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Organic Photovoltaics (OPVs) have emerged as leading materials for next-generation energy sources. Despite the advancements in organic photoactive materials, research on parallel tandem organic photovoltaics (PT-OPVs) has been limited. The efficiency of PT-OPVs can be improved by reducing the difference in the open-circuit voltages (V OC) between the front and back subcells. However, there is a significant gap in research on the middle transparent electrode (MTE), which is crucial for achieving the desired energy-level alignment between the photoactive layers of these subcells and establishing electrical connectivity between them. This gap limits the utilization of reported high-performance photoactive materials in PT-OPV devices. To address this issue, a novel MTE is developed by depositing a copper (I) thiocyanate (CuSCN) hole transport layer on a molybdenum oxide/thin silver/molybdenum oxide (MAM) multilayer structure. The MAM/CuSCN MTE is distinguished by its higher work function and reduced surface roughness. As a result, integrating the MAM/CuSCN MTE in the PT-OPVs substantially increases the V OC of the back subcells (from 714 mV to 773 mV) while simultaneously minimizing the difference in V OC between the front and back subcells; thus, improving the performance of the device. Our findings provide valuable insights into the engineering of MTEs to enhance PT-OPVs' efficiency. [Display omitted] • High-performance parallel tandem organic photovoltaics (PT-OPV) are fabricated. • Single-junction (opaque and semi-transparent) and PT-OPV devices are evaluated. • V OC disparity between the front subcell and back subcell is minimized. • MAM/CuSCN as middle TEs—higher work function & reduced surface roughness. [ABSTRACT FROM AUTHOR]

Heteroatom doping is useful for enhancing the electrochemical performance of sodium-based secondary battery (SBB) anodes. However, the complexity of synthesis and safety issues caused by harmful dopant precursors must be overcome. Herein, a one-step plasma-in-liquid process is adopted to synthesize N and S co-doped carbon-based anode material (NS/C) for SBBs. NS/C exhibits a large specific surface area (476.8 m2 g−1) and abundant active sites on its surface owing to its void structure. Owing to the advantages of this structure, NS/C evidently caused a co-intercalation reaction in an ether-based electrolyte while avoiding solid electrolyte interface (SEI) layer formation on the anode surface. Transmission electron microscopy, electrochemical impedance spectroscopy, cyclic voltammetry, and the Brunauer–Emmett–Teller method with a novel analysis method using terahertz waves are employed to prove that no SEI formed on the anode surface. When the anode is applied to a sodium-ion half-cell, NS/C exhibited a remarkable cycling life of 35,000 cycles at an ultrahigh current density of 100 A g−1 with high reversible capacity of >72 mAh g−1. Furthermore, NS/C shows outstanding electrochemical performance for a seawater battery anode, with a cycling life of more than 1500 at the first attempted current density of 10 A g−1. [Display omitted] • Plasma-synthesized N, S co-doped anode formed no SEI layer in an ether electrolyte. • THz wave analysis was used to identify absence of solid electrolyte interface layer. • N, S co-doped C-based anode showed high-rate capability in Na ion half-cell test. • N, S co-doped C-based anode improved performance of rechargeable seawater batteries. • N, S co-doped C is a prospective anodic material for Na-based secondary batteries. [ABSTRACT FROM AUTHOR]

In this study, a highly stable alginate/Fe 3 O 4 composite was synthesized, and systematically investigated for the practical application of strontium (Sr) removal in complex media, such as seawater and radioactive wastewater. To overcome the drawbacks of the use of alginate microspheres, high contents of alginic acid and Fe 3 O 4 were used to provide a more rigid structure with little swelling and facile separation, respectively. The synthesized composite was optimized for particle sizes of <400 μm and 1% content of Fe 3 O 4 . The alginate/Fe 3 O 4 composite showed excellent Sr uptake (≈400.0 mg/g) and exhibited outstanding selectivity for Sr among various cations (Na, Mg, Ca and K). However, in diluted Sr condition (50 mg/L), Ca significantly affected Sr adsorption, resulting in a decrease of K d value from 3.7 to 2.4 at the 0.01 M Ca. The alginate/Fe 3 O 4 composite could be completely regenerated using 0.1 M HCl and CaCl 2 . In real seawater spiked with 50 mg/L of Sr, the alginate/Fe 3 O 4 composite showed 12.5 mg/g of Sr uptake, despite the highly concentrated ions in seawater. The adsorption experiment for radio-active 90 Sr revealed a removal efficiency of 67% in real seawater, demonstrating the reliability of the alginate/Fe 3 O 4 composite. [ABSTRACT FROM AUTHOR]

