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To replace the noble metals used in hydrodeoxygenation (HDO) catalysts, guaiacol HDO was conducted using various transition metal-loaded catalysts. Co/TiO2 was highly active for guaiacol HDO, enabling a more economic removal of the methoxy groups compared to the Ru/TiO2 catalyst, resulting in superior cyclohexanol selectivity. When a WO3 promoter was added to the Co catalyst to enhance its oxygen removal ability, the conversion of guaiacol was severely reduced because the co-impregnated WOx species decreased the number of exposed Co sites. To avoid this phenomenon, Co and WO3 were isolated by physically mixing Co/TiO2 and WO3/TiO2, where 100% conversion and oxygen removal could be achieved under 10 bar H2 at 250 °C. The cause of the catalyst deactivation was systematically investigated by magnetic separation of the physical mixture of the catalysts after the reaction, followed by a series of characterization studies. Temperature-programmed-oxidation mass spectroscopy and Raman spectroscopy revealed that the deposition of carbonaceous species was the main contributor to the deactivation of WO3/TiO2, and the catalytic activity could be successfully recovered by simple calcination at 400 °C. This study provides insights into the development of economical and efficient physically mixed HDO catalysts using transition metals, and contributes to the understanding of the deactivation and regeneration of physically mixed HDO catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • HCl treatment was applied to Ga-based MFI samples that possess distinct Ga species. • The extent of Ga removal was based on the strength of Ga-zeolite interaction. • Appropriate removal of Ga led to an increase in propane aromatization performance. • HCl treatment following hydrothermal synthesis reliably yielded superior catalysts. The identification of various Ga species in Ga-zeolites plays a crucial role in the development of appropriate catalysts because catalytic performance depends significantly on the state of Ga. This proves to be challenging, however, because of the limited pool of conventional characterization techniques, and the diversity of chemically possible Ga conformations. Here, through investigation on three characteristic Ga-zeolites with distinct states of Ga, we demonstrate that qualitative information on the nature of Ga in these catalysts could be derived by a facile HCl treatment, based on the ability of HCl to preferably eliminate the Ga species that share weaker interaction with the zeolite. Furthermore, the treatment was able to successfully tailor the Ga species in certain Ga-zeolites by selectively retaining the most desirable species for propane activation, leading to a considerable enhancement in propane aromatization performance. [ABSTRACT FROM AUTHOR]

Basal-like breast cancer (BLBC) has a clinically aggressive nature. It is prevalent in young women and is known to often relapse rapidly. To date, the molecular mechanisms regarding the aggressiveness of BLBC have not been fully understood. In the present study, mechanisms of aggressiveness of BLBC involving EGFR and/or HER2 expression and interactions between tumor and tumor-associated macrophages (TAMs) were explored. The prognosis of breast cancer patients who underwent surgery at Samsung Medical Center was analyzed. It was found that the co-expression of EGFR and HER2 was associated with a worse prognosis. Therefore, we generated EGFR-positive BLBC cells with stable HER2 overexpression and analyzed the profile of secretory cytokines. Chemokine (C-C motif) ligand 2 (CCL2) expression was increased in HER2-overexpressed BLBC cells. Recombinant human CCL2 treatment augmented the motility of TAMs. In addition, the conditioned culture media of HER2-overexpressed BLBC cells increased the motility of TAMs. Furthermore, activation of TAMs by CCL2 or the conditioned culture media of HER2-overexpressed cells resulted in the production of pro-inflammatory cytokines, such as IL-8 and IL-1β. These observations reveal that CCL2 derived from EGFR and HER2 co-expressed BLBC cells can lead to increased TAM recruitment and the induction of IL-8 and IL-1β from recruited TAMs, triggering the tumorigenesis of breast cancer with the expression of both EGFR and HER2. Our findings demonstrate that EGFR+ and HER2+ BLBC aggressiveness is partially mediated through the interaction between BLBC and TAMs recruited by CCL2. [ABSTRACT FROM AUTHOR]

The nanocomposite for the Li-ion battery anode was fabricated with SiO 2 , poly(aniline-co-anthranilic acid) (PAAA), and the functionalized multiwall carbon-nanotube (fMWCNT). The successful formation of cross-link and hydrogen bonds among SiO 2 , PAAA, and fMWCNT in the nanocomposite were confirmed. The electrostatic-spray deposition was applied for the direct preparation of the nanocomposite electrode on the current collector in order to achieve high uniformity and mechanical stability of the electrode. The nanocomposite electrode prepared by electrostatic-spray mitigated the volume expansion of SiO 2 during battery operation, which resulted in the excellent battery performance compared with that by the conventional slurry-casting method. The nanocomposite electrode revealed high initial discharge capacity (1415 mAh/g), capacity retention (1231 mAh/g at the 500th cycle), and rate capability (∼45 % capacity at 3 A/g vs. that at 0.1 A/g). We believe the entangled nanocomposite electrode is the promising electrode structure that can be used for the next-generation battery systems. [Display omitted] • Silica based nanocomposite electrode with cross-linked structure was synthesized. • Encapsulation of silica by PAAA polymer results in mechanical stability. • Further cross-linking with fMWCNT improves lithium-ion and electron transport. • Electrostatic-spray method showed superior performance in compare to slurry casting. • High energy storage capability (1231 mAh/g) was achieved after 500 cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrogen spillover enhanced the metal efficiency of Ru in guaiacol hydrogenation. • Liquid phase hydrogen spillover was activated as the Ru dispersion decreased. • Inert TiO 2 could act as active sites when mixed with spillover-active catalysts. • Dilution effect was not observed for the catalysts with highly dispersed Ru. • Hydrogen spillover in the liquid phase can be activated in the absence of water. Decrease in the metal dispersion of noble-metal-loaded catalysts with high metal loading is a major factor reducing noble-metal efficiency. Herein, we investigated the enhancement in metal efficiency of Ru/TiO 2 catalyst by utilizing hydrogen spillover in the liquid-phase. Ru was highly dispersed at low loadings (0.1 and 0.5 wt%), while larger nanoparticles were formed at higher loadings (1–5 wt%). The hydrogen spillover in liquid phase was activated at reaction temperature (100 °C) as the Ru dispersion decreased, which was confirmed through physical dilution experiments, hydrogen temperature-programmed-reduction, and kinetic analysis. Isotope experiment was conducted using D 2 O, observing inverse kinetic isotope effect (IKIE) for the high-Ru-loading catalysts. Based on the understanding of the hydrogen spillover in the liquid phase, the low metal efficiency of high-Ru-loading catalysts resulting from low dispersion could be compensated simply by physically mixing pristine TiO 2 , which played a role as new active sites when liquid-phase hydrogen spillover was activated. [ABSTRACT FROM AUTHOR]

The proactive safety seat (PSS) is a recently developed active safety system for securing occupant safety in out-of-seat position (OOSP), which was applied in the Hyundai Genesis G80 in 2020. However, there has not been sufficient quantifiable verification supporting the effectiveness of the PSS. The present study was performed to determine the effectiveness of the PSS for occupant safety in OOSP and to identify areas for additional improvement. Six test conditions were considered to determine the effectiveness of the PSS for augmentation of occupant safety in OOSP. Ten healthy men participated in the tests. Compared with the no PSS condition, maximum head excursion and neck rotation were significantly decreased in the PSS condition by 0.6–0.8-fold and 0.6–0.7-fold, respectively (P < 0.05). The PSS condition in which the seat pan was moved forward to the mid position showed a greater effect in reducing the characteristic motions related to submarining, compared with the condition in which the seat pan was moved rearward to the mid position (P < 0.05). These results suggested that PSS augments occupant safety in OOSP. This study provides valuable insights in ameliorating risks to the occupant in unintended seat positions before braking and/or collision. [ABSTRACT FROM AUTHOR]

