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In the overall aromaticity of a molecular system, the magnitude of σ -aromaticity influences the degree of bond length averaging in the molecular geometry, while the magnitude of π -aromaticity reflects the strength of π -electron delocalization, subsequently affecting the electronic transport properties of the entire molecular system. Simultaneously, the aromaticity type of a molecular system is primarily determined by the symmetry of the innermost π molecular orbitals. In this study, we conducted computational simulations of the aromaticity and electronic transport properties of compounds, including C8H8Cu2 with p π – d π delocalization effects and C12H8 with p π – p π delocalization effects, along with their Li derivatives. Based on calculated NICS values, ring current directions, molecular structural configurations and the symmetry of the innermost π molecular orbitals, we clarified the aromaticity types of the molecular systems. Combined with the analysis of molecular electrical conductivity properties, we gained insights into the fundamental attributes of Li-bridge bonds in Li derivatives and the factors influencing electronic transport pathways. Consequently, we established a relationship between the aromaticity of molecular systems and their electronic transport properties. To a certain extent, a novel criterion for evaluating molecular aromaticity is proposed from the perspective of single-molecule electronics. Through the analysis of molecular aromaticity and electrical conductivity, we have clarified that planar Craig-Möbius type π -aromaticity and non-planar Heilbronner-Möbius type σ -aromaticity determine the molecular electron transport capabilities. Additionally, by combining the analysis of bonding types and electron transport pathways, we explain the reason why the C 1 2 H8Li4 molecule, satisfying the 4n electron rule, exhibits Heilbronner-Möbius π -antiaromaticity, which primarily arises from the localization of electrons in its Li-bridged bonds. This research contributes to understanding the fundamental properties of molecular bonding, particularly Li-bridged bonds, and offers a new method for assessing aromaticity from the perspective of single-molecule electronics. [ABSTRACT FROM AUTHOR]

BACKGROUND: Palladium nanoparticles can act as a shuttle to accelerate the extracellular electron transfer (EET) by exoelectrogens. Through the EET process, microorganisms drive the redox cycle of many substances. The palladium nanoparticle has a variety of catalytic activities and activities can be significantly improved by combining with the active effects of microorganisms. RESULTS: In this study, Staphylococcus saprophyticus JJ‐1 was utilized as a biological template carrier to synthesize palladium nanoparticles that were immobilized on the bacterial surface. The morphology and composition of palladium were characterized by various techniques including transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. Furthermore, the hydrogenation activity of the synthesized Pd was tested at room temperature and atmospheric pressure using methyl orange as a model pollutant. Electrochemical characterization was carried out by cyclic voltammetry and potentiostatic measurements. The research demonstrated that palladium nanoparticles acted as both electronic mediators and catalysts in the dye reduction process, while S. saprophyticus JJ‐1 contributed to stabilizing nanoparticles and electrochemical activity. The synergistic effect between these two components significantly enhances MO degradation efficiency. CONCLUSION: This study presented an energy‐saving method to synthesize an integrated catalyst based on the synergistic interaction between biomass and nanoparticles, offering a novel approach for developing environmentally friendly, cost‐effective, and efficient integrated catalysts. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

The p–n type Sm2WO6-Co9S8 heterojunction with two-dimensional coupling interface was successfully synthesized by electrostatic self-assembly. The unique rhombic morphology of Sm2WO6 and Co9S8 nanoparticles also effectively improve the light utilization efficiency. The intervention of Co9S8 enhances the visible light absorption capacity of m2WO6/Co9S8. The Sm2WO6/Co9S8 greatly increases the specific surface area and provides a rich reaction site. Recombination of photogenerated carriers in Sm2WO6/Co9S8 heterojunctions is effectively inhibited. The p–n type Sm2WO6-Co9S8 heterojunction results show that the optimized Sm2WO6/Co9S8 heterojunction exhibits significant hydrogen evolution activity, and the optimal Sm2WO6/Co9S8-25 composite has 117.5 μmol hydrogen evolution activity, it's close to four times Co9S8, close to 143 times Sm2WO6. The stability of the composite Sm2WO6/Co9S8 is the better. Under the built-in electric field induced by p–n heterojunction, using of p–n heterojunction interactions and electron transport modes, the Sm2WO6/Co9S8 can effectively achieve the remarkable effect of its internal carrier separation. This work also provides new opportunities for studying rare earth element tungstate photocatalysts. [ABSTRACT FROM AUTHOR]

