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The use of lithium metal either in an anode or anode-free configuration is envisaged as the most promising way to boost the energy density of the current lithium-ion battery system. Nevertheless, t...

In this study, polyolefin elastomer (POE) was blended with a chemically modified hydrocarbon resin (m-HCR), which was modified through a simple radical grafting reaction using γ-methacryloxypropyl trimethoxy silane (MTS) as an adhesion promotor to the glass surface, to design an adhesion-enhanced polyolefin encapsulant material for photovoltaic modules. Its chemical modification was confirmed by 1H and 29Si NMR and FT-IR. Interestingly, the POE blends with the m-HCR showed that the melting peak temperature (Tm) was not changed. However, Tm shifted to lower values with increasing m-HCR content after crosslinking. Additionally, the mechanical properties did not significantly differ with increasing m-HCR content. Meanwhile, with increasing m-HCR content in the POE blend, the peel strength increased linearly without sacrificing their transmittance. The test photovoltaic modules comprising the crosslinked POE blend encapsulants showed little difference in the electrical performance after manufacturing. After 1000 h of damp-heat exposure, no significant power loss was observed.

Pandemic and endemic strains of Vibrio cholerae arise from toxigenic conversion by the CTXφ bacteriophage, a process by which CTXφ infects nontoxigenic strains of V. cholerae. CTXφ encodes the cholera toxin, an enterotoxin responsible for the watery diarrhea associated with cholera infections. Despite the critical role of CTXφ during infections, signals that affect CTXφ-driven toxigenic conversion or expression of the CTXφ-encoded cholera toxin remain poorly characterized, particularly in the context of the gut mucosa. Here, we identify mucin polymers as potent regulators of CTXφ-driven pathogenicity in V. cholerae. Our results indicate that mucin-associated O-glycans block toxigenic conversion by CTXφ and suppress the expression of CTXφ-related virulence factors, including the toxin co-regulated pilus and cholera toxin, by interfering with the TcpP/ToxR/ToxT virulence pathway. By synthesizing individual mucin glycan structures de novo, we identify the Core 2 motif as the critical structure governing this virulence attenuation. Overall, our results highlight a novel mechanism by which mucins and their associated O-glycan structures affect CTXφ-mediated evolution and pathogenicity of V. cholerae, underscoring the potential regulatory power housed within mucus.

Bacterial cellulose (BC) has outstanding physical and chemical properties, including high crystallinity, moisture retention, and tensile strength. Currently, the major producer of BC is Komagataeibacter xylinus. However, due to limited tools of expression, this host is difficult to engineer metabolically to improve BC productivity. In this study, a regulated expression system for K. xylinus with synthetic ribosome binding site (RBS) was developed and used to engineer a BC biosynthesis pathway. A synthetic RBS library was constructed using green fluorescent protein (GFP) as a reporter, and three synthetic RBSs (R4, R15, and R6) with different strengths were successfully isolated by fluorescence-activated cell sorting (FACS). Using synthetic RBS, we optimized the expression of three homologous genes responsible for BC production, pgm, galU, and ndp, and thereby greatly increased it under both static and shaking culture conditions. The final titer of BC under static and shaking conditions was 5.28 and 3.67 g/l, respectively. Our findings demonstrate that reinforced metabolic flux towards BC through quantitative gene expression represents a practical strategy for the improvement of BC productivity.

Bacterial cellulose nanofiber (CNF) is a polymer with a wide range of potential industrial applications. Several Komagataeibacter species, including Komagataeibacter xylinus as a model organism, produce CNF. However, the industrial application of CNF has been hampered by inefficient CNF production, necessitating metabolic engineering for the enhanced CNF production. Here, we present complete genome sequence and a genome-scale metabolic model KxyMBEL1810 of K. xylinus DSM 2325 for metabolic engineering applications. Genome analysis of this bacterium revealed that a set of genes associated with CNF biosynthesis and regulation were present in this bacterium, which were also conserved in another six representative Komagataeibacter species having complete genome information. To better understand the metabolic characteristics of K. xylinus DSM 2325, KxyMBEL1810 was reconstructed using genome annotation data, relevant computational resources and experimental growth data generated in this study. Random sampling and correlation analysis of the KxyMBEL1810 predicted pgi and gnd genes as novel overexpression targets for the enhanced CNF production. Among engineered K. xylinus strains individually overexpressing heterologous pgi and gnd genes, either from Escherichia coli or Corynebacterium glutamicum, batch fermentation of a strain overexpressing the E. coli pgi gene produced 3.15 g/L of CNF in a complex medium containing glucose, which was the best CNF concentration achieved in this study, and 115.8% higher than that (1.46 g/L) obtained from the control strain. Genome sequence data and KxyMBEL1810 generated in this study should be useful resources for metabolic engineering of K. xylinus for the enhanced CNF production.