Abstract: In this work, catalytic cracking of biomass waste oil fractions separated from food waste leachate was performed using microporous catalysts, such as HY, HZSM-5 and mesoporous Al-MCM-48. The experiments were carried out using pyrolysis gas chromatography/mass spectrometry (Py-GC/MS) to allow the direct analysis of the pyrolytic products. Most acidic components, especially oleic acid, contained in the food waste oil fractions were converted to valuable products, such as oxygenates, hydrocarbons and aromatics. High yields of hydrocarbons within the gasoline-range were obtained when microporous catalysts were used; whereas, the use of Al-MCM-48, which exhibits relatively weak acidity, resulted in high yields of oxygenated and diesel-range hydrocarbons. The HZSM-5 catalyst produced a higher amount of valuable mono aromatics due to its strong acidity and shape selectivity. Especially, the addition of gallium (Ga) to HZSM-5 significantly increased the aromatics content. [ABSTRACT FROM AUTHOR]

Abstract: Fast pyrolysis of Miscanthus was investigated in a bench-scale fluidized bed reactor for production of bio-oil. Process conditions were varied for temperature (350–550°C), particle size (0.3–1.3mm), feed rate and gas flow rate. Pyrolysis temperature was the most influential parameter upon the yield and properties of bio-oil. The highest bio-oil yield of 69.2wt.% was observed at a temperature of 450°C which corresponded to the end of the thermal composition of hemicellulose and cellulose. In the bio-oil, the water content was 34.5wt.%, and the main compounds in the organic fraction were phenolics and oxygenates. With increasing temperature, the amount of oxygenates in the bio-oil decreased gradually while that of water and aromatics increased rapidly. The bio-oil yield was not significantly affected by particle sizes or feed rates. The use of product gases as a fluidizing medium aided in increasing bio-oil yield. [Copyright &y& Elsevier]

Abstract: A single-walled carbon nanotube (SWCNT) thin plate was prepared using a smectic liquid crystal (Sm LC) template. The induced self-organizing SWCNT plate is attributed to π–π stacking between the hexagonal rings of the SWCNT wall and aromatic moieties in Sm LC. The SWCNT plate was characterized by Raman spectroscopy, scanning electron microscopy, X-ray diffraction and polarized optical microscopy. [Copyright &y& Elsevier]

Abstract: Verification of Pleurotus eryngii strains was assessed using ITS sequence analysis and RAPD fingerprinting. Sequence analysis of the ITS1–5.8S rDNA–ITS2 region of 24 strains of Pleurotus sp., which consisted of 22 strains of P. eryngii and the control strains P. ostreatus and P. ferulae, demonstrated that the DNA regions share mostly 99% sequence identity, indicating that sequence-based analysis is not applicable for the verification of closely related mushroom strains. To verify the mushroom strains using RAPD, we amplified DNA fragments from the total cellular DNA of 24 mushroom strains with 18 different random primers, yielding 538 distinct DNA fragments ranging from 200–4000bp. Analysis of the DNA fragment pattern showed that the 22 P. eryngii strains were clearly distinguished from the control strains P. ostreatus and P. ferulae, and could be categorized into five subgroups. Subsequent physiological studies on the development of fruiting bodies demonstrated the close correlation of the RAPD-based grouping with the phenotypical characteristics of mushroom fruiting bodies. [Copyright &y& Elsevier]

Abstract: Weakly acid to neutral CO2-rich springs (pH=5.5 to 6.7) with high concentrations of dissolved ions (TDS=419 to 3091 mg/L) and bicarbonate (249 to 2470 mg/L) occur in Kangwon district, South Korea. They are grouped into three chemical types: Na–HCO3, Ca–Na–HCO3, and Ca–HCO3. The Na–HCO3 type waters correspond to mature or partially equilibrated waters, while the other two types show the hydrochemical characteristics of immature waters. In this study, we examined the applicability of chemical geothermometers and multiple mineral equilibrium approach to estimate potential deep-reservoir temperatures. The application of silica, Na–K, and Na–K–Ca thermometers to a representative Na–HCO3 type water yielded a reasonable temperature estimate (115–157 °C) for a deep geothermal reservoir. The multiple mineral equilibrium approach yielded a similar temperature estimate (about 140–160 °C). On the other hand, the Ca–HCO3 type waters showed a relatively low and wide range of temperature estimates (about 60–130 °C), which suggests that their disequilibrium state is possibly due to surface water mixing. We believe that deep-reservoir temperatures of CO2-rich groundwaters in Kangwon district can be estimated from the chemistry of Na–HCO3 type waters and possibly approach 140–160 °C. [Copyright &y& Elsevier]

