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In this study, a large-area N-doped graphene film (NG/NF) was fabricated on a nickel foam (NF) substrate via thermal chemical vapor deposition along with the flow of gaseous C2H4/NH3 mixtures.

Toward the development of an energy-efficient artificial neuron device, a study of the mechanism of electroforming in OTS and mitigation of the electroforming by doping Sn in GeSe was conducted.

This file contains Supplemental figures, tables, and legends that accompany the main figures, as indicated in each legend. There are 3 supplemental tables and 6 supplemental figures. Table S1. List of potential target of the GNS compounds that were profiled in Figure 1 of the main text. Table S2. Half-maximal inhibitor concentration of the EGFR inhibitors tested. Table S3. Blood-brain-barrier penetration of the GNS compounds as assessed by the indicated pharmacokinetic measurements. Figure S1. Structural modeling studies show the binding characteristics of the indicated EGFR inhibitors. Figure S2. The effects of each EGFR inhibitor in the cell lines expressing mutant or wild type EGFR. Figure S3. In vivo effects of the GNS compounds. Figure S4. In vivo anti-tumor effects of the GNS compounds. Figure S5. In vivo anti-tumor effects of the GNS compounds in intracranial EGFR-mutant lung cancer. Figure S6. In vivo anti-tumor effects of the indicated EGFR inhibitors in intracranial EGFR-mutant lung cancer.

The clinical utility of approved EGFR small-molecule kinase inhibitors is plagued both by toxicity against wild-type EGFR and by metastatic progression in the central nervous system, a disease sanctuary site. Here, we report the discovery and preclinical efficacy of GNS-1486 and GNS-1481, two novel small-molecule EGFR kinase inhibitors that are selective for T790M-mutant isoforms of EGFR. Both agents were effective in multiple mouse xenograft models of human lung adenocarcinoma (T790M-positive or -negative), exhibiting less activity against wild-type EGFR than existing approved EGFR kinase inhibitors (including osimertinib). In addition, GNS-1486 showed superior potency against intracranial metastasis of EGFR-mutant lung adenocarcinoma. Our results offer a preclinical proof of concept for new EGFR kinase inhibitors with the potential to improve therapeutic index and efficacy against brain metastases in patients. Cancer Res; 77(5); 1200–11. ©2017 AACR.

Owing to the surge in plastic waste generated during the COVID-19 pandemic, concern regarding microplastic pollution in aqueous environments is increasing. Since sub-micron plastics can accumulate in the human body, their real-time detection in water is necessary. However, the decrease in the scattering cross-section of small polystyrene (PS) particles in aqueous media precludes detection by bright-field microscopy. To address this problem, we propose and demonstrate a differential interference contrast (DIC) system that incorporates a magnification-enhancing system to detect PS beads in aqueous samples. To detect micron-scale and sub-micron-scale PS beads in the stationary and mobile phases, a microfluidic chip was designed considering the imaging depth of focus and flow resistance. PS beads of various sizes flowing in deionized and tap water at varying speeds were quantitatively observed under Static and Flow conditions. The real-time detection and quantification of PS beads of size ≥ 200 nm at a constant flow rate in water was successful. It was also possible to classify two different sizes, 2 µm and 750 nm, in a mixed solution. Thus, the proposed novel method can significantly reduce the analysis time and improve the size-detection limit. The proposed DIC microscopy system can be coupled with Raman or IR spectroscopy in future study for chemical composition analysis.

The prediction of M-shaped δ-ferrite content along the thickness direction of continuously cast 304 austenitic stainless steel slab was performed using a diffusion-controlled phase transformation module of Thermo-Calc software. The surface and center of the slab, which solidified with different cooling rates and secondary dendrite arm spacing, were used for kinetic calculations. Comparison between observations and calculations for slab specimens demonstrated that the moving-boundary model could predict retained δ-ferrite content according to various thermal histories. After this validation, the effects of different cooling rates at liquid and solid-state were analyzed to understand the importance of each stage on the diffusion-controlled δ $$\to \gamma$$ phase transformation. Decrease in solid-state cooling rate generally had a larger effect on the reduction of δ-ferrite during cooling when the solidification rate was fast (27.75 °C/s) than when it was slow (0.075 °C/s). This model can be used to predict and control δ-ferrite behavior under different thermal histories during slab casting and welding practices.

