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Inorganic two-dimensional (2D) materials offer a new approach to control mass diffusion at the nanoscale. Controlling ion transport in nanofluidics is key to energy conversion, energy storage, water purification, and numerous other applications wherein persistent challenges for efficient separation must be addressed. We herein discuss the recent development of 2D membranes in the emerging field of energy harvesting, water desalination, and proton/Li-ion production in the context of green energy and environmental technology. We highlight the fundamental mechanisms, 2D membrane fabrication, and challenges toward practical applications. Finally, we outline the fundamental issues of thermodynamics and kinetics along with potential membrane designs that must be resolved to bridge the gap between lab-scale experiments and production levels. This article is protected by copyright. All rights reserved.

A two-photon tandem absorption E-BiVO4/BPQDs/OL-OEC photoanode with superior light absorbability and photocurrent density.

We extend the usual notion of fully commutative elements from the finite Coxeter groups to the complex reflection groups. We decompose the sets of fully commutative elements into natural subsets according to their combinatorial properties, and investigate the structure of these decompositions. As a consequence, we enumerate and describe the form of these elements for the complex reflection groups.

Scanning probe microscopy techniques, such as atomic force microscopy and scanning tunnelling microscopy, are harnessed to image nanoscale structures with an exquisite resolution, which has been of significant value in a variety of areas of nanotechnology. These scanning probe techniques, however, are not generally suitable for high-throughput imaging, which has, from the outset, been a primary challenge. Traditional approaches to increasing the scalability have involved developing multiple probes for imaging, but complex probe design and electronics are required to carry out the detection method. Here, we report a probe-based imaging method that utilizes scalable cantilever-free elastomeric probe design and hierarchical measurement architecture, which readily reconstructs high-resolution and high-throughput topography images. In a single scan, we demonstrate imaging with a 100-tip array to obtain 100 images over a 1-mm2 area with 106 pixels in less than 10 min. The potential for large-scale tip integration and the advantage of a simple probe array suggest substantial promise for our approach to high-throughput imaging far beyond what is currently possible.

Cadmium sulfide (CdS) is a semiconducting absorber for photoelectrochemical (PEC) hydrogen production with suitable electronic band structures. However, it suffers from severe photocorrosion and rapid charge recombination during the desired PEC reactions. Herein, we describe the identification of the optimal junction thickness of CdS/MoS

We deal with Temperley-Lieb algebras of type B, extending the result in [3, §6]. By completing the relations coming from a presentation of the Temperley-Lieb algebra, we find its Gröbner-Shirshov basis to obtain the corresponding set of standard monomials. The explicit multiplication table between the monomials follows naturally.

Exploring new single, active photocatalysts for solar-water splitting is highly desirable to expedite current research on solar-chemical energy conversion. In particular, Z-scheme-based composites (ZBCs) have attracted extensive attention due to their unique charge transfer pathway, broader redox range, and stronger redox power compared to conventional heterostructures. In the present report, we have for the first time explored Cu

In this study, electroless-plating of a nickel-phosphor (Ni&ndash, P) thin film on surface-controlled thermoelectric elements was developed to significantly increase the bonding strength between Bi&ndash, Te materials and copper (Cu) electrodes in thermoelectric modules. Without electroless Ni&ndash, P plating, the effect of surface roughness on the bonding strength was negligible. Brittle SnTe intermetallic compounds were formed at the bonding interface of the thermoelectric elements and defects such as pores were generated at the bonding interface owing to poor wettability with the solder. However, defects were not present at the bonding interface of the specimen subjected to electroless Ni&ndash, P plating, and the electroless Ni&ndash, P plating layer acted as a diffusion barrier toward Sn and Te. The bonding strength was higher when the specimen was subjected to Ni&ndash, P plating compared with that without Ni&ndash, P plating, and it improved with increasing surface roughness. As electroless Ni&ndash, P plating improved the wettability with molten solder, the increase in bonding strength was attributed to the formation of a thicker solder reaction layer below the bonding interface owing to an increase in the bonding interface with the solder at higher surface roughness.