Using the Landauer–Buttiker formalism and the nonorthogonal tight-binding Hamiltonian with NTBM parametrization, the electron transmission and conductivity of metal armchair-type nanotubes of subnanometer diameter are studied. We consider the effect of various structural defects (Stone–Wales defect, monovacancy, replacing a nitrogen atom) and radicals adsorbed on the nanotube surface (H, O, OH, COOH) on the electronic characteristics of carbon nanotubes (CNTs). It is found that structural defects and adsorbates have different effects on their conductivity. In this case, two competing processes are observed. On the one hand, this is a weakening of the conductive properties of CNTs due to the increase in the number of scattering centers, and, on the other hand, the increase in conductivity due to structural relaxation processes. [ABSTRACT FROM AUTHOR]

The hydrothermal preparation of NiCo 2 S 4 /ZnIn 2 S 4 photocatalysts with different mass ratios is studied. Ni-cobalt bimetallic sulfide nanosheets are grown on zinc-indium bimetallic sulfide to form a compact heterojunction. First, both NiCo 2 S 4 and ZnIn 2 S 4 exhibit N-type semiconductor characteristics, a heterojunction formed by both can reduce the surface reaction energy barrier and use its synergy, strengthening the charge self-diffusion between the two semiconductors, it means the formation of a strong electric field. From the electron transfer path and band structure, NiCo 2 S 4 /ZnIn 2 S 4 has S-scheme heterojunction characteristics. NiCo 2 S 4 is a reducing photocatalyst (RP), and ZnIn 2 S 4 is an oxidative photocatalyst (OP). Under the action of built-in electric field (BIEF), strong photogenic electrons and holes exist in CB of RP (NiCo 2 S 4) and VB of OP (ZnIn 2 S 4). Thus, the overall redox capacity of the NiCo 2 S 4 /ZnIn 2 S 4 heterojunction is enhanced. Using visible light, the composite material can be used for photocatalytic hydrogen production. It is further shown that the composite material has a good effect in photocatalytic hydrogen production under the sensitizer eosin Y (EY) system. The optimal hydrogen production is about 221.75 μmol when the mass ratios of NiCo 2 S 4 /ZnIn 2 S 4 is 20%, and the photocatalytic activity of the composite is about 47 times that of ZnIn 2 S 4. Notably, the stability of the composites is the better. A reasonable photo-catalytic mechanism is proposed based on the band gap and photoelectrochemical properties of heterojunction. • Nanosheets NiCo 2 S 4 innovatively decorated on globular structure ZnIn 2 S 4 form S-scheme heterojunction. • The morphology of nanosheets NiCo 2 S 4 is innovative in the field of NiCo 2 S 4 /ZnIn 2 S 4 photocatalysis. • The heterojunction can short transfer route to promote electron efficient transport. • Dispersion of NiCo 2 S 4 on ZnIn 2 S 4 is important for the heterojunction HER activity and stability. [ABSTRACT FROM AUTHOR]

• Applying stress on the S-hyperdoped silicon can change the electronic structure of the material obviously and lead to the insulator-to-metal transition (IMT). • The IMT will occur when the conduction band comes very close to the intermediate-band and the electron filling in the conduction band increases under the critical stress. • The critical stresses for the IMT are different in different directions due to the nonuniform distribution of dopant. In this work, the effect of the stress on the electronic structure and electronic transport properties of S-hyperdoped silicon, which is an intermediate-band (IB) photovoltaic material, was studied in detail by combining the density functional theory and nonequilibrium Green's function methods. We found that applying stress on the material could lead to the insulator-to-metal transition (IMT), which is crucial for improving the performance of the IB material. Under the critical stress for the IMT of the material, the IB and the conduction band (CB) have not been fully merged together, which is slightly different from the dopant-concentration-induced IMT. The critical stress exhibits direction-dependent property for material with nonuniform distribution of dopant, and it is smaller in the direction that shows lower dopant density. [ABSTRACT FROM AUTHOR]