We investigate the influence of constituent phases on the hydrogen-induced mechanical degradation in two ultra-high strength sheet steels. In the complex phase (CP) steel, of which microstructure can be regarded as monolithic in terms of hydrogen behaviors, the rate of hydrogen uptake gradually decreases with the charging time, while the transformation-induced plasticity (TRIP) steel exhibits a persistent hydrogen absorption up to the charging time of 48 h, which is attributed to the presence of austenite. The mechanical degradation of TRIP steel goes beyond that of the CP steel at charging time over 12 h, coincident with the condition in which the austenite contributes to the hydrogen uptake. Both the ultra-high strength and the presence of austenite have unfavorable influence on the hydrogen embrittlement. Therefore, in the TRIP steel, it is necessary to evaluate quantitatively the critical hydrogen concentration over which more care should be taken to reduce the risk of hydrogen-induced mechanical degradation.

The development of three-dimensional electrode substrates is a strategy for designing powerful electrolysis cells for hydrogen production combined with electrochemical oxidation of various refractory organic compounds. Herein, to achieve highly effective and low-cost anodic treatment of pollutants and simultaneous cathodic hydrogen evolution in a single electrolysis cell containing sulfate-laden wastewater, we fabricated carbon-coated TiC nanoarrays (C@TiC NAs) as efficient three-dimensional (3D) electroactive supports. The anodes prepared via the deposition of boron-doped diamond (BDD) on 3D C@TiC NAs (BDD@TiC NAs) exhibited 1.9-fold higher efficiency for benzoic acid degradation and 4.4-fold higher peroxydisulfate (PDS) generation than the conventional plate type BDD electrode. Moreover, with multi-activity assessment using 8 organic substances, the BDD@TiC NAs enabled successful anodic treatment of all tested refractory organics and the kinetic rate did not depend on the substrate type. For the cathode, Pt nano-dots (NDs) coated on C@TiC NAs (Pt@C@TiC NAs) can be simply prepared via salt coating and subsequent thermal reduction. Uniformly decorated Pt NDs with a low mass loading of 0.029 mg cm−2 on C@TiC NAs showed the same hydrogen evolution reaction performance as that of a commercial Pt plate. When a single electrolysis cell was configured using BDD@TiC NAs and Pt@C@TiC NAs, the cell performance surpassed that of a conventional ideal electrolysis cell (flat BDD//Pt plate) in all efficiency aspects: degradation of benzoic acid, sulfate radical generation, and hydrogen production.

This study investigated the performance of organic pollutant degradation using the electro-Fenton process and low-cost titanium (Ti) electrodes as cathodes. Three Ti electrodes with different morphologies, i.e., a plate and two meshes with large (MS-L) and small (MS-S) opening sizes, were evaluated using electrochemical characterization, as well as kinetic and energy studies based on the COD removal performance of the electro-Fenton process. The preliminary results indicated that the MS-S electrode, which has the largest electrochemically active surface area and lowest resistance amongst the three electrodes, could reduce Fe3+ to Fe2+ most effectively in the synthetic solution. However, when treating real wastewater, MS-L rather than MS-S exhibited 13.8% higher COD removal efficiency with a 1.5-fold higher rate constant (i.e., 0.0362 min−1) during the initial 30 min of the electro-Fenton process. This unexpected anomaly was due to excessive clogging by suspended solids (SS) present in the real wastewater that were easily captured by the narrow openings of MS-S. Consequently, a pilot-scale electro-Fenton system was operated using MS-L. The pilot experiment demonstrated stable degradation of organic pollutants for five consecutive months with an average COD removal efficiency of 86%, showing its feasibility in treating real wastewater. With its competitive regeneration of Fe2+, low manufacturing cost and energy consumption, the electro-Fenton process using Ti mesh with large opening sizes appears to be a viable and practical technology for wastewater treatment.