For Temperley–Lieb algebras of types [Formula: see text] and [Formula: see text], we construct their Gröbner-Shirshov bases and the corresponding standard monomials

Hydrogen generation by water electrolysis has been comprehensively studied for several decades, although it still faces many difficulties in commercialization due to low efficiency. Even though IrO2 and RuO2 have superior activities to oxygen evolution reaction (OER), such novel metal catalysts still need high overpotential compared to hydrogen evolution reaction. To overcome the limitation of OER, former researches have been studied with various materials which are cheaper and perform better than the novel metal-based electrocatalysts. Among them, nickel is considered as the best catalyst candidate due to hydroxide state transformation between Ni(OH)2 and NiOOH during the surface reaction. Apart from the intrinsic properties, the morphology construction to the nanoscale structure is another useful way to enlarge the surface area, which is directly correlated to the overpotential decrease. Nanostructuring can inhibit continuous growth of bubbles on the surface and detach much easily. The bubble blocking effect on the electrode surface has been deeply studied within mechanical category but this effect has been poorly regarded for enhancement of the OER activity of the electrode. Also, the bimetallic system of nickel/iron chosen in this research enables great improvement for OER. Herein, we synthesized three-dimensional ordered nanoporous mesh-like (3D-NM) nickel electrode by the photolithography method, which outperforms conventional porous nickel electrode. Successfully synthesized ordered nanoporous mesh-like structure provides highly extensive surface area within thickness of only 5 μm. In addition, we investigated that fast bubble formation/detachment from the pore can reduce the bubble blocking effect, which disturbs supply of electrolyte to the catalyst surface. 3D-NM nickel electrode only generates 12 times smaller extraordinary small bubbles compared to the typical bubbles in basic electrolyte. In line with the size of bubbles, impedance during the OER with 3D-NM nickel electrode smoothly undergoes while the nickel foam shows unstable graph. Owing to the enlarged surface area and the fast bubble formation/detachment effect, overpotential measured at 10 mA cm-2 was 372 mV and the calculated Tafel slope was 94.4 mV dec-1. Through the unique nanoporous structure of nickel electrode, outstanding stability for 50 hours was achieved. To further improve the OER activity of as-prepared 3D-NM nickel electrode, the decoration of nickel and iron was conducted. The final 3D-NM NiFe electrode showed 261 mV of overpotential at 10 mA cm-2 with 43.8 mV dec-1 of Tafel slope. Figure 1

Despite longstanding controversy, TiO2 polymorphs heterojunction composed of anatase and rutile outperform the individual ones because of the energetic type-II band alignment at the heterojunction interface. Apart from the conventional polymorphs interface, the surface disordered TiO2 has been drawing interest and considered as an unpredictable strategy while is regarded as a fact for dramatically enhancing photocatalytic activity. However, introduction and localization of the disordered layer within conventional TiO2 nanoparticles with the heterojunction has remained a big challenge. Here we report a selective positioning of a disordered layer with different thickness ranges in between the anatase and rutile phases by a conceptually different synthetic route for highly efficient novel metal-free photocatalytic H2 production (denoted as DE-P25). With two step disorder engineering: Phase selective disordering of rutile TiO2 and thermal annealing process at temperature lower than phase transformation, the multiple heterojunction in DE-P25 single nanoparticle with the disordered layer of 2~3 nm could be synthesized which is confirmed by high resolution-TEM, electron energy loss spectroscopy (EELS) and inline electron holography mapping for the first time. EELS Ti-L2,3 spectrum geometry of DE-P25 showed distinctive oxygen-deficient variation between the two crystals which corresponds with the drastic decrease of potential and negative charge density within the disordered layer due to localized unpaired electrons. PL decay profiles exhibiting ultra-fast charge migration of DE-P25 indicate that the rutile phase incorporated with the disordered layer in the TiO2 nanoparticle induces dominant direct excition formation and reduces the self-trap of charge carriers, thus suppressing the electron/hole recombination, which perfectly coincides with the holography mapping analysis. This multiple heterojunction in single TiO2 nanoparticles composed of crystalline anatase/disordered rutile/ordered rutile demonstrate not only superior interfacial charge separation efficiency, but also novel-metal free surface reactivity, which synergistically yields ~140 times higher H2 production rate than conventional anatase and rutile single heterojunction system. Figure 1

We develop the combinatorics of Young walls associated with higher level adjoint crystals for the quantum affine algebra U"q(sl"[email protected]^). The irreducible highest weight crystal B(@l) of arbitrary level is realized as the affine crystal consisting of reduced Young walls on @l. We also give a Young wall realization of the crystal B(~) for U"q^-(sl"[email protected]^).