Medium-chain carboxylic acids (MCCAs) show great promise as commercial chemicals due to their high energy density, significant product value, and wide range of applications. The production of MCCAs from waste biomass through coupling chain extension with anaerobic fermentation represents a new and innovative approach to biomass utilization. This review provides an overview of the principles of MCCAs production through coupled chain extension and anaerobic fermentation, as well as the extracellular electron transfer pathways and microbiological effects involved. Emphasis is placed on the mechanisms, limitations, and microbial interactions in MCCAs production, elucidating metabolic pathways, potential influencing factors, and the cooperative and competitive relationships among various microorganisms. Additionally, this paper delves into a novel technology for the bio-electrocatalytic generation of MCCAs, which promotes electron transfer through the use of different three-dimensional electrodes, various electrical stimulation methods, and hydrogen-assisted approaches. The insights and conclusions from previous studies, as well as the identification of existing challenges, will be valuable for the further development of high-product-selectivity strategies and environmentally friendly treatments. [Display omitted] • The extracellular electron transfer pathway of producing MCCAs is summarized. • A new technique of bioelectrocatalytic generation of MCFAs is introduced. • MCFA provides a new research direction for the energisation of waste resources. • Highlighting several strategies for efficient MCFA extraction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn 0.2 Cd 0.8 S formed a stable heterojunction with CeO 2. • Mn 0.2 Cd 0.8 S/CeO 2 achieves efficient photocatalytic HER. • The reaction mechanism of the catalyst is speculated. • The recombination of photogenerated carriers was effectively suppressed. • The band gap and state density of catalyst were calculated by DFT. The Mn 0.2 Cd 0.8 S/CeO 2 heterojunction is synthesized by means of hydrothermal coupling. Short rod-like Mn 0.2 Cd 0.8 S is wrapped in leaf like CeO 2 to construct a tight heterointerface, which stimulated the photocatalytic activity to the great extent. Due to the remarkable catalytic and electrochemical properties of Mn 0.2 Cd 0.8 S, the CeO 2 surface active site is driven. CeO 2 has excellent specific surface area, suitable pore volume aperture and Mn 0.2 Cd 0.8 S match to optimize the internal interface charge transfer path. At the same time, the heterointerface can coordinate the interface electron flow and promote the H 2 reduction ability. The results show that the optimal hydrogen production of Mn 0.2 Cd 0.8 S/CeO 2 with S-type heterostructure is 291.8 μmol, and the internal lattice and surface morphology of Mn 0.2 Cd 0.8 S/CeO 2 are not easily damaged due to good catalytic stability. The photocatalytic mechanism of Mn 0.2 Cd 0.8 S/CeO 2 is studied by finding the short distance interfacial charge transfer path and enriching the photogenerated electrons required for hydrogen evolution. [ABSTRACT FROM AUTHOR]

The quantum transport properties of ZnO devices with five different bulk configurations are investigated with numerical methods. The calculation results reveal that the transport property at a higher energy range can be tuned by changing the length of central scattering. By substituting some Zn atoms with Cu atoms, it is found that the doped Cu atoms have an obvious effect on the quantum properties at the entire energy range investigated, and could result in different transmission. The properties of ZnO devices are also influenced by the doping positions of Cu atoms. The tuning mechanism relies on the shifting of carrier distributions in the scattering center of the device. [ABSTRACT FROM AUTHOR]