The use of surface-patterned lithium (Li) metal has been proposed as a promising strategy for inhibiting the formation of Li dendrites during repeated Li plating/stripping processes. Nevertheless, the conventional Li metal patterning process is complex, expensive, incompatible with mass production, and incapable of producing finely controlled patterns on the Li metal surface. A large, flexible patterning stamp capable of large-area patterns is developed using a silicon (Si) wafer-based chemical etching process, and its effect on the electrochemical performance of a Li metal anode is investigated. The newly developed stamps have 5,000% larger patterning area compared to the conventional stainless-steel stamps. Furthermore, when compared to conventional surface-patterned Li metal fabricated with conventional stainless-steel stamps (SP-LM), the surface-patterned Li metal fabricated with large and flexible patterning stamps (LAP-LM) demonstrates improved electrochemical performance and stable morphological properties. As a result, the LAP-LM is able to retain up to 85.2% of its initial discharge capacity (85.9 mAh g−1) after 200 cycles at 3C (3.96 mA cm−2), while the SP-LM shows a severe capacity decay after 150 cycles (94.0 mAh g−1 and 13.0 mAh g−1 at the 150th cycle and 200th cycle, respectively). [Display omitted] • A large, flexible patterning stamp capable of large-area patterns was developed. • The newly developed stamps achieved 5,000% larger patterning area for Li metal. • The new large-area stamp produced stable morphological properties for Li metal. • The new large-area stamp showed significantly improved electrochemical properties. [ABSTRACT FROM AUTHOR]

For locally advanced esophageal cancer, concurrent chemoradiotherapy (CRT) followed by surgery has been a standard treatment, while clinical studies showed comparable survival outcomes between definitive CRT and neoadjuvant CRT followed by surgery in patients responding to CRT. Thus, biomarkers are required to predict treatment outcomes and benefit of adding surgery after CRT. This prospective biomarker study examined the role of cell-free DNA (cfDNA) fragmentation profiles and genomic copy number variations (CNVs) in predicting treatment outcomes in esophageal squamous cell carcinoma patients treated with neoadjuvant or definitive CRT. The clinical response was evaluated after induction chemotherapy and after CRT. Fragment Ratio (FR)-score and I-score were calculated from plasma cfDNA reflecting fragment lengths and CNV of cfDNA, respectively. The association between indices of cfDNA (cfDNA concentration, FR-score, and I-score) and treatment outcomes (clinical response, time to progression [TTP], and overall survival [OS]) were evaluated. Sixty-one patients were included. Thirty patients received neoadjuvant CRT followed by surgery, whereas 31 received definitive CRT. Low baseline, post-induction chemotherapy, and post-CRT FR-scores and low post-induction I-score were significantly associated with improved treatment response (P < 0.05). Additionally, patients with surgery after CRT showed significantly longer survival than patients without surgery in the FR-score-high group (median TTP, 12.7 vs 3.4 months; P = 0.011; OS, not reached vs 12.9 months; P = 0.02), while there was no survival benefit with surgery in the FR-score-low group. FR-score may be a new biomarker to predict treatment response, residual tumor burden after CRT, and consequently, survival benefit of adding morbid surgery after CRT. FR-score has strength in a relatively simple and inexpensive methodology compared to deep sequencing, resulting in high availability and accessibility, despite limited sensitivity. [ABSTRACT FROM AUTHOR]

• PI polymeric binder creates a scaffold structure LiMP (Li metal powder)-based anode. • LiMP-based anode fabrication process using PI binder is economical and at easy. • PI polymeric binder forms a uniform protection layer on the limp-based anode. • Surface coating layer formed by PI binder deteriorates li dendrite formation. • A scaffold structure LiMP retains own structure deteriorating li dendrite formation. Effects of soluble polyimide (PI) binders on large-sized Li anodes (width = 21.5 cm; thickness = 40 μm) prepared using Li-metal powder (LiMP) have been investigated. PI binders form a uniform protective layer on exposed Li-powder-coated surfaces, thereby resulting in formation of scaffold-structured LiMP-based anodes. Uniform PI surface films favor realization of Li plating on Li-metal surfaces by forming a smooth surface structure, and the three-dimensional insulating PI matrix functions as a buffer layer that absorbs volume change. Moreover, PI binders facilitate enhanced cohesion between LiMP particles. The above-described triple action of PI binders significantly reduces Li dendrites. Consequently, PI-containing LiMP-based metal anodes demonstrate enhanced electrochemical performance compared to both polymeric binders and bare Li-metal foils. Results obtained in this study reveal that LiMP-based anodes containing PI binders exhibit 89% (98.2 mAh g–1) discharge-capacity retention during the 200th cycle, whereas bare Li-metal foil demonstrates sudden degeneration during the 65th cycle. Furthermore, PI containing LiMP-based anodes exhibit improved rate capability compared to other polymeric binders considered in this study. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Abstract: The amount of waste furniture generated in Korea was over 2.4 million tons in the past 3 years, which can be used for renewable energy or fuel feedstock production. Fast pyrolysis is available for thermo-chemical conversion of the waste wood mostly into bio-oil. In this work, fast pyrolysis of waste furniture sawdust was investigated under various reaction conditions (pyrolysis temperature, particle size, feed rate and flow rate of fluidizing medium) in a fluidized-bed reactor. The optimal pyrolysis temperature for increased yields of bio-oil was 450°C. Excessively smaller or larger feed size negatively affected the production of bio-oil. Higher flow and feeding rates were more effective for the production of bio-oil, but did not greatly affect the bio-oil yields within the tested ranges. The use of product gas as the fluidizing medium had a potential for increased bio-oil yields. [Copyright &y& Elsevier]