All of the automorphisms of the Fibonacci poset Z(r) are determined (r ∈ \Bbb N). A problem of Richard P. Stanley from 1988 is thereby solved.

Nous generalisons au cas des groupes de reflexions complexes la definition de Rouquier des “familles de caracteres” des groupes de Weyl (definies anterieurement par Lusztig). Nous mettons en evidence le fait que cette notion depend d'une maniere essentielle du choix de la deformation de l'algebre de groupe appelee “algebre cyclotomique”, et nous calculons ces familles pour toutes les algebres cyclotomiques des familles infinies de groupes de reflexions complexes qui generalisent les familles infinies de groupes de Weyl.

Resume En vue d'applications au calcul des tables de caracteres des algebres de Hecke, on presente un algorithme permettant, a partir d'un element quelconque σ e S n , de construire un element de longueur maximale dans la classe de conjugaison de σ .

In order to investigate the prevalence of sexually transmitted viruses such as human papillomavirus (HPV) and herpes simplex virus (HSV) in Korean commercial sex workers (CSWs), we selected 188 CSWs (age range 20-44 years, median age 24 years) who regularly visited one public health center in Seoul, Korea. HPV genotypes were analyzed by using a HPV DNA chip, and an enzyme-linked immunosorbent assay (ELISA) was used to detect type-specific IgG against HSV2 antibody identifying seropositivity for HSV2 infection. Polymerase chain reaction (PCR) was performed with specific primers to detect HPV and HSV1/2 in cervical swabs from the CSWs. The prevalence of HPV infection was 83.5% in 188 cervical swab specimens and the main high-risk HPV genotypes were HPV16, 18, 56, and 58. The principal low-risk HPV genotypes were HPV6 and 11. The prevalence of HSV1/2 DNA was 13.8% and HSV2 seroprevalence was 86.2%. These results suggest that high frequencies of HPV and HSV2 infection might contribute to the rapid spread of STD viruses in CSWs in Korea. Additionally, an understanding of why high-risk HPV genotypes are so prevalent could provide guidelines for prophylactic vaccine development in Korea.

There remains to be issues regarding radiofrequency catheter ablation (RFCA) in pediatric patients that are different to those involving adults. This study was performed to determine the efficacy and safety of RFCA in pediatric patients.During the period from 1992 to 2003, 2,734 patients underwent RFCA and 131 pediatric patients who wereor =15 years old (70 males, mean age 12.0+/-3.1 years) were analyzed, retrospectively. The number of accessory pathways (APs) mediating atrioventricular re-entrant tachycardia was 93 (71.4%) and atrioventricular nodal re-entrant tachycardia (AVNRT) was 27 (20.5%). The most common indications for the RFCA were the ;patient's choice' in 94 (71.2%) and 'medically refractory tachycardia' in 29 (22.0%). The age-related indication of the ;patient's choice' was 80.4% (82 of 102) for those10 years old and 40.0% (12 of 30) for thoseor =10 years old (p=0.01). RFCA was performed without sedation in 87.3% (89 of 102) of the subjects10 years old as compared to 20.0% (6 of 30) of thoseor =10 years old (p=0.01). The success rate was 92.8% (90 of 97 APs) for the ablation of APs, and 96.3% (26 of 27) for that of AVNRT. The overall complication rate was 3.8% (5 of 131). During a mean follow-up duration of 13.1+/-2.5 months, the freedom of recurrence was 87.8% (79 of 90) for the arrhythmia associated with APs and 92.3% (24 of 26) for AVNRT.RFCA in pediatric patients had a good success rate with acceptable recurrence and complication rates when compared to adult patient results. Therefore, RFCA could be considered as the first line of therapy for arrhythmias with concealed and manifested APs and AVNRT in pediatric patients.

Motivated by the work of Lusztig on the families of Irr(W) for the Weyl group W of any type, especially for the types Br and Dr, we described in the article [M. Broué and S. Kim, Familles de caractères des algèbres de Hecke cyclotomiques, Adv. Math. 172 (2002) 53–136] the families of the characters of G(e,1,r) and G(e,e,r), which are the blocks of the cyclotomic Hecke algebras over an appropriate ring called “Rouquier ring.” The results coincide with the results of Lusztig on the Weyl groups of types Br and Dr when specializing the parameters of the Hecke algebras. In this paper, generalizing this work to the whole series of G(de,e,r) which is a normal subgroup of G(de,1,r) of index e, we extend the results of Broué and Kim, op. cit.