In this study, high current densities si.e., 0.9 A/cm2d have been obtained in a hydrogen/air polymer electrolyte fuel cell using nanoscale tungsten carbide as the anode catalyst and carbon supported platinum as the cathode catalyst under normal operating conditions of 80 °C and 3 atm. These results show a possibility of replacing precious metal anode catalysts with transition metal compounds fo...

A tungsten neopentylidene complex has been found to decompose to yield a heterochiral dimer that contains a W=W double bond and no bridging ligands. Decompositions of related bisalkoxide complexes also yield compounds that contain an "unsupported" W=W double bond, while a sample of [Mo(NAr)(CH2-t-Bu)(OC6F5)]2 has been found to be a homochiral species related to [W(NAr)(CH2-t-Bu)(OC6F5)]2.

Recent studies of rat mesenteric arteries using a wire myograph detected decreased Ca2+ and acetylcholine-induced relaxation responses. Preliminary experiments indicated the reduced responses were associated with the tungsten wire used in the myograph system. Compared with earlier observations, arteries mounted on aged 28-microm tungsten wire showed decreased maximal Ca2+-induced relaxation res...

The acidity and its effects on reactivity of Keggin-type heteropolycompounds were examined by catalytic probe reactions, microcalorimetry of ammonia sorption, and density functional quantum chemical calculations. Phosphotungstic, phosphomolybdic, silicotungstic, and silicomolybdic acids were used as model compounds. The specific rates of double-bond isomerization of both 1-butene and cis-2-bute...

J o a c h i m F u c h s u n d E r n s t P e t e r F l i n d t Institut für Anorganische Chemie der Freien Universität Berlin Z . Naturforsch. 34b, 412 -422 (1979); eingegangen am 28. November 1978 Properties, X r a y , Heptatungstate , Paratungstate A , Metatungstate Polytungstates are obtained b y the reaction of hydrated tungsten (VI) oxide with bases or salts after occasional addition of org...

The number of individuals exposed to high levels of tungsten is increasing, yet there is limited knowledge of the potential human health risks. Recently, a cohort of breast cancer patients was left with tungsten in their breasts following testing of a tungsten-based shield during intraoperative radiotherapy. While monitoring tungsten levels in the blood and urine of these patients, we utilized ...

High environmental tungsten levels were identified near the site of a childhood pre-B acute lymphoblastic leukemia cluster; however, a causal link between tungsten and leukemogenesis has not been established. The major site of tungsten deposition is bone, the site of B-cell development. In addition, our in vitro data suggest that developing B lymphocytes are susceptible to tungsten-induced DNA ...

For the first time, both X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES) techniques were applied in analysis of surface contamination of electrochemically etched Scanning Tunneling Microscope (STM) tungsten tips. Carbon monoxide, graphite, tungsten carbide and tungsten oxide were found as main surface contaminations of STM tungsten tips. The thickness of tungsten ox...

Tungsten powder mixed with an appropriate amount of nickel and iron powders is used as raw material to fabricate large-scale tungsten whisker-like structure. The morphology, microstructure and composition of the whisker-like tungsten are observed and tested by scanning electron microscope and FESEM, transmission electron microscopy, X-ray spectroscopy, and X-ray diffraction, respectively. The m...