Abstract: Fast pyrolysis of sewage sludge was carried out under different reaction conditions, and its effects on bio-oil characteristics were studied. The effect of metal oxide catalysts on the removal of chlorine in the bio-oil was also investigated for four types of catalysts. The optimal pyrolysis temperature for bio-oil production was found to be 450°C, while much smaller and larger feed sizes adversely influenced production. Higher flow and feeding rates were more effective but did not greatly affect bio-oil yields. The use of the product gas as the fluidizing medium gave an increased bio-oil yield. Metal oxide catalysts (CaO and La2O3) contributed to a slight decrease in bio-oil yield and an increase in water content but were significantly effective in removal of chlorine from the bio-oil. The fixed catalyst bed system exhibited a higher removal rate than when metal oxide-supported alumina was used as the fluidized bed material. [Copyright &y& Elsevier]

• The regularity of copolyester (PBEAT) was designed for sustainable hot-melt adhesives. • The crystallinity, crystallization behavior, and open time were controlled by adjusting the copolyester's regularity. • Prepared hot-melt adhesives exhibited sufficient adhesion, excellent removability, and high biodegradability. Recent research has increased in eco-friendly hot-melt adhesives as alternatives to conventional commercial hot-melt adhesives. However, there have been limitations in terms of removability and biodegradability. This study addresses these issues by designing a novel molecular structure for a single polymer, resulting in a sustainable hot-melt adhesive that offers strong adhesion, clear removability, and high biodegradability without additional additives. By varying the ratio of alcohol monomers 1,4-butanediol (BD) and ethylene glycol (EG) during polymerization, we synthesized poly(butylene adipate-co-butylene terephthalate-co-ethylene adipate-co-ethylene terephthalate) (PBEAT) with four block segments. We increased the open time by reducing the regularity of the molecular structure, controlling crystallization behavior, and inhibiting polymer chain packing. This improvement in wettability with the adherend allowed us to achieve a lap shear adhesion strength of 3.18 MPa. Additionally, we proposed a debonding mechanism based on the correlation between the crystallization temperature (T c) block copolymer's and shear adhesion failure temperature (SAFT), demonstrating the removability of the prepared hot-melt adhesive. Finally, analyses of hydrolysis, enzymatic degradation, and biodegradation in compost confirmed that reduced crystallinity enhances biodegradability. PBE 30 AT, exhibiting the strongest adhesion strength, achieves complete degradation in compost within 20 days, faster than neat poly(butylene adipate-co-terephthalate) (PBAT). This research offers a novel and practical approach to enhancing the potential and expandability of sustainable adhesives by tailoring the molecular structure of the polymer. [ABSTRACT FROM AUTHOR]

The degradation of phenylacetate (PA) was investigated as a model to explore aromatic compound breakdown in the fungal system. Fungal strains capable of utilizing PA as their sole carbon source were isolated using a minimal solid medium supplemented with 0.5 % PA. Subsequent cultivation in minimum liquid medium revealed that selected fungal strains, including Trametes versicolor TV0876 and TV3295, Paecilomyces hepiali PH4477, and Akanthomyces muscarius AM1091, efficiently removed PA within 24 h. HPLC analysis of culture supernatants from various fungal strains revealed a time-dependent accumulation of 2-hydroxyphenylacetate (2-HPA) and 4-hydroxyphenylacetate (4-HPA), two key major metabolic products primarily found in ascomycetes and basidiomycetes, respectively. This suggests that the first hydroxylation of PA is catalyzed by two distinct hydroxylases, one for each fungal group. Furthermore, fungal species that make 4-HPA also produce phenylethanol (PE), indicating a distinct catabolic mechanism to remove PA by direct reduction of PA to PE. A. muscarius AM1091, identified as the most efficient PA degrader in this study, was studied further to determine the biochemical pathway of PA degradation. RNA-Seq and RT-PCR analyses of AM1091 revealed two oxidative enzyme genes, CYP1 and DIO4, upregulated in the presence of PA. Targeted disruption utilizing preassembled Cas9-gRNA ribonucleoprotein complexes and homologous DNAs harboring the URA3 gene as an auxotrophic marker resulted in the cyp1 and dio4 mutant strains. The cyp1 mutant was incapable of converting PA to 2-HPA, indicating its involvement in the C2 hydroxylation, whereas the dio4 mutant was unable to degrade 2,5-dihydroxyphenylacetate (2,5-DHPA), resulting in the accumulation of 2,5-DHPA. Our findings indicate that A. muscarius AM1091 degrades PA through the activities of CYP1 and DIO4 for the C2 hydroxylation and subsequent ring-opening reactions, respectively. • Phenylacetate (PA) degradation in fungi was initiated hydroxylation of aromatic ring. • Ascomycetes hydroxylated C2 of aromatic ring whereas basidiomycetes targeted C4. • A. muscarius degraded PA through the activities of PA 2-hydroxylase and homogentisate 1,2-dioxygenase. • Cas9-gRNA ribonucleoprotein complex generated deletion mutants of cyp1 and dio4 in A. muscarius. [ABSTRACT FROM AUTHOR]

