FABRICATION AND CHARACTERIZATION OF TIPS FOR ELECTROCHEMICAL SCANNING-TUNNELING-MICROSCOPY

We report a new technique for preparing tips for electrochemical scanning tunneling microscopy (ECSTM) with particular consideration of its simplicity and reproducibility. In preparing scanning tunneling microscopy (STM) tips by electrochemical etching, w

INVESTIGATION OF METALLOPORPHYRIN MODIFIED HOPG AND GC ELECTRODES BY SCANNING TUNNELING MICROSCOPE

HOPG and GC electrode surface feature modified with Cobaltmethyltetraphenylorphyrins (CoTPP) was investigated by scanning tunneling microscope combined with cyclic voltammograms. The effect of electrode surface morphologie

IN-SITU SCANNING TUNNELING MICROSCOPIC STUDY OF NICKEL ELECTRODEPOSITION ON HOPG

The early stages of the electrodeposition of nickel on highly oriented pyrolytic graphite (HOPG) were investigated by in situ scanning tunnelling microscopy, scanning electron microscopy and electrochemical measurements. Experimental results showed that t

DIRECT OBSERVATION OF NATIVE AND UNFOLDED GLUCOSE-OXIDASE STRUCTURES BY SCANNING-TUNNELING-MICROSCOPY

Native and unfolded glucose oxidase (GOD) structures have been directly observed with scanning tunnelling microscopy (STM) for the first time. STM images show an opening butterfly-shaped pattern for the native GOD. When GOD molecules are extended on anodi

ELECTROCHEMICAL SCANNING-TUNNELING-MICROSCOPY

An ECSTM apparatus with an ideal tip using a homemade SSX-1A STM instrument has been constructed. STM and ECSTM tips were made by electrochemical etching and insulating with paraffin, silicon rubber or epoxy resin under an optical microscope. In situ imag

Study on the structure of C-phycocyanin in Spirulina platensis with scanning tunneling microscope

The C-phycocyanin (C-PC) trimmer was isolated from the blue-green alga Spirulina platensis, and scanning tunnelling microscope (STM) was used to investigate its structure, High resolution STM images of C-PC were obtained. From the STM images, it could be observed that the C-PC molecules were disk-like in shape and the subunits of C-PC arranged in ring-like pattern with a channel in the center. After filter treatment, the folding of the polypeptide chains could be. seen clearly. This is the first time to observe directly the topography of phycobiliprotein, and the results showed STM to be a powerful tool for the structural study of phycobiliproteins.

Research and development of catalytic processes for petroleum and natural gas conversions in the Dalian Institute of Chemical Physics

The Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences has a long history in the R&D of catalysts and catalytic processes for petroleum and natural gas conversions in China. In this paper, results and features of some commercialized petrochemical catalysts and processes as well as newly developed processes for natural gas conversion in the pilot-plant stage are described. (C) 1999 Elsevier Science B.V. All rights reserved.