Shared mobility is a service that allows users to share various transportation modes and use them with reservations when necessary. It started with private automotive car-sharing and ride-sharing services. Currently, it operates on a wider range, including personal mobility devices such as electric bicycles and scooters. The purpose of this study is to derive a direction for providing future shared mobility services through analysis of factors affecting the usage intention of both current and prospective users. The survey targets 753 citizens living in Gyeonggi Province, Korea. The survey period is from February 12, 2020, to February 26, 2020. In this study, a logistic regression analysis is conducted to investigate the factors affecting the use intention of shared mobility. The analysis results show that gender, car ownership, and education, among variables reflecting socio-demographic characteristics, have significant effects on intention to use shared mobility. Moreover, we find that experience factors, including mainly used transportation modes, ownership of shared mobility device, past experience in similar services, satisfaction of existing shared mobility services, and distance from the home to the nearest bus stop, are also statistically influential. The analysis results are expected to lay the foundation for the introduction of shared mobility services and can be used as data for planning smart mobility services in the future. [ABSTRACT FROM AUTHOR]

Cluster of differentiation 133 (CD133) is a transmembrane glycoprotein that has been reported as a marker of cancer stem cells or cancer‐initiating cells in various cancers. However, its contribution to tumorigenesis and differentiation remains to be elucidated. To determine the role of CD133 in colon cancer, we silenced CD133 in human colon cancer cells. Silencing of CD133 results in decreased cell proliferation, survival, migration, invasion, and glucose transport. These effects are mediated by downregulation of the human epidermal growth factor receptor 3 (HER3)/Akt/mTOR signaling pathway, culminating in reduced expression of the glucose transporter GLUT1. We also confirm that the cellular phenotypes of CD133‐silenced cells are mediated by GLUT1 downregulation. We conclude that CD133 is a potential tumor initiator that positively regulates GLUT1 expression through modulation of HER3/Akt/mTOR signaling. [ABSTRACT FROM AUTHOR]

Phthalates are mainly used as binders and plasticizers in various industrial products including detergents, surfactants, waxes, paints, pharmaceuticals, food products, and cosmetics. However, they have been reported to be endocrine disruptors, which are chemicals that can mimic or disturb endocrines, causing interference to the endocrine system. Recently, there have been numerous reports showing that phthalates have negative health impacts such as asthma, breast cancer, obesity, type II diabetes, and male infertility. Due to these effects, there is an urgent need for phthalate alternatives. In this study, the potential cytotoxicity of phthalates and their substitutes were screened in HaCaT cells, a human keratinocyte cell line, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) thiazolyl blue assay, immunocytochemistry, flow cytometric analysis, and western blotting. We confirmed that common phthalates such as butyl benzyl phthalate (BBP), di-n-butyl phthalate (DBP), and di-2-ethylhexyl phthalate (DEHP) have genotoxic effects, leading to cell death. Among the known phthalate substitutes, tributyl O-acetylcitrate (ATBC), triethyl 2-acetylcitrate (ATEC), and trihexyl O-acetylcitrate (ATHC) were tested for cytotoxicity. As a result, ATEC showed similar levels of cytotoxicity with the phthalates whereas ATBC and ATHC did not show significant cytotoxicity even in high doses (5 mg/ml). • Phthalates cause DNA damage and apoptosis in human keratinocyte cells. • Triethyl 2-acetylcitrate caused a similar rate of cytotoxicity with the phthalates. • Phthalates and phthalate alternatives increased DNA methylation levels. [ABSTRACT FROM AUTHOR]

Titanium dioxide nanoparticles, due to their smaller size and increased surface area comparted to the bulk form, are known to be bioreactive and have unexpected toxicological outcomes. Previous studies have shown that nanoscale titanium dioxide induces reactive oxygen species (ROS)-mediated cytotoxicity and genotoxicity. Although many reports have discussed the ROS-mediated cytotoxic effects of titanium dioxide nanoparticles (TiO2-NPs), their effects on the receptor–ligand association are unknown. In this study, the possibility that TiO2-NPs can interfere with the receptor–ligand binding was assessed by monitoring alterations in the phosphorylation status of proteins downstream of the epidermal growth factor receptor (EGFR) signaling cascade. TiO2-NPs blocked ligand-induced EGFR autophosphorylation, leading to the deactivation of EGFR downstream effectors such as Akt and extracellular signal-regulated kinase signaling, inducing cell death. • Titanium dioxide nanoparticles induce apoptosis in breast cancer cells. • Titanium dioxide nanoparticles cause decreased cell proliferation and adhesion. • Titanium dioxide nanoparticles interfere with the EGFR signaling pathway. [ABSTRACT FROM AUTHOR]

We propose a new way of studying the spin content of a hadron by looking at its response in a rotating frame. By collecting all responses of quarks and gluons in a rotating frame, we describe the spin-rotation coupling of spin-1 quarkonia and thereby reveal their spin contents in a relativistic formalism. We demonstrate that both the perturbative and non-perturbative contributions in the operator product expansion follow a universal formula that identifies the spin-rotation coupling with unit strength. This allows us to recognize the total spin-1 of the vector and axial vector quarkonia in terms of the total angular momentum of quarks and gluons. Specifically, we find the spin contents of J / ψ , χ c 1 , ϒ (1 S) , and χ b 1 are slightly different from the naive quark model picture. For example, the J / ψ is traditionally considered as an S-wave particle, but we find quarks do not carry all of the total spin. [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation of bio-oil to obtain oxygen-free hydrocarbon at low-temperature remains a substantial challenge to produce economically feasible biomass-derived fuel. Among the various Ru-loaded catalysts, Ru/DT-51, a sulfate-containing anatase TiO 2 , showed prominent oxygen removal attributed to the sulfur content of the catalysts. The introduction of sulfur on Ru/TiO 2 resulted in lower conversion of guaiacol, although the degree of oxygen removal obtained at 100% conversion was significantly enhanced, with 50% even at mild reaction temperature of 100 °C. The introduction of sulfur modified the distribution of exposed Ru species by selectively covering Ru in the form of sulfide, which was confirmed through X-ray photoelectron spectroscopy (XPS), CO chemisorption, CO diffuse reflectance infrared Fourier transform (CO-DRIFT), and temperature-programmed-desorption of ammonia coupled with a mass detector (NH 3 -TPD-MS). By introducing sulfur to Ru/TiO 2 , the product selectivity in guaiacol HDO was regulated to enhance the oxygen removal even at a low temperature of 100 °C. [Display omitted] • Liquid phase guaiacol HDO was conducted at 100 °C. • Aliphatic oxygenates cannot be further deoxygenated at applied reaction conditions. • Sulfur-doping on Ru/TiO 2 significantly enhanced the oxygen removal. • S-doping modified the distribution of exposed Ru species. [ABSTRACT FROM AUTHOR]