The addition of carbon materials to semiconductor catalyst systems can boost the activity of photocatalytic H2 production substantially. Herein, we prepared a series of carbon nanotube/ZnIn2S4 (CNT/ZIS) composites with different contents of CNTs through a simple hydrothermal process and investigated the effect of CNTs on hydrogen evolution performance of ZIS in detail. The electron–hole behavior of CNT/ZIS is studied by photocurrent density, linear sweep voltammetry, steady state, and transient fluorescence spectra. Meanwhile, its optical properties have been studied. Comprehensive experimental characterization and theoretical research reveal that CNTs can not only enhance the visible-light absorption property of composite materials but also efficiently separate the photoinduced carriers and supply more active sites. In consequence, CNT/ZIS exhibits superior photocatalytic H2 evolution. The optimal sample has a hydrogen production rate of 8904.2 μmol·g–1·h–1 under visible-light irradiation, which is 13.2 times higher than that of bare ZIS. Our work offers a simple, cheap, and green method for improving the photocatalytic performance of photocatalysts toward practical applications. [ABSTRACT FROM AUTHOR]

Unfavorable electron recombination, which hinders the efficiency of dye-sensitized solar cells (DSSCs), usually occurs at the TiO2/dye/electrolyte interface on a photoanode. Polyoxometalates (POMs), as good electron acceptors, can be used as electron-transfer materials in DSSCs to improve electron transport in TiO2 and reduce electron recombining on the interface of a photoanode. In this paper, the pure inorganic sandwich-type POM Na9[Na3(H2O)6Cu3(H2O)3(SbW9O33)2]·40H2O (Cu3Na3POM) was mixed with TiO2 to form nanocomposites by simple sol-gel method. X-ray photoelectron spectroscopy (XPS) proved that Cu3Na3POM and TiO2 combined. Then the nanocomposite was doped with P25 to form Cu3Na3POM@TiO2/P25 photoanodes which were applied to the DSSCs. The Cu3Na3POM improved the transfer and recombination of electrons in the photoanode, proved by open circuit voltage decay (OCVD) and electrochemical impedance spectroscopy (EIS). Scanning electron microscopy (SEM) and ultraviolet-visible (UV-vis) absorption spectra showed that Cu3Na3POM optimized the morphology of the photoanode and the adsorption capacity of dye. The electrochemical test showed that the photoelectric conversion efficiency of DSSCs with Cu3Na3POM@TiO2/P25 photoanodes was enhanced to 6.91%, which was 13.66% higher than the DSSCs without Cu3Na3POM. [ABSTRACT FROM AUTHOR]

Insulator-to-metal (I–M) transition is crucial for an intermediate-band (IB) photovoltaic material to suppress the non-radiative recombinations and improve its efficiency. Nevertheless, the mechanism and critical condition of the I–M transition is not clear yet. In this work, the critical conditions of the I–M transition in two types of Si-based IB materials were studied by combining the molecular dynamics simulations and Landauer transmission calculations. It shows that the I–M transition of the substitutional configuration of S will occur when the filled IB is expanded and merged with the conduction band, which fulfills the Mott transition theory. But this type of IB material is not a standard IB material proposed by Luque. For the substitutional configuration of N, which can be regarded as a standard IB material, the I–M transition would be occurred when the partially-filled IB is expanded and the localization of the carriers in the IB is weakened. The metallic state of the IB material is different from typical metals and they still exhibit some semiconductor properties at low temperature.

The quantum transport properties of ZnO devices with five different bulk configurations are investigated with numerical methods. The calculation results reveal that the transport property at a higher energy range can be tuned by changing the length of central scattering. By substituting some Zn atoms with Cu atoms, it is found that the doped Cu atoms have an obvious effect on the quantum properties at the entire energy range investigated, and could result in different transmission. The properties of ZnO devices are also influenced by the doping positions of Cu atoms. The tuning mechanism relies on the shifting of carrier distributions in the scattering center of the device.

This concept delves into quantum particle transport at the nanoscale, with a particular focus on how electrons move through molecular circuits. The thriving field of single molecular electronics benefits from the unique electrical and other properties of nanostructures. It concentrates on single molecular junctions that serve as bridges between electrodes. In this context, the electronic correlation-induced many-body effect gives rise to resonant states. These states, along with conductance, depend on electron spin. Thus, the field acts as a bridge between quantum and macroscopic worlds, unveiling unique behaviors of electrons. Additionally, external factors, such as magnetic fields and voltages, offer means to control the electron correlation in these junctions., (© 2024 The Authors. ChemPhysChem published by Wiley-VCH GmbH.)