Abstract: Threat of global warming and imminent exhaustion of fossil fuels call for development of alternative carbon-neutral energy sources. Among others, bio-oil, which can be produced from various biomass, can be used not only as an alternative fuel but also as a feedstock for production of high-value chemicals. In this study, the potential of wild reed growing in Suncheon Bay Ecological Park area as a bio-energy source was evaluated. Fast pyrolysis of reed for bio-oil production was carried out using a lab-scale reactor system. The effects of pyrolysis conditions were investigated. The produced gas, liquid and solid products were analyzed. The effect of carrier gas flow rate was shown to be not significant. The most important parameter determining the product yields was shown to be the reaction temperature in this study. The bio-oil yield was highest (52%) at 520 °C. The bio-oil yield was higher and the char yield was lower for a larger sample particle size, possibly due to the enhanced heat transfer to individual particles for larger particles packed loosely. The bio-oil was shown to be comprised of acids, alcohols, ketones, aldehydes, phenolics, aliphatic hydrocarbons, and aromatics, with phenolics and aromatics accounting for considerable fractions. The fast pyrolysis of reed is expected to be useful for obtaining valuable chemicals. [Copyright &y& Elsevier]

Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that modulates integrin and growth factor signaling pathways and is implicated in cancer cell migration, proliferation, and survival. Over the past decade various, FAK kinase, FERM, and FAT domain inhibitors have been reported and a few kinase domain inhibitors are under clinical consideration. However, few of them were identified as multikinase inhibitors. In kinase drug design selectivity is always a point of concern, to improve selectivity allosteric inhibitor development is the best choice. The current research utilized a pharmacophore modeling (PM) approach to identify novel allosteric inhibitors of FAK. The all-available allosteric inhibitor bound 3D structures with PDB ids 4EBV, 4EBW, and 4I4F were utilized for the pharmacophore modeling. The validated PM models were utilized to map a database of 770,550 compounds prepared from ZINC, EXIMED, SPECS, ASINEX, and InterBioScreen, aiming to identify potential allosteric inhibitors. The obtained compounds from screening step were forwarded to molecular docking (MD) for the prediction of binding orientation inside the allosteric site and the results were evaluated with the known FAK allosteric inhibitor (REF). Finally, 14 FAK-inhibitor complexes were selected from the docking study and were studied under molecular dynamics simulations (MDS) for 500 ns. The complexes were ranked according to binding free energy (BFE) and those demonstrated higher affinity for allosteric site of FAK than REF inhibitors were selected. The selected complexes were further analyzed for intermolecular interactions and finally, three potential allosteric inhibitor candidates for the inhibition of FAK protein were identified. We believe that identified scaffolds may help in drug development against FAK as an anticancer agent. [Display omitted] • Three allosteric site-targeting pharmacophore models were generated using PDB ids 4EBV , 4EBW and 4I4F. • The best pharmacophore models were then used to screen five chemical libraries. • Binding mode prediction was made using molecular docking, followed by molecular dynamics Simulations. • Hit compounds showed stable hydrogen bonding with DFG motif proximal residue G563, N551, S601, and D604. [ABSTRACT FROM AUTHOR]