Nonylphenol polyethoxylates (NPEOs) are a major group of nonionic surfactants widely used in various detergents, cleaners, plastics, papers, and agro-chemical products. Nonylphenol (NP), which is a final degraded metabolite derived from NPEOs, has been reported as an endocrine disrupter, known to mimic or disturb reproductive hormone functions. Concern about the hazards of NP and NPEOs has generated legal restrictions and action plans worldwide. Considering the fact that NP and NPEOs are majorly used in the production of products such as detergents, shampoos, and cosmetics which frequently come into contact with the skin, we investigated the effects of NP and NPEOs on a human keratinocyte cell line (HaCaT). In this study, the toxicity of NP and NPEOs was screened in HaCaT cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide thiazolyl blue assay and Western blotting. The potential cytotoxicity of substitutes was assessed by dose-response assays, relative cell viability, and genotoxicity caused by specific alterations in DNA damage response proteins (including ataxia-telangiectasia mutated, p53, Chk1, Chk2, and Histone H2A.X). We demonstrated that NP and NPEOs are toxic to HaCaT cells, as revealed by the decreased cell viability after 24 h treatment. NPs and NPEOs also induced apoptosis and DNA damage as shown by the activation of Poly(ADP-ribose) polymerase, Caspase-3, and Histone H2A.X. [ABSTRACT FROM AUTHOR]

Loss of runt‑related transcription factor 3 (RUNX3) has been reported in various cancers, and one of the mechanisms mediating loss of RUNX3 expression is DNA methylation. However, the role of RUNX3 expression and its DNA methylation status as prognostic factors in endometrial cancer remain unclear. In the present study, the expression and promoter methylation of RUNX3 was examined in endometrial cancer tissues and cell lines, as well as their association with endometrial cancer prognosis. Fifty‑five endometrial cancer tissues and two endometrial cancer cell lines (HEC1‑α and Ishikawa) were studied. RUNX3 expression and promoter methylation were examined using reverse transcription‑polymerase chain reaction (RT‑PCR), methylation specific PCR (MS‑PCR), and immunohistochemical staining. The demethylating agent 5‑aza‑2'‑deoxycytidine (ADC) was used to reverse the methylation of the RUNX3 promoter. Loss of RUNX3 expression was observed in 50.9% (27/53) of endometrial cancer tissues and in the HEC1‑α cell line by immunohistochemistry and RT‑PCR, respectively. Methylation of the RUNX3 promoter was observed in 62.2% (33/53) of endometrial cancer tissues, 12.5% (1/8) of normal endometrial tissues, and the HEC1‑α cell line by MS‑PCR. Tumor grade and stage were significantly correlated with loss of RUNX3 expression. The expression of RUNX3 was restored by treatment with ADC and resulted in growth inhibition in HEC1‑α cells. The present results suggested that methylation may serve a critical role in the silencing of RUNX3 and loss of RUNX3 expression may serve as a prognostic marker in endometrial cancer. [ABSTRACT FROM AUTHOR]

Egr-1 is known to function mainly as a tumor suppressor through direct regulation of multiple tumor suppressor genes. To determine the role of Egr-1 in breast tumors in vivo , we used mouse models of breast cancer induced by HER2/neu. We compared neu-overexpressing Egr-1 knockout mice (neu/Egr-1 KO) to neu-overexpressing Egr-1 wild type or heterozygote mice (neu/Egr-1 WT or neu/Egr-1 het) with regard to onset of tumor appearance and number of tumors per mouse. In addition, to examine the role of Egr-1 in vitro , we established neu/Egr-1 WT and KO tumor cell lines derived from breast tumors developed in each mouse. Egr-1 deletion delayed tumor development in vivo and decreased the rate of cell growth in vitro . These results suggest that Egr-1 plays an oncogenic role in HER2/neu-driven mammary tumorigenesis. [ABSTRACT FROM AUTHOR]

In this study, we propose doxorubicin (DOX) loaded oligonucleotides (ONTs) attached to gold nanoparticles (AuNPs) as a drug delivery system for cancer chemotherapy. DOX is one of the representative cancer chemotherapy agents and is widely used by many researchers as a chemotherapy agent in the drug delivery system. Due to the advantages of AuNPs such as simple steps in synthesis, high surface-area-to-volume ratio, and biocompatibility, we utilized AuNPs as drug delivery vehicle. AuNPs were synthesized by chemical reduction to be 13 nm diameter. The G-C rich oligonucleotides were used both for drug loading sites and AuNPs capping agents. 80% of DOX in solution could be bound to ONTs on AuNPs to became DOX-loaded AuNPs coated with ONTs (Doxorubicin-Oligomer-AuNP, DOA), and about 28% of loaded DOX was released from the as-prepared DOA. Confocal microscopy observation showed that DOA was well transported into cells, and finally the DOX was released into the cell nucleus. The drug's efficacies such as in vitro cytotoxicity and in vivo tumor growth inhibition were demonstrated with SW480 colon cancer cell line and a xenograft mouse model. MTT assay was performed to see the cytotoxicity effect on SW480 cells treated with DOA for 24 h, and the cell viability was determined to be 41.77% (p < 0.001). When DOA was administered regularly to a tumor bearing mouse, the tumor growth inhibition degree was examined by measuring the tumor size. The treatment-control (T/C) ratio was found to be 0.69. Thus, our results suggest the use of DOAs as promising drug delivery systems for colorectal cancer therapy. [ABSTRACT FROM AUTHOR]

Cancer cells require increased aerobic glycolysis to support rapid cell proliferation. For their increased energy demands, cancer cells express glucose transporter (Glut) proteins at a high level. Glut1 is associated with basal-like breast cancer and is considered a potential therapeutic target. To investigate the possibility of Glut1 as a therapeutic target in breast cancer cells, we downregulated Glut1 in triple-negative breast cancer (TNBC) cell lines using a short hairpin system. We determined whether Glut1 silencing might enhance anti-proliferative effect of chemotherapeutic agents. Contrary to our hypothesis, ablation of Glut1 attenuated apoptosis and increased drug resistance via upregulation of p -Akt/p-GSK-3β (Ser9)/β-catenin/survivin. These results indicated that the potential of Glut1 as a therapeutic target should be carefully reevaluated. [ABSTRACT FROM AUTHOR]

We calculate the Wilson coefficients of dimension 6 gluon operators with spin indices in the two point correlation function of the heavy scalar, pseudoscalar, and axialvector currents. Our result completes the list of all Wilson coefficients of gluon operators up to dimension 6 for the correlation functions between heavy quark currents without derivatives. We then use the result to investigate the stability of the QCD sum rule results for the η c , J / Ψ , χ c 0 , and χ c 1 mesons near T c . While the inclusion of the dimension 6 operators increases the stability of the sum rules for all currents, all of them break down slightly above T c with that for the J / ψ persisting to relatively highest temperature. [ABSTRACT FROM AUTHOR]

As an improvement of the QCD sum rule method to study modifications of light vector mesons in nuclear matter and/or at finite temperature, we calculate the Wilson coefficients of all independent gluonic non-scalar operators up to dimension 6 in the operator product expansion (OPE) of the vector channel for light quarks. To obtain the gluon part of the light quark OPE from the heavy quark one, we also compute the heavy quark expansion of the relevant quark condensates. Together with the results for the quark operators that are already available in the literature, this completes the OPE of the vector channel in a hot or dense medium for operators up to dimension 6. [ABSTRACT FROM AUTHOR]