In this study, Zn, S, and P co-doped nitrogen N -enriched carbon (ZnSP/NC) was successfully fabricated as an efficient electrocatalyst for the hydrogen evolution reaction (HER) process via pyrolysis, sulfurization, and phosphorization. The metal Zn derived from zeolitic imidazolate framework-8 (ZIF-8) was combined with the S element to form ZnS nanoparticles, and then embedded in N -enriched carbon during the sulfurization process. Following this, the P element was well-dispersed in the catalyst via phosphorization. It was found that ZnSP/NC exhibits excellent electrocatalytic activity when used as a catalyst for the HER process. ZnSP/NC, with an overpotential of 171 mV and a Tafel slope of 54.78 mV dec−1, demonstrates superior electrocatalytic activity as compared to Zn/NC (277 mV, 92.34 mV dec−1) and ZnS/NC (241 mV, 76.41 mV dec−1). During the HER process, ZnS and P serve as active sites, while the N -enriched carbon provides reliable electronic transmission. The synergistic effects among the ZnS, P, and N -enriched carbon result in an excellent electrocatalytic activity of ZnSP/NC for the HER process. Image 1 • ZnSP/NC was prepared via pyrolysis, sulphurization and phosphorization processes. • ZnSP/NC requires a low overpotential of 171 mV and a Tafel slope of 54.78 mV dec-1. • ZnS, P, and N-enriched carbon results in the outstanding HER activity of ZnSP/NC. [ABSTRACT FROM AUTHOR]

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study represents an empirical model of cytosine‐based optical molecular switch. This possible biomolecular switch has been designed using the first principle approach which is based on density functional theory and non‐equilibrium Green's function. The quantum‐ballistic transport property and current–voltage (I–V) characteristics of cytosine‐based optomolecular switch have been investigated at 25 THz operating frequency. The influence of highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) gaps on the electronic transmission and I–V characteristics has been discussed in detail. The aim of this study is to highlight the minimum conformational change during a single ON–OFF switching cycle. The biomolecule comprises switching behaviour when converts from straightened to twisted form during photo‐excitement. The straightened and twisted forms of the molecule are represented as logic '0' and logic '1', respectively. This p and n regions of this switch has been made using electrical doping process. The current through the twisted form of the cytosine biomolecule is ∼1000 times higher than the straightened form. The maximum switching ratio 62.1 is obtained at 1 V bias. The origin of the switching behaviour of the biomolecule can be interpreted by quantum–ballistic transport model along with HOMO–LUMO gaps. [ABSTRACT FROM AUTHOR]

A new technique of polarization doping was adopted to improve NO 2 gas sensing properties of the polypyrrole (PPy) sensor. PPy nanosheets polarization doped with sodium dodecyl benzenesulfonate (SDBS) were synthesized by low-temperature polymerization. The semiagglomerated PPy nanosheets were well-dispersed and a large specific surface areas due to the introduction of dodecyl benzenesulfonate (DBS). The DBS doped PPy sensor shows excellent NO 2 sensing performance. Polarization of sulfonate ions to PPy enhanced the adsorption ability of NO 2 with the synergistic effect of NO 2 . The adsorption energy (-0.676 eV) and electron transfer (0.521 |e|) of PPy to NO 2 increased greatly after doping. An unoccupied electron state is observed in the valence band electron structure of PPy/DBS after the adsorption of NO 2 by calculations of Density Functional Theory (DFT). The intermolecular synergy between NO 2 and PPy/DBS causes a strong polarization, resulting in a high polarization potential, which enhances the NO 2 sensing performance of PPy sensor. It is of great significance to develop NO 2 detection device based on PPy that works at room temperature.