We report fluorescent deep-blue organic light emitting diodes (OLEDs) with significantly high efficiency by enhancing singlet exciton generation via triplet-triplet annihilation (TTA). Here, electron transport layers (ETL) and exciton blocking layers (EBL) with different characteristics (especially mobility) are applied to increase singlet harvesting (using TTA process) through appropriate charge carrier injection in the emissive layer. OLED with high electron mobility ETL, 1,4-bis(2-phenyl-1,10-phenanthrolin-4-yl)benzene (p-bPPhenB) and high hole mobility EBL, 9,9-dimethyl-10-(9-phenyl-9H-carbazol-3-yl)-9,10-dihydroacridine (PCzAc) exhibit relatively high external quantum efficiency of 9.18% with deep-blue color coordinates of (0.135, 0.115) at the luminance of 1000 cd/m2 and low driving voltage (4.5 V). The transient electroluminescence measurements are conducted to investigate the relation between prompt fluorescence from the initial singlet excitons and delayed fluorescence from the TTA process. This analysis shows significant enhancement in the singlet exciton generation by TTA process and charge recombination rate.

In this paper, we report a full-color reflective display device by combining reflective electrochromic device (ECD) and different color production units (conventional color filter (CF) and transmittance controllable electrochromic color filter (TCECF)). A full-color reflective device with TCECF showed an excellent diffuse reflectance of 47.2% in the white state owing to the high transmittance of TCECF in the bleached state than that of CF (19.5%). This device structure can easily provide various colors with high brightness and saturation with a broad grayscale. Particularly, in the colored state, TCECF and CF-based full-color reflective device displayed color coordinates of (0.59, 0.34), (0.31, 0.66), (0.24, 0.30) and (0.65, 0.33), (0.27, 0.61), (0.15, 0.06), for red, green and blue, respectively, and alongside also exhibited color gamut of 36.8% (for TCECF) and 73.1% (for CF) for full color reflective devices.

Using a simple esterification reaction of a hydroxyl group with an anhydride group, pristine lignin was successfully converted to a new lignin (COOH-lignin) modified with a terminal carboxyl group. This chemical modification of pristine lignin was confirmed by the appearance of new absorption bands in the FT-IR spectrum. Then, the pristine lignin and COOH-lignin were successfully incorporated into a poly(lactic acid) (PLA) matrix by a typical melt-mixing process. When applied to the COOH-lignin, interfacial adhesion performance between the lignin filler and PLA matrix was better and stronger than pristine lignin. Based on these results for the COOH-lignin/PLA biocomposites, the cost of printing PLA 3D filaments can be reduced without changing their thermal and mechanical properties. Furthermore, the potential of lignin as a component in PLA biocomposites adequate for 3D printing was demonstrated.

Bacterial cellulose (BC) has outstanding physical and chemical properties, including high crystallinity, moisture retention, and tensile strength. Currently, the major producer of BC is

The dissolution of transition metals (TMs) from LiMO2 (M = Ni, Co, Mn) cathodes and their subsequent side reactions on the anode and in the electrolyte result in Li-ion battery capacity and power losses. Despite the importance of this process, the lack of adequate analysis methods for tracking the subtle compositional changes at specific locations with nano-meter spatial resolution has prevented the elucidation of its microstructural origin and mechanism. Herein, we studied the dissolution of TMs from a Ni-rich layered cathode and investigated their deposition on a graphite anode and reactions with the electrolyte, with focus on the microstructural aspects. Changes in TM and oxygen contents in Ni-rich LiNi0.87Co0.09Mn0.04O2 (NCM) cathode materials were two-dimensionally visualized on a micro-scale gathering by nano-scale analysis, which enabled high-resolution particle analysis, through transmission electron microscopy coupled with X-ray energy dispersive spectroscopy. Degraded (capacity retention

In this study, we report an accurate and more reliable approach to estimate the dipole orientation of emitters especially phosphorescence, fluorescence and even thermally activated delayed fluorescence. The dipole orientation measurements are performed by examining the variation of the photoluminescence (PL) exciton decay rate from time-resolved PL and optical analysis. Our anisotropic dipole orientation results are consistent with those of previous reports. The studied measurement approach is very reliable and accurate to estimate the dipole orientation of any organic semiconductor materials regardless of whether they are doped or neat films.

