10.7 dB from 6 to 18 GHz under 33 V drain bias. When pulsed input power and pulsed DC bias are simultaneously supplied to the NDA, the output power increases to 26 W, on average. To the best of the authors' knowledge, the highest RF power and power density among the reported GaN power amplifiers with an octave bandwidth higher than the Ku‐band is represented in this work. [ABSTRACT FROM AUTHOR]

Orchid colored powder samples of Cs2AgF4 were prepared by a solid state reaction from CsF and AgF2. The diffuse reflectance spectrum of a powder sample of Cs2AgF4 was measured in the UV/Vis region. It shows three broad bands, two in the visible-light region at 650 nm, 500 nm and one in the UV region at 259 nm. The bands are assigned to F 2p → Ag 4d and Ag 4d → Ag 4d transitions. The optical band gap for Cs2AgF4 determined from the UV/Vis diffuse reflectance spectrum is approx. 2.17 eV. In order to interpret the observed absorptions, the theoretical absorption spectrum of Cs2AgF4 was obtained from density functional calculations. [ABSTRACT FROM AUTHOR]

SUMMARY In this work, we studied the peristaltic flow of a Jeffrey-six constant fluid in a uniform tube. The governing equations of the Jeffrey-six constant fluid were simplified by using the assumptions of long wave length and low Reynolds number approximation. The simplified form of equations were solved using the perturbation, homotopy analysis and finite difference methods. The comparison of the three solutions are shown graphically. The variation of pressure rise and frictional forces with the different parameters were also examined numerically. Results are presented at the end of the article. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

GLO:1CJF/01nov19:bkcs11868-fig-0001.jpg PHOTO (COLOR): Structures of a single-walled carbon nanotube (SWNT) and (C60)2 fullerene dimer molecule (length unit: å). Figure shows the geometrical spatial arrangement of the (C SB 60 sb ) SB 2 sb fullerene dimer molecule inside the SWNT indicating the unit cell of CNP under the periodic condition for TBMD simulation as a function of dynamic time; that is, for 12.744 ps at the temperature of 5000 K. If you take a closer look at this process, the separate (C SB 60 sb ) SB 2 sb fullerene dimer molecules form a single bond between C SB 60 sb fullerene, the carbon atoms from the C SB 60 sb fullerene move to a different C SB 60 sb fullerene to form a new bond, and as the C SB 60 sb fullerene and the broken, the carbon pieces form a new bond with the other C SB 60 sb fullerene, gradually forming a small capped carbon nanotube. [Extracted from the article]

Orchid colored powder samples of Cs2AgF4 were prepared by a solid state reaction from CsF and AgF2. The diffuse reflectance spectrum of a powder sample of Cs2AgF4 was measured in the UV/Vis region. It shows three broad bands, two in the visible-light region at 650 nm, 500 nm and one in the UV region at 259 nm. The bands are assigned to F 2p → Ag 4d and Ag 4d → Ag 4d transitions. The optical band gap for Cs2AgF4 determined from the UV/Vis diffuse reflectance spectrum is approx. 2.17 eV. In order to interpret the observed absorptions, the theoretical absorption spectrum of Cs2AgF4 was obtained from density functional calculations. [ABSTRACT FROM AUTHOR]

The title compound is synthesized by solid state reaction of stoichiometric amounts of AgF2 and CsF (Pt ampule, 600 K, 24 h) and characterized by UV/VIS diffuse reflectance spectroscopy and DFT calculations. [ABSTRACT FROM AUTHOR]