We consider two bidimensional random models characterised by the following features: (a) their Hamiltonians are separable in polar coordinates and (b) the random part of the potential depends either on the angular coordinate or on the radial one, but not on both. The disorder correspondingly localises the angular or the radial part of the eigenfunctions. We analyse the analogies and the differences which exist between the selected 2D models and their 1D counterparts. We show how the analogies allow one to use correlated disorder to design a localisation length with pre-defined energy dependence and to produce directional localisation of the wavefunctions in models with angular disorder. We also discuss the importance of finite-size and resonance effects in shaping the eigenfunctions of the model with angular disorder; for the model with disorder associated to the radial variable we show under what conditions the localisation length coincides with the expression valid in the 1D case.

[Display omitted] • NiFe-LDH@Ni x Co y Se 2 /NF nanosheets heterojunction are synthesized via two-step facile electrodeposition method. • A heterostructure with abundant Ni x Co y Se 2 nanospheres grown on the surface of NiFe-LDH nanosheets, which has superior OER performance (η 100 = 265.5 mV) in high current density and show great durability and reversibility. • NiFe-LDH@Ni x Co y Se 2 /NF nanosheets heterojunction improve large surface area and induce electron redistribution in surface through charge transfer to get optimal OER performance. Low-cost and high-efficiency electrocatalysts produced by constructing the interfacial heterostructure have attracted more attention in oxygen evolution reaction (OER). Herein, we synthesize a three-dimensional (3D) heterogeneous structure of Ni x Co y Se 2 nanospheres loaded onto NiFe hydroxide (NiFe-LDH) nanosheets via bare nickel foam (NF) two-step electrodeposition. The optimal NiFe-LDH@Ni x Co y Se 2 /NF nanosheets heterojunction electrocatalyst is verified with an excellent OER performance in 1.0 M KOH solution, which only requires a low overpotential of 265.5 mV and 297.8 mV to drive high current density of 100 mA cm−2 and 500 mA cm−2, respectively, long-term durability of more than 60 h at 100 mA cm−2, and an extremely low Tafel slope of 57.5 mV dec−1. Meanwhile, due to the dramatic improvement in OER performance, there is an enhancement in the overall water-splitting activity of the NiFe-LDH@Ni x Co y Se 2 /NF nanosheets heterojunction, attaining a current density of 20 mA cm−2 at the low cell voltage of 1.65 V. As a result, it shows the importance of constructing highly efficient OER catalyst with the rational design of heterostructures. The enhanced catalytic performance can be attributed to the large exposed electrocatalytic active sites accessible and constructed an efficient electronic transmission channel by eliminating contact resistance. [ABSTRACT FROM AUTHOR]

In this paper we have investigated the electronic transmission of systems electrode–benzene–electrode using the Landauer approach. The effect of different electrodes made of metal (Au) and semiconductors (Si, TiO 2 ) is investigated. These three electrodes are compared between them and the results show that the electronic transmission of benzene junctions, when using semiconductor electrodes, is associated to a gap in transmission which is due to the electrodes band gap. As a consequence, a threshold voltage is necessary to obtain conducting channels. [ABSTRACT FROM AUTHOR]