Recently, cloud computing and cyber-physical system (CPS) are definitely basic elements in real industrial field. In particular, security is a mandatory factor for communications and operations in these environments. However, the existing CPS security mechanism is not suitable to the telecommunication framework provided by the standards. In addition, random number function of high entropy must be used to enhance security with encrypted communications and must support perfect secrecy. Random number functions supported by the devices instead of servers do not have sufficient entropy. Entropy injection and seed replacement are also impractical. In this paper, we propose a security scheme which provides light-weight secure CPS information transmission and device control scheme in integration of CPS and cloud computing. In this scheme, a light-weight security scheme can multicast event information to users who have heterogeneous device information access authorities based on oneM2M standards, and also be able to manage the control devices. This paper provides performance analysis of proposed scheme and confirms its security and efficiency. [ABSTRACT FROM AUTHOR]

Conventional electrodes for lithium ion batteries, represented as the electrode films casted on the metal foil, are struggling to fulfill the requirements for the flexible electronics due to their heavy, thick, rigid, and brittle structure, which can lead to the deterioration of electrical contact followed by low cycling stability under the repeating mechanical stress. Therefore, development of stable and flexible electrodes is of crucial demand for the implementation of lithium ion batteries to the flexible electronic devices. In this study we demonstrate that the flexible and light buckypaper with high electrical conductivity is the promising alternative to the metal current collectors. In addition, the high capacity anode based on SiO 2 nanoparticles is introduced to the functionalized buckypaper. Our electrode reveals high energy storage capability (1101 mAh/g) even after 300 cycles. The composite electrode can be considered the potential high-performance anode for flexible electronic devices. [Display omitted] • The flexible, light, and thin anode for the Li-ion battery was fabricated using the functionalized buckypaper. • SiO 2 nanoparticles were directly generated on the buckypaper to develop high performance anode with excellent flexibility. • The high capacity (1101 mAh/g) could be achieved after 300 cycles due to the functionalized buckypaper. [ABSTRACT FROM AUTHOR]

[Display omitted] • Improving Ru catalytic efficiency is key for sustainable biorefinery processes. • Ru is loaded on activated carbon and oxide supports such as SiO 2 , TiO 2 , and Al 2 O 3. • Catalytic liquid-phase hydrogenation of gluconic acid is examined. • Addition of activated carbon improves the turnover rate of Ru. • Atomic H spills over from the supported Ru catalyst to activated carbon. Improving the efficiency of heterogeneous catalytic reactions is essential for enhancing the production efficiency of highly sustainable biorefineries. As a feedstock of biorefineries, alginic acid, which is a major component of brown algae, is converted into high value-added sugar alcohols such as sorbitol via hydrolytic hydrogenation over a Ru-based heterogeneous catalyst. In this study, Ru catalysts loaded on various supports such as activated carbon (AC), SiO 2 , TiO 2 , and Al 2 O 3 were prepared and applied in the liquid-phase hydrogenation of gluconic acid – an intermediate in the hydrolytic hydrogenation of alginic acid. When AC was mixed as an additive with the oxide-supported Ru catalysts, the turnover rate of Ru in the hydrogenation of gluconic acid increased threefold, particularly for Ru/ SiO 2. According to various analyses, AC can uptake more spilt-over hydrogen from Ru and exhibit superior adsorption ability for reactants compared to other metal oxides, thereby providing additional catalytically active sites. The simple strategy of adding pristine AC resulted in significantly enhanced turnover rate of the oxide-supported Ru catalyst, which is a significant breakthrough for sustainable biorefinery processes. [ABSTRACT FROM AUTHOR]

A novel ethylenediamine derivative of a rhodamine 6G silica particle (RSSP) was covalently grafted onto the surface of mesoporous silica to create a fluorescent chemosensing hybrid material for the detection of Fe 3+ . The prepared RSSP was dispersed in water, and its optical sensing response to various metal cations (Ag + , Na + , Li + , K + , Cs + , Hg 2+ , Cu 2+ , Ca 2+ , Cd 2+ , Co 2+ , Fe 2+ , Mg 2+ , Ni 2+ , Pb 2+ , Zn 2+ , Fe 3+ and Al 3+ ) was evaluated through the resulting fluorescence spectra. Upon coordination with Fe 3+ , the promoted ring opening of the rhodamine spirolactam ring in the RSSP activated a fluorescence response via CHEF (chelation enhancement fluorescence). This fluorescence enhancement was induced by the spirolactam ring system of the chemosensor immobilized in the pore. Conversely, the fluorescence response of the RSSP–Fe 3+ complex was quenched by the addition of EDTA, which abstracted the Fe 3+ ion from the complex and turned the sensor off, confirming that the recognition process was reversible. The proposed chemosensor also exhibited excellent selectivity for Fe 3+ over competing environmentally relevant metal ions. The chemosensor can also be used over a wide pH range and was readily regenerated. The sensing ability of RSSP makes it desirable for practical applications in microfluidics analysis tools, intracellular bio-imaging and lab-on-a-chip development. [ABSTRACT FROM AUTHOR]

We identify the independent dimension 6 twist 4 gluon operators and calculate their renormalization in the pure gauge theory. By constructing the renormalization group invariant combinations, we find the scale invariant condensates that can be estimated in nonperturbative calculations and used in QCD sum rules for heavy quark systems in medium. [ABSTRACT FROM AUTHOR]

The design and development of fluorescent chemosensors have recently been the focus of considerable attention for the sensitive and specific detection of environmentally and biologically relevant metal ions in aqueous solutions and in living cells. Herein, we report photophysical results for a 1 H -pyrrole-2-carboxaldehyde-substituted rhodamine 6G derivative (RCS) that possesses specific binding affinity toward Al 3+ and Cu 2+ at micromolar concentration levels. In an N , N -dimethylformamide (DMF) and water (v/v = 2/8) medium, the RCS chemosensor exhibits a substantially enhanced absorbance intensity at 532 nm and a color change from colorless to pink for Cu 2+ ; it also exhibits significant “off–on” fluorescence at 557 nm, accompanied by a color change from colorless to fluorescent-yellow upon binding to Al 3+ . The RCS sensor exhibits extremely high fluorescence enhancement upon complexation with Al 3+ , and it can be used as a “naked eye” sensor. Through fluorescence titration at 557 nm, we confirmed that RCS exhibits a fluorescence response with a remarkable enhancement in emission intensity resulting from the complexation between RCS and Al 3+ , whereas no emission appeared in the case of competitive metal ions (Cu 2+ , Al 3+ , Li + , Na + , K + , Cs + , Mg 2+ , Ca 2+ , Fe 2+ , Co 2+ , Ag + , Zn 2+ , Cd 2+ , Hg 2+ and Pb 2+ ) in a DMF and water (v/v = 2/8) solution. The reversible ring-opening mechanism of the rhodamine spirolactam induced by Al 3+ /Cu 2+ binding and the 1:1 stoichiometric structure between RCS and Al 3+ were adequately supported by Job-plot evaluation, optical titration and FT-IR analysis. The lowest detection limit for Al 3+ is 3.20 × 10 6 M −1 in a DMF and water (v/v = 2/8) solution. Al 3+ -induced chelation-enhanced fluorescence (CHEF) is associated with spirolactam ring opening of the rhodamine unit. Finally, RCS was successfully applied for the bio-imaging of Al 3+ in living HeLa cells and for fluorescence imaging of a microfluidic system. [ABSTRACT FROM AUTHOR]

