A Self-Supported High-Entropy Metallic Glass with a Nanosponge Architecture for Efficient Hydrogen Evolution under Alkaline and Acidic Conditions

Developing highly efficient and durable electrocatalysts for hydrogen evolution reaction (HER) under both alkaline and acidic media is crucial for the future development of a hydrogen economy. However, state-of-the-art high-performance electrocatalysts recently developed are based on carbon carriers mediated by binding noble elements and their complicated processing methods are a major impediment to commercialization. Here, inspired by the high-entropy alloy concept with its inherent multinary nature and using a glassy alloy design with its chemical homogeneity and tunability, we present a scalable strategy to alloy five equiatomic elements, PdPtCuNiP, into a high-entropy metallic glass (HEMG) for HER in both alkaline and acidic conditions. Surface dealloying of the HEMG creates a nanosponge-like architecture with nanopores and embedded nanocrystals that provides abundant active sites to achieve outstanding HER activity. The obtained overpotentials at a current density of 10 mA cm⁻² are 32 and 62 mV in 1.0 m KOH and 0.5 m H₂SO₄ solutions, respectively, outperforming most currently available electrocatalysts. Density functional theory reveals that a lattice distortion and the chemical complexity of the nanocrystals lead to a strong synergistic effect on the electronic structure that further stabilizes hydrogen proton adsorption/desorption. This HEMG strategy establishes a new paradigm for designing compositionally complex alloys for electrochemical reactions.     

Glycotechnology for decontamination of biological agents: a model study using ricin and biotin-tagged synthetic glycopolymers

Two types of biotin-tagged glycopolymers carrying lactose or glucose in clusters along the polyacrylamide backbone were prepared and subjected to decontamination analyses with the plant toxin ricin. A buffer solution containing the toxin was treated with one glycopolymer followed by streptavidin-magnetic particles. Supernatant solutions were analyzed with surface plasmon resonance and capillary electrophoresis, and revealed that the lactose glycopolymer "captured" this toxin more effectively than the glucose polymer. Free toxin was not detectable in the supernatant after treatment with the glycopolymer and magnetic particles; >99% decontamination was achieved for this potentially fatal biological toxin.     

Influencing biophysical properties of fibrin with buffer solutions

Fibrin has been proposed as cell scaffold for numerous tissue engineering applications. While most of the studies have focused on fibrinogen and thrombin, other components of fibrin can also affect its properties. The present study aimed to evaluate the effects of buffer solution composition on fibrin biophysical properties. Fibrin scaffolds were synthesized with different calcium, chloride, and factor XIII (FXIII) final concentrations. Light transmission was determined as a relative, semi-quantitative estimator of fiber structure differences, and two compositions, resulting in translucent and opaque gels, were tested for mechanical and biological properties. Gels were seeded with mouse mesenchymal cells, C3H10T1/2, or bovine bone marrow-derived mesenchymal stromal cells and cultured up to 10 or 24 days, before cell number, morphology and distribution were evaluated. Calcium increased gel opacity (i.e., fiber thickness), while chloride and FXIII decreased it. Opaque gels displayed a fluid-like viscous behavior while translucent gels showed improved elastic properties. Both compositions supported survival of both cell types with opaque gels leading to better proliferation, but significant scaffold shrinkage after 17 days of culture. These results demonstrated that calcium, chloride, and FXIII modulate the biophysical properties of fibrin, and can be used to adjust mechanical and biological properties for tissue engineering applications.     

Women psychologists in academe: Mixed progress, unwarranted complacency.

This article reviews the characteristics of academic women in psychology. It also details what is known about women's participation in various academic roles and describes their successes in those roles. The article also discusses obstacles to women's success in psychology as a discipline and in academe more broadly. The article concludes with recommendations for the departments and institutions in which women work, as well as recommendations for APA and the field of psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Penetration Depth of Microwave into the Mixture of Goethite with Graphite Estimated by Permittivity and Conductivity