With the increase in electrification, the demand for the functionality and features of electric vehicles (EVs) is increasing, and accordingly, the required weight of copper (Cu) is increasing. Additionally, Cu usage increase as the wiring/functions of autonomous vehicles (AVs) increase. Therefore, limited energy efficiency due to the high mass density of Cu electrical cables has become a challenging issue to be overcome. With this trend, carbon-metal core-shell wire is an attractive lightweight material. It remains a challenge to further improve the properties of previously reported carbon-metal core-shell wire. Here, we report CNTF-Cu-Gr wires obtained by introducing graphene into Cu electroplated on CNTFs. Electroplated Cu was coated with graphene via chemical vapor deposition, which also provided synergetic effects, enabling better thermal and electrical properties. These CNTF-Cu-Gr wires exhibit excellent overall performance in terms of mechanical, electrical, and thermal properties and are lightweight. We expect that these dual core-shell wires will be used in practical applications in the near future. [ABSTRACT FROM AUTHOR]

The deep-injection floating-catalyst chemical vapor deposition (DI-FCCVD) technique is introduced to continuously synthesize carbon nanotubes (CNTs) with high aspect ratio (AR>17000) and high crystallinity (I G / I D > 60) at high production rate (>6 mg/min). In this technique all reactants are injected directly and rapidly into high-temperature reaction zone through thin alumina tube; this process leads to simultaneous thermal decomposition of well-mixed catalyst precursors (ferrocene and thiophene), and thus to formation of uniformly-sized catalyst particles. Carbon nanotube fiber (CNTF) fabricated from high-AR CNT has specific strength of 2.94 N/tex and specific modulus of 231 N/tex, which are comparable to those of the state-of-the-art carbon fiber. Both DI-FCCVD and wet spinning methods are easily scalable to mass production, so this study may enable widespread industrial application of CNTFs. Image 1 [ABSTRACT FROM AUTHOR]

We present a post-treatment method for directly-spun ultra-thick carbon nanotube fibers (CNTFs) with a high linear density of ∼ 6 tex (g km−1), which can possibly meet industrial-scale productivity. The treatment consists of consecutive steps of swelling of CNTFs in chlorosulfonic acid, stretching, and coagulation. The swelling of CNTFs makes even distribution of the CNT bundles, which are the subunits of CNTFs, and thereby promotes the removal of the interstitial voids and macroscopic pores during subsequent coagulation. The stretching straightens tortuous CNT bundles, and thereby facilitates dense packing of aligned bundles along the fiber axis that are evenly distributed by swelling. However, highly-tortuous CNT bundles in the high linear-density CNTF leads to incremental improvement of structure and properties. The stretching is only effective at stretching ratio (R S) > 20%, and both tensile strength and electrical conductivity gradually increase as R S increases, to 27- and 8.7-times at the maximum R S = 100%. We believe that our study on the influence of R S on the structure and properties of high linear-density CNTFs provide a new opportunity for designing the industrial process of the post-treatment to commercialize CNTFs. Image 1 [ABSTRACT FROM AUTHOR]

Despite significant improvements in the synthesis of nitrogen (N)-doped carbon nanotubes (CNTs) and their versatile applications, there has always been a large difficulty in controlling the bonding configuration of N atoms within CNTs. In the current work, we report an effective chemical strategy to synthesize single-walled carbon nanotubes (SWNTs) with 100% of quaternary N via a chlorosulfonic acid(CSA) treatment. In this process, the pyridinic and pyrrolic groups were selectively and completely removed while retaining the quaternary N atoms. The presence of 2.04 at. % of quaternary N atoms within SWNTs was directly identified from a single sharp peak in the N 1s spectra of XPS, and indirectly supported by the downshift of C 1s peak in XPS, the upshift of G'-band in Raman spectroscopy, and the decrease of the work function from 5.46 to 4.59 eV. The doping effect of the quaternary N atoms on the macroscopic properties of SWNT fibers was verified by a large increase in the electrical conductivity from 0.63 to 2.17 MS/m. In perspective, our chemical approach can now be applied to synthesize carbon materials with controlled N functionalities for different applications. Image 1 [ABSTRACT FROM AUTHOR]

The mechanical behaviors of carbon nanotube yarn (CNTY) can be described as collective mechanical behaviors of the components that comprise its hierarchical structures. The internal structures and mechanical behaviors of CNTYs closely resemble those of bio-materials, so we developed a simple mathematical model inspired by the mechanical behaviors of bio-materials to fully describe the mechanical behaviors of CNTYs during tensile testing. The developed model successfully fitted the experimental modulus-strain (M-S) curves of four types of CNTYs that have different internal structures and different M-S curves; this result confirms the generality of the model to describe the mechanical behaviors of CNTYs. The model parameters provide explanations of the structural characteristics of various CNTYs. Image 1 [ABSTRACT FROM AUTHOR]