A complete hydrodeoxygenation(HDO) of vanillin to yield cycloalkanes was performed using bifunctional Ru loaded HZSM-5 catalysts with different metal loadings (0.1, 0.5, 1, 3, and 5 wt%) and Si/Al 2 ratios (Si/Al 2 = 23,300) in n-octane/water biphasic system. Both the reaction pathway and product distribution were influenced by the metal/acid balance of the catalysts. Higher metal/acid ratio promoted C aryl -C cleavage reaction, resulting in the increased yield of cyclohexane. Synergetic effect of metal and acid sites was observed in the bifunctional catalyst, attaining as high as 40-fold increase of metal efficiency in the ring hydrogenation reaction, compared to lone metal site catalyst. The effect of solvent composition was evaluated, revealing that the presence of water promoted the overall HDO reaction. By balancing metal/acid and introducing appropriate solvent system, efficient catalytic system that minimized carbon loss and improved metal efficiency for vanillin HDO was obtained. [Display omitted] • HDO of vanillin as a model reaction of upgrading biowaste-derived bio-oil. • Reaction pathway of the complete HDO of vanillin to cycloalkane elucidated. • Metal acid balance within Ru/HZSM-5 catalyst determined the reaction pathway. • Synergetic effect of metal and acid was observed in the bifunctional catalyst. • Presence of water promoted the overall HDO reaction. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two step synthesis of pyrylium-squaraine dye, in which the first step synthesis is of pyrylium, salt and second step is condensation with squaric acid. [•] SQ dye can be used to determine Hg2+ ion with high selectivity. [•] The selective binding of Hg2+ leads to a visible color change in bluish green to purple (with, excess Hg2+). [•] Selective binding leads to ∼150nm [697nm–840nm] bathochromic shift. [•] Mode of binding site was confirmed by the 1H NMR titration method and FTIR studies. [ABSTRACT FROM AUTHOR]

To develop a wrist robotic exoskeleton-type interface (REI) for force interaction, it should have a suitable range of motion similar to human wrist activities of daily living, large torque output performance, and low moving parts inertia for dynamic motion response to cover the human behavior frequency. In this paper, a wrist REI based on a fully actuated coaxial spherical parallel mechanism (CSPM) is proposed to satisfy the aforementioned features. The fully actuated CSPM-based wrist REI (FC-WREI) has the characteristics of pure rotation similar to the human wrist, high torque output by parallel torque synthesis, and low moving parts inertia due to the base arrangement of the actuators. Due to the mechanical advantages and design optimization, the FC-WREI maximally provides torque as much as 56.49–130.43% of the maximum isometric torque of the human wrist, while providing a consistent range of motion to the human wrist without interference problem. Moreover, it is confirmed that the inertia of the FC-WREI is up to 5.35 times lower than similar devices. These advantages of the FC-WREI mean that the device is applicable to various fields of REIs for force interaction. [ABSTRACT FROM AUTHOR]

One of the organic dye materials which has long been investigated is regarded as rhodamine 6G dye class. This dye material shows a special attractive intention with considerable interests due to the reason of its promising photochemical properties such as clear photoabsorption and emission characteristics. In this study, a novel fluorescent dye compound based on rhodamine 6G derivative was designed and synthesised through the reaction of rhodamine 6G hydrazide and indole-3-carboxaldehdyde. The resulting absorption and fluorescent emission spectra of this chemosensor were determined on the properties of sensing function towards Hg2+. This chemosensor1was also investigated on the binding ratio between chemosensor1towards Hg2+using Job's method. Related electron density and energy state of the dye compound were also characterised by computational calculations. [ABSTRACT FROM PUBLISHER]

Rhodamine dyes have been attracted to many researchers due to its excellent photophysical properties. Interesting one of these dyes is rhodamine 6G. In this study, we have designed and synthesized a strong yellowish-green fluorescent emission dye sensor based rhodamine 6G for the detection of Hg2+ ions. It has noticeable properties of application for detecting and recognizing the presence of Hg2+ ions. In this regard, the optical properties of this dye sensor were intensively investigated using UV-Vis absorption, fluorescent spectrophotometer. Formation type of metal binding complex for this dye sensor was also determined by Job's plot method. Finally, computational calculation was simulated and calculated to approach for HOMO/LUMO of this dye sensor. [ABSTRACT FROM PUBLISHER]

One-pot conversion of alginic acid, which was derived from brown algae, to furfural was investigated using various solid acid catalysts. Among the solid acid catalysts tested, Amberlyst-15 showed the highest activity in furfural production in aqueous media. When the effect of reaction media was examined by applying various organic solvent mixtures, it was found that γ-butyrolactone/water co-solvent system was selected as the most appropriate system for the reaction. Maximum furfural yield of 32.2% was obtained using Amberlyst-15 in the γ-butyrolactone/H 2 O at 210 °C for 20 min. Catalyst showed gradual deactivation behavior as the reaction proceeded, although the catalyst recovered its activity upon the simple treatment with sulfuric acid. N 2 adsorption-desorption experiments, Fourier-transform infrared spectroscopy (FT-IR), back titration, and CHNS analysis were applied to investigate the physicochemical property of post-reaction samples, confirming that the leaching of the active sulfonic acid group and decrease in acid density was the major cause of deactivation. • Various solid acid catalysts were used in alginic acid conversion into furfural. • GBL/H 2 O was the most appropriate co-solvent among the solvents tested. • Maximum furfural yield of 32.2% was obtained. • Leaching of active site and decrease in acid density caused deactivation. • Used catalysts were regenerated with simple treatment with sulfuric acid. [ABSTRACT FROM AUTHOR]

The dispersion relation of the ϕ meson in nuclear matter is studied in a QCD sum rule approach. In a dense medium, longitudinal and transverse modes of vector particles can have independently modified dispersion relations due to broken Lorentz invariance. Employing the full set of independent operators and corresponding Wilson coefficients up to operator dimension-6, the ϕ meson QCD sum rules are analyzed with changing densities and momenta. The non-trivial momentum dependence of the ϕ meson mass is found to have opposite signs for the longitudinal and transverse modes. Specifically, the mass is reduced by 5 MeV for the longitudinal mode, while its increase amounts to 7 MeV for the transverse mode, both at a momentum scale of 1 GeV. In an experiment which does not distinguish between longitudinal and transverse polarizations, this could in principle be seen as two separated peaks at large momenta. Taking however broadening effects into account, the momentum dependence will most likely be seen as a small but positive effective mass shift and an increased effective width for non-zero momenta. [ABSTRACT FROM AUTHOR]