We describe for the first time molecular rearrangements in a highly stable and porous Ni-rich layered oxide cathode material (LiNi0.80Co0.15Mn0.05O2, Ni-rich NCM) using a thermally reactive, Co-embedded metal–organic framework (MOF). The thermal decomposition of the MOF on the surface of the active material forms a molecular-level thin layer of CoOx species, which are thought to act as seeds for the dramatic transformation of the surface of the Ni-rich NCM from a layered oxide (Rm) to a more stable spinel-like phase (Fdm) before cycling and the formation of multi-scale (nano-to-micro) pores in the active particles. These phase transformations and morphology changes are associated with a galvanic replacement reaction between Co ions from the MOF and Ni ions near the surface of Ni-rich NCM, where some of the Ni ions migrate to the neighboring vacant Li sites by the diffusion of Co ions through melted residual lithium. Therefore, the resultant Co-/Ni-rich surface domains with a more stable spinel-like phase as well as a porous microstructure improve the cyclability and thermal stability of the MOF-inspired Ni-rich NCM.

Biofilm formation by Vibrio cholerae facilitates environmental persistence, and hyperinfectivity within the host. Biofilm formation is regulated by 3’,5’-cyclic diguanylate (c-di-GMP) and requires production of the type IV mannose-sensitive hemagglutinin (MSHA) pilus. Here, we show that the MSHA pilus is a dynamic extendable and retractable system, and its activity is directly controlled by c-di-GMP. The interaction between c-di-GMP and the ATPase MshE promotes pilus extension, whereas low levels of c-di-GMP correlate with enhanced retraction. Loss of retraction facilitated by the ATPase PilT increases near-surface roaming motility, and impairs initial surface attachment. However, prolonged retraction upon surface attachment results in reduced MSHA-mediated surface anchoring and increased levels of detachment. Our results indicate that c-di-GMP directly controls MshE activity, thus regulating MSHA pilus extension and retraction dynamics, and modulating V. cholerae surface attachment and colonization., Biofilm formation by Vibrio cholerae is regulated by c-di-GMP and requires the type IV MSHA pilus. Here, Floyd et al. show that the MSHA pilus is a dynamic system, and that both extension and retraction are directly controlled by c-di-GMP via regulation of activity of the extension ATPase MshE.

Highly efficient single-stack hybrid cool white organic light-emitting diodes (OLEDs) having blue-yellow-blue multiple emitting layers (EMLs) are designed and constructed by utilizing blue thermally activated delayed fluorescent (TADF) and yellow phosphorescent emitters. The out-coupling efficiencies of yellow and blue emissions are maximized by tuning the ITO and total device thickness that satisfies both of antinode positions for yellow and blue emissions in a limited multiple EML thickness. To obtain a cool white emission, the exciton formation ratio in the blue-yellow-blue multiple EML system is controlled by manipulating the recombination zone through charge conductivity variation of host medium in the blue TADF EML. The resulting device exhibits cool white emission with very high maximum external quantum efficiency of 23.1% and CIE color coordinates of (0.324, 0.337). We anticipate that the studied approach will raise the viability of single-stack hybrid cool white OLEDs for high performance display applications.

Mechanochemically coating over-lithiated layered oxide with the multi-functional VOPO4 is studied by using that VOPO4 is capable of accommodating lithium ions that are reversibly inserted/extracted at 3.8 V vs. Li/Li+ and exerts a surface-stabilizing effect. The impregnation with VOPO4 relieves the characteristic irreversible problems of over-lithiated layered oxide, since the initial fully delithiated structure of VOPO4 provides extra lithium storage sites and thus compensates for the unavoidable loss of irreversible charging capacity of VOPO4 during the first cycle. Interestingly, VOPO4 loadings below 1 wt. % improves cycleability, whereas higher loadings result in unfavorable kinetic hindrance. Additionally, VOPO4-coated samples exhibit enhanced thermal stability due to featuring reduced decomposition exothermicity and increase thermal runaway onset temperature.