Abstract An efficient strategy to enhance mechanical and electrical properties of carbon nanotube (CNT) fiber is developed by using resorcinol-formaldehyde (RF) resin as a functional infiltrating agent that can be carbonized under a mild condition. This strategy is a sequential process including infiltration of RF resin into CNT fiber, thermal stabilization and carbonization. The selection of resin and additive, and enhancement mechanism are elucidated by theoretical and experimental approaches. By using this strategy, the tensile strength, modulus, specific tensile strength and electrical conductivity of CNT fiber are enhanced by 8.2, 16.4, 2.1 and 3.6 fold, respectively. Graphical abstract Image 1 Highlights • Mechanical and electrical properties of carbon nanotube (CNT) fiber are enhanced with resorcinol-formaldehyde (RF) resin. • The enhancement mechanism is clearly demonstrated by using experimental analysis and theoretical simulation. • Carbonization of RF resin treated CNT fiber is carried out to further enhance its mechanical and electrical properties. [ABSTRACT FROM AUTHOR]

We investigated the effects of air purifiers and ventilation on the particulate matter PM 2.5 concentration of a semi-outdoor bus terminal using computational fluid dynamics (CFD) simulations. As per the numerical simulation results, the air purifiers alone significantly reduced the PM 2.5 concentration of the bus terminal. The effect of mechanical ventilation units on the PM 2.5 reduction is positive without air purifiers but negative with air purifiers. To understand the role of ventilation on the PM 2.5 reduction, a simple theoretical model was derived based on the mass conservation of the PM 2.5. This model considered the effects of traffic-related PM 2.5 emission, air purifiers, and ventilation. The PM 2.5 concentrations predicted by the proposed model showed good correlation with those from the CFD simulations. Using the model, we suggested that the ratio of the mass emission rate of PM 2.5 to the clean air delivery rate of air purifiers is an important value in determining the effect of ventilation. Moreover, when the background PM 2.5 concentration is higher than this value, the ventilation should be limited to reduce the PM 2.5 concentration of the bus terminal. An additional CFD simulation showed that limiting the ventilation using walls can reduce the PM 2.5 concentration of the bus terminal by 28.6% on average and up to a maximum of 44.2%. The present approach may be useful in improving the health of many commuters by designing openings of bus terminal and efficiently operating mechanical ventilation units. • Reduction of PM 2.5 concentration in a semi-outdoor bus terminal. • Combined effects of air purifiers and ventilation. • Strategies for an efficient operation of mechanical ventilation units. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) foam was utilized as an efficient and durable template to immobilize surface-functionalized nanocellulose, carboxymethylated cellulose nanofibrils (CMCNFs), to address some of the challenges for the application of nanocellulose to industrial water purification, such as its agglomeration, difficulties in separation from effluent, and regeneration. The composite foams exhibited well dispersed CMCNFs in PU matrices with open pore structure; the hydrogen bonds result in the enhancement of mechanical strength, which is another requirement of ideal adsorbents for wastewater treatment. The composite foams show high adsorption capacity and the potential for recyclability. The combination of optimal surface modification of nanocellulose with isolation and immobilization in durable PU foam achieved an efficient and cost-competitive bio-sorbent for heavy metal ions. [ABSTRACT FROM AUTHOR]

Current interest in flexible and stretchable electronics has been amplified because of their remarkable features for numerous applications. Accordingly, compliant efficient thermal management for such electronics is in great demand. However, new materials simultaneously coping with high thermal conductivity and mechanical flexibility have not been sufficiently studied. Here, we report a simple yet highly efficient method to construct three-dimensional (3D) hexagonal boron nitride (h-BN) network in a polymer composite, which is both thermally conductive and mechanically stretchable. 3D h-BN network is easily fabricated by in-situ incorporation of h-BN onto the surface of a water-borne polyurethane (PU) scaffold during polymerization. The 3D h-BN network in the composite film offers high thermal conductivity up to 10 W/m·K while the PU contributes excellent mechanical flexibility such as folding, twisting and stretching. Moreover, the process developed in this study is highly economical and processable to be scaled up without the need of complex equipment or procedure, which will be of great interest to current manufacturing as well as soft and stretchable electronic devices. [ABSTRACT FROM AUTHOR]