Today, the amazing speed of development of information technology and informatics industry, causing major changes in the handling money and resources in areas that are new concepts as electronic banking and electronic transmission provided. These two concepts, the creator of a new type of banking under the Banking electronics. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile (PAN) has slow surface dynamics due to its low electron transport capacity, which greatly limits its application in the extraction of uranium (U(VI)) from seawater. Here, we propose a local conjugation domain (LCD) structure between adjacent microdomains of cyclized polyacrylonitrile (CPAN) with different conjugation structures. This structure uses the potential difference between different degrees of conjugate domains to form a built-in field that promotes charge separation. Cyclized polyacrylonitrile amideoxime (CPAO) formed by hydrolyzing the cyano groups that are not involved in conjugation in CPAN can better capture the U(VI) in seawater. After floating in marine for 30 days, the U(VI) extraction capacity of CPAO can reach 5.2 mg g−1, which is 3 times that of PAO. This LCD strategy can be extended to other conjugated high-molecular polymers, thereby it is proposed as a general method for rational design of efficient seawater U(VI) extraction materials. [Display omitted] • CPAO can show excellent uranium adsorption performance in the weak alkaline environment of seawater. • CPAO has excellent stability and mechanical properties. • Synthesis of CPAO with Different Conjugated Structures. • CPAO has excellent photothermal effect, which can accelerate the thermal motion of surrounding ions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Selective adsorption of Cr3+ at the interface driven by the Fe3+-O-Ti4+ bonds. • The internal electron cloud density of Fe 3 O 4 is enhanced by ion doping and increases adsorption sites for Cr3+ at the interface. • The increased defects are obtained by constructing built-in electric field with ion-doped Fe 3 O 4. • Surface defects of TiO 2 accelerate electron transferring in the Fe3+-O-Ti4+ bonds and enhance the selectivity of adsorption. Selective adsorbents for the sorted recovery of ppm-level mixed cation solutions have been identified as a promising strategy. However, the current design of adsorbents is still abided by the modification or enhancement for the common adsorption sites. The focus on other adsorption interfaces with innovative designs is rarely. In this paper, we report an adsorbent for shell-core type Fe 3 O 4 @TiO 2 grown on the edge of montmorillonite. The selective adsorption of Cr3+ was accomplish by constructing an Fe 3 O 4 (3 1 1)-TiO 2 (1 0 1) interface through long-range bonds of Fe3+-O-Ti4+, which was in accordance with the Freundlich model. An adsorption amount of Cr3+ was obtained as 194.36 mg/g in the presence of (Cu2+, Sn4+)-Fe3+-O-Ti4+, which was much higher than that of the strongest interference Ni2+ (47.68 mg/g) on the same site, by virtue of promoting electron transport on the Fe 3 O 4 surface through ion doping. Simultaneously, the more active TiO 2 surface structure was enabled by polycrystalline surface distortion, which was triggered by the built-in electric field. The increased electron cloud density within Fe 3 O 4 provided electrons, accelerated the enrichment of interfacial holes and endowed sufficient selective sites for restraining Cr3+. This work may provide some insight into the application of interfacial adsorbents for classified collection. [ABSTRACT FROM AUTHOR]

Abstract: We study the effect of the nonlinearity on electrons transmission properties in a double barriers structure GaAs/Al x Ga1− x As superlattices. The nonlinearity is introduced as an effective potential in the Schrödinger equation and translates the electronic Colombian repulsion. We have used the transfer matrix formalism and the plane wave functions approximation to solve numerically the equation and calculate the electronic transmission coefficient. We have shown the occurrence of two allowed states within the same well instead of a single, translating the presence of two resonant states at two different energies. The first allowed state intensity strongly decreases with increasing the nonlinear parameter, whereas the second one called the degeneracy state increases. Both the two states evolve towards higher resonances energies. [Copyright &y& Elsevier]

Adsorption of 5-fluorouracil (5-FU) and 2,4-dithio-5-fluorouracil (2,4-DT-5-FU) on Au(111) surface at low coverage is studied by using periodic-slab-density functional theory calculation. Isolated 5-FU molecule adsorbs preferentially at bridge site in a vertical configuration via NH group by forming the NH···Au nonconventional H-bond. The formation of the anchor AuO bond is not observed. Substitution of oxygen atoms of 5-FU with sulfur strongly influences the nature of adsorption and leads to the AuS anchor bond and the NH···Au nonconventional H-bond of single 2,4-DT-5-FU molecule on Au(111) surface. The adsorption site and orientation of 2,4-DT-5-FU molecule on the surface are similar to those of 5-FU. The metal-molecule coupling effects at asymmetric Au/S(NH)S/mol/CH/Au and Au/NH/mol/O/Au transport junctions and symmetric Au/S(NH)S/mol/mol/S(NH)S/Au and Au/O/mol/mol/O/Au transport junctions are also investigated. The electronic structure is analyzed in detail, and the obtained results are used for illustrating the electron transmission in metal-molecule-metal systems. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 [ABSTRACT FROM AUTHOR]