L-lactic acid, as a monomer of polylactic acid, has attracted much attention because of the growing market for biodegradable bioplastics to reduce landfill waste. As an industrial L-lactic acid producer, Saccharomyces cerevisiae is generally used because it survives in low pH. However, in S. cerevisiae, production of L-lactic acid causes a decrease in intracellular pH, which leads to slow glycolytic flux, and consequently results in a lower productivity of L-lactic acid. For this reason, yeast strains that maintain their growth and the activities of metabolic enzymes during lactic acid production need to be developed for industrial applications. Herein, acid stable enzymes from acidophilic archaea Picrophilus torridus were expressed in L-lactic acid producing S. cerevisiae to increase glycolytic flux at low intracellular pH conditions for a higher L-lactic acid titer. Enzymes of lower glycolysis including phosphoglycerate kinase, phosphoglycerate mutase, enolase, and pyruvate kinase from P. torridus were introduced to develop a novel L-lactic acid producing strain. It was clearly shown that the production of lactic acid in the developed strain increased by 20% compared to the parental strain. To the best of our knowledge, this is the first report of P. torridus enzymes used in metabolic engineering to enhance the metabolic flux at a lower intracellular pH. Moreover, it is expected that the new strain will have an enhanced glycolytic flux at a low pH expressing acid stable enzymes that could be used to produce other valuable organic acids with increased titers.

In this study, a new type of test equipment is proposed to verify the performance of yaw brakes. A Nacelle, one of the wind turbine unit, rotates every 15 minutes to adjust its position to perpendicular to the blowing wind, which is known for yawing motion. The nacelle contains a main shaft, a gear box, and a generator, so that the size and weight are huge. A yaw brake system is the main device to stop the rotating nacelle during the yawing motion. A big disc of which the diameter is about 2 meters and several brakes are installed at the bottom part of the nacelle. Due to the difficulty of the size, the performance test for the yaw brake is very difficult. New tester is designed using a partial disk to simulate the disk brakes in the nacelle, as well as the application of braking force by a hydraulic actuator located at double the radius of the disk in order to reduce the hydraulic power. The stresses and strains are calculated through CAE analysis, and the values are compared with those from strain gage tests. After verifying the performance of the tester and testing two kinds of brake pads, it is found that alumina and chromite increase the friction coefficients but produce vibration and sound noise.

In this paper, we report two new phenanthroline-based compounds, 1,4-bis(2-phenyl-1,10-phenanthrolin-4-yl)benzene (p-bPPhenB) and 1,3-bis(2-phenyl-1,10-phenanthrolin-4-yl)benzene (m-bPPhenB), for the charge generation unit of tandem organic light-emitting diodes (OLEDs). These two compounds exhibited high electron mobility of (5.8–4.4) × 10–3 cm2/(V s), a very small injection barrier at the p–n junction interface, a high glass transition temperature of 123.9–182.1 °C, and exceptionally good operational stability. Because of such excellent characteristics, a single-stack red phosphorescent OLED (PhOLED) with p-bPPhenB showed a low driving voltage (2.7 V) and significantly improved maximum power efficiency (56.8 lm/W), external quantum efficiency (30.8%), and device lifetime (LT95, 130 h) compared to those of the control device using bathophenanthroline (Bphen) (3.7 V, 39 lm/W, 27.1%, and 13 h). Furthermore, a two-stack (tandem) red PhOLED using p-bPPhenB in the charge generation unit exhibited superior cha...

Spinel-embedded lithium-rich oxides are synthesized and their structural phases are analyzed. The type of spinel LiM0.5Mn1.5O4 (M = Ni, Co, Mn) embedded is varied by controlling the spinel composition and content. Of the various composites fabricated with different spinel phases, the LiCo0.5Mn1.5O4-embedded over-lithiated layered oxide (OLO) shows the best electrochemical performance as a cathode because of the absence of a parasitic phase and its high structural stability. The formation energy of the LiCo0.5Mn1.5O4-embedded oxide is determined through first-principles calculations and is found to be lower than that of the pristine oxide as well as other spinel-phase-embedded oxides. It is also observed that use of OLO with optimal embedded spinel LiCo0.5Mn1.5O4 in a cylindrical 18650-type cell results in improvement in the full-cell electrochemical performance.