Naturally outflowing CO2-rich springs are a natural analogue of the seepage of sequestered CO2 in geological storage sites. In Kangwon district of South Korea, two hydrochemically different types of CO2-rich springs (i.e., Ca-HCO3-type and Na-HCO3-type) occur together in a granitic terrain. Hydrochemical and water-isotope data (i.e., δ18O-δD and tritium) show that Na-HCO3-type springs have experienced significant silicate weathering processes over a long residence time at depths, while Ca-HCO3-type springs were formed by the mixing of Na-HCO3-type springs with shallow groundwater during ascent. In this study, diverse geochemical models including mixing, ion exchange and reaction path were investigated to verify the geochemical processes accounting for the occurrence of two contrasting types of CO2-rich springs. The mixing and ion exchange models reveal that Ca-HCO3-type springs are well explained by reverse cation exchange occurring during the mixing of Na-HCO3-type springs with shallow groundwater. The Na-HCO3-type springs are well explained by the reaction path modeling including the dissolution of silicate minerals (plagioclase, K-feldspar and biotite) and the precipitation of secondary minerals (calcite, kaolinite, muscovite and Mg-beidellite), implying that dissolved carbon is sequestered by calcite precipitation (i.e., mineral trapping). However, the concentrations of K in our modeling results are far below those of K observed in Na-HCO3-type springs, because of the precipitation of muscovite considered in the model, suggesting the partial disequilibrium state of the aquifer during the hydrolysis of K-feldspar under high PCO2 conditions. This result implies that to better predict long-term CO2-water-rock interactions in a geological storage site with abundant K-feldspar, the secondary K-bearing minerals should be carefully predicted, because a target aquifer can be far from chemical equilibrium during the storage period. This study shows that geochemical modeling can be effectively used to predict the hydrochemical changes of groundwater during long-term CO2-water-rock interactions and subsequent leakage toward surface in K-feldspar rich aquifer, although it should be included in a fully coupled computational approach between fluid flow, heat transfer and reactive mass transport processes in the future research. [ABSTRACT FROM AUTHOR]

Nitrophenols(NPs) are highly toxic compounds that occur in various industrial effluents. Herein, we investigated Cu nanoparticle-loaded cellulose nanofibril (CNF/PEI-Cu) aerogels as a catalyst for degrading 4-nitrophenol (4NP) in the wastewater. Non-noble metal based low-cost catalyst material and easily scalable preparation method make CNF/PEI-Cu aerogel as an appropriate catalyst for practical application in 4NP wastewater treatment. Our strategy to improve the loading amount of homogeneously distributed Cu nanoparticles was to functionalize a CNF aerogel using polyethylene imine (PEI), which can bind Cu2+ ions. Porous CNF aerogels with homogenously distributed 20–40 nm Cu nanoparticles were obtained by adsorbing Cu2+ ions and chemically reducing them to Cu metal. The FTIR, XRD, SEM, XPS and ICP-OES analysis were used to confirm the in-situ formation of Cu nanoparticles. In the presence of the CNF/PEI-Cu aerogels, 4NP was effectively reduced to 4-aminophenol (4AP) without loss of the Cu nanoparticles. The activation energy (E a) and reaction rate constant (k app) of the catalytic 4NP reduction reaction by the CNF/PEI2-Cu aerogels were calculated to be E a = 39.56 kJ mol−1 and k app = 0.770 min−1, respectively. The E a is similar or even smaller than the E a values of the corresponding reactions involving noble-metal catalysts, demonstrating that the CNF/PEI-Cu aerogels developed in the present study have strong potential as practical and economical catalysts. [Display omitted] • A cost-effective and scalable catalyst is prepared for nitrophenol(NP) wastewater treatment. • Cu loaded cellulose nanofibril(CNF/PEI-Cu) aerogel promotes 4NP reduction to 4-aminophenol. • Thermodynamic and kinetic behavior of 4NP reduction by CNF/PEI-Cu is investigated. • Activation energy of 4NP reduction reaction is significantly decreased by CNF/PEI-Cu. [ABSTRACT FROM AUTHOR]

Abstract: In the Jungwon area, South Korea, two contrasting types of deep thermal groundwater (around 20–33 °C) occur together in granite. Compared to shallow groundwater and surface water, thermal groundwaters have significantly lower δ 18O and δD values (>1‰ lower in δ 18O) and negligible tritium content (mostly <2 TU), suggesting a relatively high age of these waters (at least pre-thermonuclear period) and relatively long subsurface circulation. However, the hydrochemical evolution yielded two distinct water types. CO2-rich water (P CO2 =0.1 to 2 atm) is characterized by lower pH (5.7–6.4) and higher TDS content (up to 3300 mg/L), whereas alkaline water (P CO2 =10−4.1–10−4.6 atm) has higher pH (9.1–9.5) and lower TDS (<254 mg/L). Carbon isotope data indicate that the CO2-rich water is influenced by a local supply of deep CO2 (potentially, magmatic), which enhanced dissolution of silicate minerals in surrounding rocks and resulted in elevated concentrations of Ca2+, Na+, Mg2+, K+, HCO3 − and silica under lower pH conditions. In contrast, the evolution of the alkaline water was characterized by a lesser degree of water–rock (granite) interaction under the negligible inflow of CO2. The application of chemical thermometers indicates that the alkaline water represents partially equilibrated waters coming from a geothermal reservoir with a temperature of about 40 °C, while the immature characteristics of the CO2-rich water resulted from the input of CO2 in Na–HCO3 waters and subsequent rock leaching. [Copyright &y& Elsevier]