• Ternary composite was fabricated to develop hybrid supercapacitor electrode. • The supercapacitor electrode consists of epoxide functionalized buckypaper, polypyrrole and silver nanoparticles. • Chemical interactions are introduced among individual components in the electrode. • Both higher electrical conductivity and charge transfer efficiency are ascribed to chemical interactions in the electrode. • The chemically interconnected supercapacitor delivers high energy density. In this study, a chemically interconnected composite, called EBP-PPY-AgNP, was fabricated to develop high-performance hybrid supercapacitor electrodes. The composite consists of epoxide-functionalized buckypaer (EBP), polypyrrole (PPY), and silver nanoparticles (AgNP). The structure was characterized using Raman spectroscopy, X-ray photon spectroscopy (XPS), and scanning electron microscopy (SEM). Also, cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) analyses were conducted to estimate the electrochemical performance. The results were more excellent than those of the other electrodes not chemically interconnected. Finally, the energy density was calculated, and the value was higher than in previous studies that examined electrodes with similar materials. [ABSTRACT FROM AUTHOR]

In this work, the CeO 2 @polypyrrole (CeO 2 @PPy) core-shell nanosphere has been synthesized via an ultra-sonication method and they are utilized for the photo-reduction of hazardous Cr6+ to benign Cr3+. • Novel CeO 2 @PPy core-shell nanosphere were successfully synthesized via ultrasonic-assisted method. • The CeO 2 @PPy showed active visible light photocatalytic activity towards hazardous Cr6+. • The CeO 2 @PPy core-shell nanosphere improved the charge separation and electron transfer efficiency. • The CeO 2 @PPy photocatalysts possess excellent photostability and reusability. In this work, the CeO 2 @polypyrrole (CeO 2 @PPy) core-shell nanosphere has been synthesized via an ultra-sonication method using bath type (WUC-D22H, Daihan Scientific, Korea) and they are utilized for the photo-reduction of hazardous Cr6+ to benign Cr3+. The ultrasonic frequency and power were 20 kHz and 100 W, respectively. The PPy shielded CeO 2 in aqueous solution could prevent the dissolution of CeO 2 and to improve the photocatalytic ability of CeO 2. X-ray diffraction was used to confirm the crystalline structure of as prepared CeO 2 @PPy core-shell and FT-IR was used to identify the functional groups. The uniform sized core of PPy and shell of CeO 2 were observed by transition electron microscopy. The ultrasonic assisted synthesized CeO 2 @PPy core-shell exhibits a narrow bandgap (UV-DRS) and good reduction efficiency with higher reusability and stability compared to pure CeO 2 , PPy and mechanical mixing of CeO 2 @PPy. Moreover, the synergistic effect of CeO 2 and PPy core-shell structure facilitate a higher electron transfer rate and prolong lifetime of photogenerated electron-hole pairs which can achieve good reduction rate of 98.6% within 30 min. In particular, the pH, catalyst, and Cr6+ concentration effects were optimized in photocatalytic reduction reactions. Meanwhile, this photocatalysis with fast and effective electron transfer mechanism for the Cr6+ reduction was elucidated. This method opens a new window for simple fabrication of conducting polymers-based metal oxide nanocomposite towards wastewater remediation and beyond. [ABSTRACT FROM AUTHOR]

Ruthenium on N-doped mesoporous carbon successfully hydrogenated alginic acid into sorbitol and mannitol, suppressing byproduct formation with excellent hydrothermal stability. • Alginic acid was selectively hydrogenated into sorbitol and mannitol over Ruthenium on N-doped mesoporous carbon. • The intimate interaction between Ru and N-doped carbon support was observed by H 2 -TPD. • Oxidized Ru species suppressed side reactions such as epimerization and C-C cleavage. • The intimate interaction might be the reason for the inhibition of leaching and aggregation of Ru. • The highest yield of sorbitol and mannitol was obtained as 50.3% over Ru(5)/NMC(0.1)(600). Ruthenium supported on nitrogen-doped mesorporous carbons (NMC) catalyzed hydrolytic hydrogenation of alginic acid to produce C6 sugar alcohols, mainly sorbitol and mannitol. Nitrogen contents were controlled by changing the weight ratio of urea/glucose and carbonization temperature. The highest yield of target C6 sugar alcohols was 50.3% (sorbitol: 24.3% and mannitol: 26.0%) at 180 °C for 1 h over Ru(5)/NMC(0.1)(600), where 0.1 and 600 were the urea/glucose ratio and carbonization temperature (°C), respectively. The intimate interaction between Ru and the support induced by nitrogen doping resulted in suppression of byproduct formation such as C4-C5 sugar alcohols and galactitol. Moreover, the interaction as evidenced by various analytical techniques resulted in the excellent durability of the catalyst after repeated reactions without severe leaching or aggregation of Ru. [ABSTRACT FROM AUTHOR]

• Macroalgae-derived alginic acid was hydrogenated into sorbitol and mannitol over RuCu bimetallic carbon catalyst. • Addition of Cu to Ru/carbon catalyst resulted in coverage of active Ru surface and electron transfer between Ru and Cu. • Formation of RuCu bimetallic clusters with the intimate interaction between Ru and Cu might improve the catalytic activity. • The highest yield of sorbitol and mannitol was obtained as 47.4% over Ru(5)Cu(1)/AC-N-13 at 180 °C for 2 h. The objective of this study was to investigate the effect of Cu addition to carbon supported Ru catalysts on the hydrogenation of macroalgae-derived alginic acid into sugar alcohols, mainly sorbitol and mannitol. Both geometric and electronic effects were determined based on results of H 2 -TPR, H 2 - or CO-chemisorption, and XPS analyses after Cu was added to Ru. The addition of Cu to Ru caused blocking of active Ru surface and electron transfer between Ru and Cu. The intimate interaction between Ru and Cu formed RuCu bimetallic clusters which expedited hydrogen spillover from Ru to Cu. The highest yield of target sugar alcohols of 47.4% was obtained when 5 wt% of Ru and 1 wt% of Cu supported on nitric acid-treated activated carbon reacted at 180 °C for 2 h. The RuCu bimetallic catalyst exhibited deactivation upon repeated reactions due to the carbon deposition on the catalyst. [ABSTRACT FROM AUTHOR]

Camptothecin (CPT) and its derivatives are the only chemical class that targets the enzymatic activity of DNA topoisomerase I, which is involved in DNA damage and subsequent cell apoptosis. Despite CPT's advantages, its use has been restricted due to extremely poor solubility, drug resistance by several efflux pumps, short half‐life, and poor bioavailability. To overcome these limitations, we designed and synthesized a water‐soluble CPT‐conjugated molecular transporter that successfully and rapidly delivered CPT into cells. The conjugate had affinity toward mitochondria inside cells and it was distributed mainly to kidney, lung, and spleen. MTT assay confirmed that the CPP‐conjugate decreased cell viability of colon cancer cell lines to a much greater extent than the parent drug. This novel approach has the potential of improving CPT efficacy for future in vivo applications, especially for colon cancer therapy. [ABSTRACT FROM AUTHOR]

Bisphenol-A (BPA) was first synthesized in the 1890s and has been used in many plastic products. However, BPA is known to act as an endocrine disruptor and has been found to be toxic to human health. Many alternative substances have been developed to replace BPA, but it is still widely used worldwide. In this study, we identified the potential cytotoxicity of BPA by evaluating toxicity using human keratinocytes. Also, we evaluated cytotoxicity of BPA substitutes to determine their suitability as an alternative to BPA. The proliferation assay using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, flow cytometry and western blot analysis showed that BPA significantly affect cell viability, induction of apoptotic fraction and increased activation of DNA-damage marker protein. In addition, through the same experiments, the substitutes of BPA were shown to be significantly less toxic than BPA, and the least toxicity was observed with 1,4-cyclohexanedimethanol (CHDM) and terephthalic acid (TPA). In conclusion, this study suggests that cytotoxicity of BPA induces apoptosis of human keratinocytes, and that CHDM and TPA are the most suitable substitutes for BPA. [ABSTRACT FROM AUTHOR]