A study has been conducted to understand the penetration behavior of microwave into the mixture of goethite with carbon (C) aiming at providing an appropriate guidance to dehydrate the substances with hydroxides occasionally contained in industrial sludge. At first, it was observed that microwave could not sufficiently penetrate into the specimen with C/goethite molar ratios greater than 2, giving incomplete dehydration. To understand the penetration behavior of microwave, permittivity and conductivity were measured. Permittivity measurements were successfully made below 9 vol pct C. For carbon content greater than 8.56 vol pct C, the conductivity of the mixture abruptly increased by four orders of magnitude because of the occurrence of the conductivity percolation. Above 13.7 vol pct C close to an inflection point approximating 10 vol pct C, the mixture became sufficiently conductive. Transition from dielectric to conductive behavior occurred between 8.56 and 13.7 vol pct C. The Generalized Effective Medium approximation could satisfactorily express the variation of the conductivity values in the whole range of vol pct C measured. The penetration depth of microwave was determined by the above two measurements. It was found that penetration depth decreased with the increasing vol pct of C contained in the mixture specimen. Finally, guidance could be provided as for the blend ratio of C to treated material along with the size of a briquette or a pellet referring to the obtained relation between penetration depth and vol pct of C. Furthermore, it was proved that the numerical simulation was quite helpful to predict how microwave behaves in the mixture under given conditions.     

Hepatic preservation with histidine-tryptophan-ketoglutarate solution in living-related and cadaveric liver transplantation

The role of radiotherapy in the treatment of Hodgkin's disease and non-Hodgkin's lymphoma has changed considerably in the last few decades. Clinical observation of mainly unicentric pathogenesis with continuous expansion and subclinical involvement of adjoining regions of lymph nodes has resulted in the introduction of a large-field technique with total nodal irradiation (TNI) or total lymphatic irradiation (TLI). The introduction of polychemotherapy has led to further improvement in the cure rate and in considerations concerning using both methods and adapting them to the stage and risk. Today the combination of radiation and chemotherapy leads to a reduction in the amount of radiation required in the affected regions (involved field irradiation = IFI).     

A high-voltage polysilicon TFT with multigate structures

An approach is proposed for obtaining a high-voltage thin-film transistor (TFT) with multigate structure where polysilicon TFTs are connected in series. A basic principle for high-voltage operation has been investigated in detail through calculations based on a model describing log I_DS-V_GS characteristics observed in a single-gate polysilicon TFT. It has been found that off-state (V_GS<0) operation of the polysilicon TFT causes a large increase of breakdown voltage of the multigate TFT with the result that a nearly equal fraction of drain voltage is applied across the region around each elemental TFT. The breakdown voltage of drain of the fabricated multigate TFT which has five elemental TFTs has been elevated up to 80 V     

First-principles study on quantum-transport properties of single molecule depending on adsorption conditions

We present a first-principles electron-transport simulation within the framework of the density functional theory for a 1,4-benzenedithiol molecule suspended between semi-infinite Au electrodes. The transport properties are demonstrated under the several adsorption conditions. It is found that the conducting electrons have two types of resonant-tunneling transport properties with different responses to changes in adsorption conditions.     

Recent Researches on Microwave Processing for Materials and Environmental Technology in Our Group

Microwave processing has been taken into consideration for various purposes,not only for cooking,drying and enhancement of solution reaction kinetics but also various high temperature processes.In the presentation,selected research projects conducted in our group will be reported.The first topic is the microwave processing for recycling valuable metals from by-products originated in the iron and steel industries.We studied microwave application to handling of the pickling sludge,which occurs in stainless steel rolling process.Microwave use for dehydration and carbo-thermic reduction processes was attempted.Next,because Pb elution from the wasted funnel glass used for the cathod-ray tube is one of the serious environmental problems,microwave application to leaching process of Pb from a Pb-conatining glass was performed.The kinetic study of the acid dissolution was performed.Last topic is fabrication of filter material for burning particulate matter(PM)from diesel engine(Diesel Particulate Filter:DPF).Microwave rapid heating characteristics are applied to the cold start(ignition)condition of engine for prevention of PM emission.     

Formation of heterocyclic amine–amino acid adducts by heating in a model system

Although mutagenic and carcinogenic heterocyclic amines (HCAs) are known to be formed in cooked meat and fish, human HCA exposure and carcinogenic risk have not been elucidated in sufficient detail. In this work, we investigated the formations of HCA–amino acid adducts in a model system by using a liquid chromatography–mass spectrometry to elucidate another source of human HCA exposure. The 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) adduct with glycine was formed easily by heating at 200 °C within 5 min, which is probably based on the dehydration condensation of the amino group of PhIP and carboxyl group of glycine. PhIP and other HCAs such as 2-amino-3-methyl-3H-imidazo[4,5-f]quinolone, 2-amino-3,8-dimethylimidazo[4,5-f]-quinoxaline and 3-amino-1,4-dimethyl-5H-pyrido[3,4-b]indole, also bound with various amino acids by heating. Among these amino acids, proline tends to form adducts with HCAs, but serine, cysteine and lysine hardly bound with HCAs. These results provided a basic understanding of the formation of HCA adducts with amino acids during cooking.