Copyright of Revue Francophone des Laboratoires is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This document describes the application of the syntax, semantic rules, and format of the Nomenclature for Properties and Units (NPU) terminology for coded dedicated kinds-of-property in the various subject fields of the clinical laboratory sciences. The document sums up considerations and reasoning by the Committee and Subcommittee on Nomenclature for Properties and Units (C-SC-NPU) and collects the experience with the system through some eight years of application in electronic health communication. Access to the NPU terminology in English is currently at , via the English download files from the Danish Release Centre under the National Board of Health. Updates to the terminology are usually presented once a month. [ABSTRACT FROM AUTHOR]

This document describes the application of the syntax, semantic rules and format of the NPU terminology for coded dedicated kinds-of-property in the various subject fields of the clinical laboratory sciences. The document sums up considerations and reasoning by the C-SC-NPU and collects the experience with the system through some 8 years of application in electronic health communication. Access to the NPU terminology in English is currently at www.labterm.dk, via the English download files from the Danish Release Centre under the National Board of Health. Updates to the terminology are usually presented once a month. [ABSTRACT FROM AUTHOR]

Abstract: We study theoretically the effects of short-range correlated disorder and applied bias on the nature of the transport properties in InAs/In x Ga1−x As superlattices. We consider layers having identical thickness where the (In) concentration x takes at random two different values with the additional constraint that barriers (wells) of one kind always appear in triple, thus forming random trimer barrier superlattices (RTBSL). We have numerically examined with the use of the exact Airy function formalism and the transfer-matrix method, the transmission properties across RTBSL. In the case of unbiased systems, we observed that the introduction of correlated disorder prevents the localization and causes delocalization states. This behavior is due to the trimer tunneling state originated for the basic cells of three singular barriers. In the case of biased systems, we see the decrease of the miniband width (reduction of transmission) until the complete disappearance for high values of V a. [Copyright &y& Elsevier]

numerical study is presented to investigate the role of solitons in the electronic states of double-stranded DNA (dsDNA) molecule in the metal/DNA/metal system. Based on tight-binding Hamiltonian model and within the framework of a generalized Green's function technique, we consider a ladder model for poly(dG)-poly(dC) DNA molecule containing M cells with four sites (two base pair sites and two backbone sites) in each cell. In the presence of a sublattice of solitons, our results show that the homogeneous soliton distributions induce the electronic states in the band gap of DNA molecule. In addition, the room temperature current-voltage characteristic of the system shows a linear and ohmic-like behaviour. [ABSTRACT FROM AUTHOR]

In this paper, based on the tight-binding Hamiltonian model and within the framework of a generalized Green's function technique, the electronic conduction through the poly(GACT)-poly(CTGA) DNA molecule in SWNT/DNA/SWNT structure has been numerically investigated. In a ladder model, we consider DNA as a planar molecule containing M cells and four further sites (two base pair sites and two backbone sites) in each cell, sandwiched between two semi-infinite single-walled carbon nanotubes (SWNT) as the electrodes. Having relied on Landauer formalism, we focussed on studying the current-voltage characteristics of DNA, the effect of the coupling strength of SWNT/DNA interface and the role of tube radius of nanotube contacts on the electronic transmission through the foregoing structure. Finally, a characteristic time was calculated for the electron transmission, which measures the delay caused by the tunnelling through the SWNT/DNA interface. The results clearly show that the calculated characteristic time and also the conductance of the system are sensitive to the coupling strength between DNA molecule and nanotube contacts. [ABSTRACT FROM AUTHOR]

Using a tight-binding model and a transfer-matrix technique, we numerically investigate the effects of the coupling strength and the role of solitons on the electronic transmission through a system in which trans-polyacetylene (trans-PA) molecule is sandwiched between two semi-infinite single-walled carbon nanotubes (SWNT). We rely on Landauer formalism as the basis for studying the conductance properties of this system. Our calculations show that the solitons play an important role in the response of this system causing a large enhancement in the conductance. Also our results suggest that the conductance is sensitive to the CNT/molecule coupling strength. [ABSTRACT FROM AUTHOR]