The transportation-disadvantaged population is rapidly increasing through aging; moreover, the mobility of the elderly has increased due to life expectancy improvements and lifestyle changes. To respond to these changes, a customized mobility service specifically tailored to the travel patterns of the elderly was developed in this study. In particular, an autonomous shuttle service that can improve the operational efficiency and the accessibility of existing transportation methods was proposed by considering the travel characteristics of elderly people, who mainly travel short distances. To this end, a study was conducted in Seongnam City, Republic of Korea, where mobility support services for the elderly are insufficient. Using smart card data, the elderly were classified according to their travel patterns, with autonomous shuttle routes suggested for each travel purpose. We derived four clusters via the Gaussian mixture model clustering, with travel purposes classified according to the spatiotemporal travel patterns. Finally, the major routes for each travel purpose were selected, and feasible road paths for autonomous shuttle operation were suggested using the concept of ODD (operational design domain). This holistic methodology is expected to contribute to the development of autonomous mobility services for the elderly and for the establishment of welfare policies based on the smart card data. [ABSTRACT FROM AUTHOR]

Bifunctional zeolite-based catalysts often require high degree of interaction between the active metal and zeolite. Here, we propose a 'top-down' synthesis method for the preparation of Ga/ZSM-5, where a substantial amount of Ga is initially loaded and partially removed afterwards by acid treatment with HCl solution of different concentrations. Characterization results reveal that among the various Ga species originally created, the HCl treatment selectively eliminates the redundant Ga species on the zeolite surface, while causing minimal impact on the zeolite structure. The post-treated sample, left with Ga species located in the zeolite pores and strongly interacting with the zeolite, was successfully applied in propane aromatization; the sample treated with 0.2 M HCl showed an initial benzene, toluene, and xylene yield of 43.7%, which was nearly 1.5 times higher than that of the Ga-impregnated sample prepared without such procedure, containing an identical Ga loading. [Display omitted] • Post HCl-treatment was applied to Ga/ZSM-5 containing excess loading of Ga. • HCl treatment selectively removed Ga species weakly interacting with the zeolite. • Minimal amount of well-dispersed Ga was present on post HCl-treated Ga/ZSM-5. • Post HCl-treated Ga/ZSM-5 displayed superior propane aromatization performance. [ABSTRACT FROM AUTHOR]

This study aims to develop a spatiotemporal traffic density estimation method based on the advanced driver assistance system (ADAS) Probe data. This study uses the vehicle trajectory data collected from the ADAS equipped on the sample probe vehicles. Such vehicle trajectory data are used firstly to estimate the distance headway between the vehicles on a specific road section, and the postprocessed distance headway data are finally used to estimate the spatiotemporal traffic density. The innovation aspect of the proposed methodology in this study is that traffic density can be estimated in high accuracy only with a small size of data points in support of ADAS. On the other hand, existing density estimation method requires a large number of probe vehicles and its numerous data sets including either the global positioning system data or the dedicated short-range communication data. To verify the proposed methodology, a two-step evaluation is performed: the first step is a numerical evaluation that estimates the spatiotemporal traffic density based on the simulated vehicle trajectory data, and the second step is an empirical evaluation that estimates the density based on the real-road data in both peak and nonpeak periods. Beyond the methodology development, this study verified the estimation reliability of traffic density under various traffic conditions based on the sampling rate of ADAS-equipped vehicles. Consequently, the traffic density estimation error decreased as the sampling rate increased. Estimation accuracy of 90% or higher was observed in all scenarios when the sampling rate was 50% or higher. It indicates that fairly accurate traffic density estimation is feasible using probe vehicles that correspond to half of the vehicles driven on the road. Therefore, this practical approach is expected to mitigate the burden of density estimation, particularly in future road systems in which ADAS and autonomous vehicles are prevalent. [ABSTRACT FROM AUTHOR]

Deriving insights from the global production network (GPN) framework, we examine the recent development of the liquid crystal display (LCD) industry in South Korea. Using the GPN framework, we focus on the role of the national state as an active inter-scalar mediator in the dynamic strategic coupling process between global leading firms and local actors in globalizing regional development. We argue that the role of the national state as an inter-scalar mediator was crucial in coordinating localized growth factors with globalizing external factors to create and develop the LCD industry. This was achievable because of the legacy of the developmental state and the top-down implementation of policy in South Korea. Using the idea of the inter-scalar mediator, we specify the role of the state as a container of laws and practices and as a constructor of regional innovation systems to globalize regional development in the context of a centripetal society. A multi-strategy approach, which included one month of participatory observation, in-depth interviews and secondary data collection, was adopted in order to enhance the validity and reliability of the data. [ABSTRACT FROM PUBLISHER]

The seat comfort of automobiles is one of the significant factors for determining the driver's fatigue, emotional experience, and individual space (which captures their individuality, rather than just a means of transportation in modern society). Conventional automobile seats could not provide seating comfort suitable for all drivers, in the form of seats that fit each driver's body type and the difficulty of meeting individual needs. This study proposes self-shape adjustable (the SSA seats) seats that improve the sitting comfort, safety, and secure the stability, by adjusting shape fit to the driver's body type. The SSA seats transforms the seat itself, in a way that improves the distribution of contact pressure and reduces sitting fatigue, with the pneumatic system. The transformed seats provide better sitting comfort and safety than the conventional automobile seat, by providing a seat shape suitable for the body shape of all users. It was verified that the SSA seats, proposed in this paper, have a uniform and improved pressure distribution, compared to the conventional seat, in various sitting postures; the contact area between the seat and user is enlarged, and the pressure concentrated on the ischial bone is lowered. In addition, it was proven (through user evaluation) that quantitative evaluation verification was the same as qualitative evaluation results. [ABSTRACT FROM AUTHOR]