Inspired by information processing in biological systems, sensor-combined edge-computing systems attract attention requesting artificial sensory neurons as essential ingredients. Here, we introduce a simple and versatile structure of artificial sensory neurons based on a novel three-terminal Ovonic threshold switch (3T-OTS), which features an electrically controllable threshold voltage (

The fate and transport of microplastics (MPs) during deep bed filtration were investigated using combined laboratory experiments and numerical modeling. A series of column experiments were conducted within the designated ranges of six operating parameters (i.e., size of the MP and collector, seepage velocity, porosity, temperature, and ionic strength). A variance-based sensitivity analysis, the Fourier amplitude sensitivity test, was conducted to determine the priority in affecting both the attachment coefficient at the pore scale, and the subsequent stabilized height of the breakthrough curve at the continuum scale, which follows non-monotonic trends with singularity in the size of MP (i.e., 1 µm). Finally, Damkohler numbers were introduced to analyze the dominant mechanisms (e.g., attachment, detachment, or straining) in the coupled hydro-chemical process. The robustness of conceptual frameworks bridges the gap between pore-scale interactions and the explicit MPs removal in the continuum scale, which could support decision-making in determining the priority of parameters to retain MPs during deep bed filtration.

This study scrutinized the roles of sulfate radicals (SO4 −) and peroxydisulfate (PDS) formed from SO42− in electrochemical organic oxidation on a boron-doped diamond (BDD) electrode. The substrate-specific performance of electrochemical oxidation using SO42− as the electrolyte aligned with the reactivity of SO4 − produced via radiolysis- or heat-induced PDS activation, but was distinct from the non-selective oxidation efficiency observed in an aqueous ClO4− solution. A comparison of the treatment efficiencies using different electrolytes (i.e., Cl−, SO42−, and ClO4−) showed no pronounced enhancing effect of SO4 − on the anodic oxidation of diverse organics (except perfluorooctanoate), which implied that direct electron transfer and hydroxyl radical-induced oxidation proceeded as complementary reaction routes. Repeated electrolytic oxidation caused substantial electrolyte exchange from Cl− to ClO4−, which retarded organic oxidation accompanied by ClO4− accumulation. Conversely, high-yield PDS production observed when SO42− was used instead barely reduced treatment efficiency. Together with SO4 − detection in the electron paramagnetic resonance spectrum, a correlation between 4-chlorophenol oxidation rate and the faradaic efficiency for SO42− formation, monitored in PDS solutions while varying the cathode material, suggested cathodic PDS activation. The electrocatalytic performance was demonstrated to be further improved with anodically formed PDS activation through naturally occurring resistive heating or combination with UV photolysis as a post-treatment step.

To overcome the conventional limitation of TiO2 disinfection being ineffective under light-free conditions, TiO2 nanowire films (TNWs) were prepared and applied to bacterial disinfection under dark and UV illumination. TNW exhibited much higher antibacterial efficiencies against Escherichia coli (E. coli) under dark and UV illumination conditions compared to TiO2 nanoparticle film (TNP) which was almost inactive in the dark, highlighting the additional contribution of the physical interaction between bacterial membrane and NWs. Such a physical contact-based antibacterial activity was related to the NW geometry such as diameter, length, and density. The combined role of physical puncture and photocatalytic action in the mechanism underlying higher bactericidal effect of TNW was systematically examined by TEM, SEM, FTIR, XPS, and potassium ion release analyses. Moreover, TNW revealed antimicrobial activities in a broad spectrum of microorganisms including Staphylococcus aureus and MS2 bacteriophage, antibiofilm properties, and good material stability. Overall, we expect that the free-standing and antimicrobial TNW is a promising agent for water disinfection and biomedical applications in the dark and/or UV illumination.