NOx emissions from various sources cause serious environmental problems and harm human health. The selective catalytic reduction of NOx by hydrogen (H 2 -SCR) using Pt/ZSM-5 catalysts has attracted significant attention due to its effective removal of NOx at low temperatures. However, Pt/ZSM-5 has a narrow operating window because of the excessive oxidation of NO to NO 2 at high temperatures. In this study, Pt/ZSM-5 catalysts were prepared by thermal aging treatment of fresh Pt/ZSM-5 at various temperatures to prevent the excessive oxidation of NO to NO 2 at high temperatures, and these catalysts were applied to the H 2 -SCR reaction. The fresh Pt/ZSM-5 catalyst showed high NOx conversion at low temperatures, reaching 93% at 75 °C. However, the conversion rapidly declined as the temperature increased, dropping to 50% at 200 °C. In contrast, when the catalyst was thermally aged, the NOx conversion increased at all temperatures, and the operating window was significantly widened. Especially, Pt/ZSM-5 aged at 850 °C, maintained 84% NOx conversion even at 200 °C. Various characterizations, including XRD, NH 3 -TPD, STEM, CO-DRIFTS, and probe reactions revealed that the oxidation ability of the thermally aged catalysts decreased due to the sintering of Pt, resulting in widen operating windows. This study provides insights into the development of Pt-based catalysts for H 2 -SCR applications that can improve NOx reduction efficiency over a wide temperature range. [Display omitted] • Pt/ZSM-5 was thermally aged at various temperatures and applied to H 2 -SCR reaction. • Thermally aged catalysts maintain high de-NOx capability at high temperatures. • Sintering and oxidation of Pt particles were observed in thermally aged catalysts. • Thermally aged catalysts have lower oxidation ability and reduced NO 2 production at high temperatures. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effect of each component on shale gas aromatization over Mo/ZSM-5 was examined. • Ethane and propane promote the formation of benzene over naphthalene. • Methane delays the formation of hard coke and increases catalytic stability. • Mathematical approach based on atomic balance determines synergy between reactants. • Ethane and propane partially hinder methane conversion to aromatics. The chemical inertness of methane is a significant bottleneck for its direct conversion into value-added light aromatics. However, co-feeding higher hydrocarbons with methane produces intermediates that facilitate the participation of methane in aromatization. This synergistic effect has typically been observed under conditions that do not allow the conversion of methane without any co-reactants (over non-Mo-based catalysts at temperatures below 650 ℃). Therefore, the interaction between methane and higher hydrocarbons remains unexplored under conditions that allow methane activation. In this study, we explored the behavior of co-reactants in the direct aromatization of simulated shale gas (a mixture of methane, ethane, and propane) over Mo/ZSM-5. Our aim was to comprehend the complex co-aromatization system under conditions optimized for rigorous activation of methane, which leads to a considerable production of aromatics. The majority of reaction indices in the shale gas aromatization system were governed by the presence of ethane and propane, which were represented by a rapid catalytic lifetime cycle. Mathematical calculations, based on experimentally derived C and H balances, revealed an unexpected anti-synergy within the components of shale gas where the conversion of methane to aromatics was partially suppressed by the presence of ethane and propane. These findings expand the understanding of the complex yet desirable shale gas aromatization system, and also highlight the need for the development of new catalysts capable of further enhancing the activity of methane among the reactants. [ABSTRACT FROM AUTHOR]

[Display omitted] • A highly active Pd/NH 2 -CNT catalyst for formic acid dehydrogenation was prepared. • A combination of Cit and APTES enables the formation of ultrasmall Pd particles. • Amine functional groups from APTES capture H+ from HCOOH to increase HCOO– • A regeneration process is required to use the catalyst repeatedly. Formic acid is a promising hydrogen source and liquid organic hydrogen carrier because of its high hydrogen density. To produce hydrogen from formic acid, catalytic dehydrogenation of formic acid over Pd-based catalysts has been investigated. Here, a highly active catalyst is rationally designed. Carbon nanotubes without micropores were adopted as a support to facilitate the mass transport of reactants or products. Pd particles were made as small as possible to provide a large number of active sites and to alleviate the activation barrier for hydrogen desorption. Amine functional groups were introduced into carbon nanotubes to generate formate anions by capturing protons from formic acid. Based on this design, ultrafine Pd nanoparticles (1.76 nm) on amine-functionalized carbon nanotubes were successfully synthesized. This catalyst demonstrated remarkable activity for the formic acid dehydrogenation reaction, with a high turnover frequency value of 2560 h−1 at 30 °C. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pd/zeolite catalysts are prepared using an ion-exchange followed by reduction method. • As-prepared Pd/ZSM-5 showed low activity and selectivity in hydrogenation reactions. • A controlled NaOH treatment promoted mesopore formation around the Pd nanoparticles. • A controlled NaOH treatment removed the Brønsted acid sites of the zeolite structure. • NaOH-treated Pd/ZSM-5 catalyzed the hydrogenation reactions without side reactions. Zeolites have been widely applied as support materials for metal nanoparticles. However, when developing a metal/zeolite catalyst for hydrogenation reactions, the Brønsted acid sites of zeolites can promote side reactions and the zeolite structure can inhibit the access of reactants to the metal, resulting in low activity and selectivity. In this study, these challenges are addressed by preparing a metal/zeolite catalyst via a modified ion-exchange followed by reduction method, and subjecting the catalysts to two test reactions, hydrogenation of vanillin and fatty acid methyl esters (FAMEs). After forming Pd nanoparticles within ZSM-5, it was treated with a NaOH solution in a controlled manner to form mesopores around Pd and replace hydronium ions with sodium ions to remove Brønsted acid sites. Pd/ZSM-5 catalysts prepared with controlled NaOH treatment showed higher hydrogenation reactivity and improved selectivity toward the desired hydrogenation products than those prepared without NaOH treatment. This study presents a simple strategy to prepare metal/zeolite catalysts to promote hydrogenation without side reactions. [ABSTRACT FROM AUTHOR]

The Korean government has announced plans to supply electrified buses to achieve decarbonization in the transportation sector and to create next-generation growth engines. Although a multitude of technical and political studies have been conducted to support the successful introduction of electrified buses, studies on the attitudes and perceptions of passengers toward electrified buses remain insufficient. To evaluate the perceptions and preferences of potential passengers toward the specific attributes of electrified buses, this study performed an online survey (N = 586) that includes people who had experienced travel on public buses. Values of the relative importance of eight different attributes—safety, ride comfort, environmental friendliness, exterior design, cleanliness, crowding, seat comfort, and convenience getting on/off—were evaluated using the best-worst scaling method. The results showed that safety (share of preference: 41.3%) was the most important attribute when using electrified buses. This was followed by eco-friendliness (14.3%) and ride comfort (13.6%). On the other hand, the least important attribute was exterior design (1.8%). Gender differences were also observed in the valuation of certain attributes among the passenger preferences toward electrified buses. The results of this study contribute to the development of strategies for the wide-spread adoption of electrified buses and provide a stepping-stone to a more sustainable public transportation system. [ABSTRACT FROM AUTHOR]

Uniform α-MnO 2 nanorods were synthesized via hydrothermal followed by ultra-sonication method. They exhibited high efficient catalytic conversion of refractory pollutant, methylene blue. • α-MnO 2 nanorods were synthesized via a simple hydrothermal followed by ultrasonication method. • α-MnO 2 nanorods exhibit excellent catalytic conversions toward refractory pollutant, methylene blue. • 99.7% was achieved for the catalytic conversion efficiency. • The nanorods showed better reusability and improved catalytic cycling stability. In this work, uniform α-MnO 2 nanorods were synthesized via a simple hydrothermal followed by ultrasonication method using ultrasonic bath (20 kHz, 100 W) without using any surfactant and template. The crystallographic phases and surface morphology were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transition electron microscopy (TEM) analysis, respectively. Functional group identification and chemical states of α-MnO 2 nanorods were confirmed by Fourier-transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The as-synthesized uniform nanorods of α-MnO 2 exhibit excellent catalytic conversion of toxic organic contaminant (methylene blue (MB)) in the presence of NaBH 4 as reductant. The α-MnO 2 exhibits excellent stability up to four repeated catalytic cycles with nearly 92% conversion. The kinetic rate constant (k), and turnover frequency (TOF) were 0.736 min−1 and 0.02 mmol mg−1 min−1, respectively. In addition, the fast electron transfer mechanism were investigated and discussed. These results open a new avenue for developing various metal oxide catalysts, which are expected to be very useful catalytic conversions. [ABSTRACT FROM AUTHOR]