Dimensionally stable RuO2 (RO)- and IrO2-based anodes have been widely used for electrochemical water treatment but alternative materials are required due to their well-recognized drawbacks such as high-cost and low oxygen evolution potential. In an effort to minimize noble metal contents, we herein fabricated electrospun Sb-doped SnO2 (ATO)/RO composite nanofibers as new anode materials by controlling precursor ratios. These composite nanofiber anodes have one-dimensional nanostructure assembled with highly uniform ATO and RO nanoparticles and their oxygen evolution potential was successfully tailored by compositional change. The ATO/RO nanofiber anodes, even with a small amount of RO of 3% exhibited superior electrocatalytic performance in oxidative organic degradation; complete degradation of bisphenol A as a model substrate was achieved during 20 min-electrolysis on ATO/RO anodes at a low current density of 3 mA⋅cm−2. This strategy provides the optimization of oxygen evolution reaction and current efficiency, resulting in excellent capability for electrochemical water treatment.

Singlet oxygen produced by irradiating photosensitizers (PSs) can be used to kill pathogens during water treatment. Chemical immobilization of the PSs on surfaces can maintain their disinfection function long-term. In this study, two model PSs (rose bengal (RB) and hematoporphyrin (HP)) were immobilized on a glass surface using a silane coupling agent with an epoxide group, and their antibacterial properties were analyzed. Fourier transform infrared spectroscopy demonstrated that a covalent bond formed between the epoxide group and hydroxyl group in the PSs. A large proportion of the immobilized PSs (approximately 50%) was active in singlet oxygen production, which was evidenced by a comparative analysis with free PSs. RB was more effective at producing singlet oxygen than HP. The immobilized PSs were durable in terms of repeated use. On the other hand, singlet oxygen produced by the PSs was effective at killing bacteria, mostly for Gram-positive bacteria (> 90% death for 2 h of irradiation), by damaging the cell membrane. The preferable antibacterial property against Gram-positive bacteria compared with that against Gram-negative bacteria suggested efficient penetrability of singlet oxygen across the cell membrane, which led to cell death. Taken together, it was concluded that immobilization of PSs on surfaces using the silane coupling agent proposed in this study was effective at killing Gram-positive bacteria by forming singlet oxygen.

This study comparatively examines the efficiency and mechanism of peroxymonosulfate (PMS) activation by twenty metal and metalloid nanoparticles loaded on alumina. Among the tested metals, Co exhibited the highest capacity for PMS activation and accompanying oxidative degradation of trichlorophenol (TCP), a representative organic pollutant in water. Other transition metals such as Mn, Cu, Mo, Ni, and W exhibited moderate activity, while Ti, Zn, Fe, V, Cr, Al, and Si were mostly ineffective. In contrast, all of the tested noble metals (Ru, Rh, Pd, Ir, Pt, and Au) except Ag enabled rapid PMS activation and TCP degradation, outperforming Co at acidic pH. Transition metals with noticeable PMS activation capacity differed from noble metals in several aspects, such as the effect of radical quenching on 4-chlorophenol (4-CP) degradation, electron paramagnetic resonance spectral features, oxidative conversion of bromide into bromate, and oxidation intermediate distribution. They were also distinguishable with respect to the dependence of PMS degradation on the presence of an electron donor (i.e., TCP), the capacity to activate peroxydisulfate (PDS), and the electrochemical response upon addition of PMS and 4-CP when fabricated into electrodes. Based on these observations, we categorized surface-loaded metal nanoparticles into two groups with distinctive PMS activation mechanisms: (i) transition metals such as Co, Cu, and Mo that activate PMS to produce highly reactive sulfate radicals (SO4 −); and (ii) noble metals such as Rh, Ir, and Au that mediated direct electron transfer from organic compound (electron donor) to persulfate (electron acceptor) without involving the formation of radical species.