A New Type of Maximum on the Limiting Current of the Reduction Wave of Phenacyl Sulfonium Ions

1970 ◽  
pp. 268-278
Author(s):  
Süe-Yuan Tang ◽  
P. Zuman
Keyword(s):  
Limiting Current ◽  
Reduction Wave ◽  
Sulfonium Ions ◽  
New Type

Phenylmercuric Compounds: A Review of Analytical Methods and a Proposed Polarographic Assay

1966 ◽  
Vol 49 (4) ◽  
pp. 840-850
Author(s):  
Ted M Hopes
Keyword(s):  
Analytical Methods ◽  
Test Solution ◽  
Borate Buffer ◽  
Limiting Current ◽  
Reduction Wave ◽  
Polarographic Method ◽  
Sensitive Test ◽  
Final Test ◽  
Base Solution

Abstract A polarographic method, using pH 10 borate buffer and 0.1M KCl as the base solution, has been applied to phenylmercuric compounds. The second reduction wave given by phenylmercuric compounds is easy to measure. The limiting current is controlled by the diffusion and is directly proportional to concentration between 8 and 40 μg/ml. A sensitive test for free Hg++ will detect 3.7 μg/ml in the final test solution. The polarographic method is more specific, sensitive, and accurate than existing methods which are reviewed here. It is recommended that the method be applied to various pharmaceuticals.

Study of YSZ Amperometric Oxygen Sensor with a Dense Barrier Layer

2007 ◽  
Vol 280-283 ◽  
pp. 431-434 ◽  
Author(s):  
Xing Shi ◽  
Yue Zhang
Keyword(s):  
Diffusion Barrier ◽  
Internal Combustion Engines ◽  
Oxygen Sensor ◽  
Composite Electrode ◽  
Low Cost ◽  
Limiting Current ◽  
Combustion Engines ◽  
Lean Burn ◽  
New Type ◽  
And Diffusion

A new type of amperometric oxygen sensor was developed by an approach of co-pressing and co-sintering YSZ solid electrolyte. A dense LSM+YSZ composite electrode which was used as both cathode and diffusion barrier. Pre-sintered composite and YSZ powders were dry-pressed together to form a sheet with dual-layer of LSM+YSZ/YSZ. The sheet was then sintered at 1450°C. The anode was made of Pt paste, which was printed on to the other side of YSZ. The experiment results showed that the oxygen sensor exhibited a quite low operating temperature. At 400°C, the limiting current appeared in the voltage from 0.7 to 1.2V and the limiting current was a good linear relationship with the oxygen concentration up to 10 %. The sensor has some excellent features such as a rapid response, no reference gas, simple configuration and low cost. Taken together with the chemical stability of the diffusion barrier, the sensor is suitable for the control of air-to-fuel ratio in lean-burn internal combustion engines.

Limiting Current Oxygen Sensors with LSF as Dense Diffusion Barrier

2007 ◽  
Vol 336-338 ◽  
pp. 417-419 ◽  
Author(s):  
Ling Wang ◽  
Fu Shen Li ◽  
Hui Zhu Zhou ◽  
Hui Xia ◽  
Mei Yang ◽  
...  
Keyword(s):  
Diffusion Barrier ◽  
Solid Electrolytes ◽  
Oxygen Sensor ◽  
Low Cost ◽  
Limiting Current ◽  
Long Term Stability ◽  
Oxygen Ion ◽  
New Type ◽  
Ion Conducting

A new type of limiting current oxygen sensor which uses yttria (8%mol) stabilized zirconia (YSZ) as oxygen ion conducting solid electrolytes and dense La0.8Sr0.2FeO3 (LSF) as diffusion barrier was developed successfully. The oxygen sensor shows excellent performance at oxygen concentrations range of from 0 to 21%. The advantages of the sensor are simple construction, low cost and potential long term stability.

The Microstructure of Shock-Synthesized Diamond

1967 ◽  
Vol 25 ◽  
pp. 324-325
Author(s):  
Lucien F. Trueb
Keyword(s):  
Single Crystals ◽  
Preferred Orientation ◽  
High Magnification ◽  
Texture Pattern ◽  
Shock Process ◽  
New Type ◽  
Diffraction Diagram

A new type of synthetic industrial diamond formed by an explosive shock process has been recently developed by the Du Pont Company. This material consists of a mixture of two basically different forms, as shown in Figure 1: relatively flat and compact aggregates of acicular crystallites, and single crystals in the form of irregular polyhedra with straight edges.Figure 2 is a high magnification micrograph typical for the fibrous aggregates; it shows that they are composed of bundles of crystallites 0.05-0.3 μ long and 0.02 μ. wide. The selected area diffraction diagram (insert in Figure 2) consists of a weak polycrystalline ring pattern and a strong texture pattern with arc reflections. The latter results from crystals having preferred orientation, which shows that in a given particle most fibrils have a similar orientation.

New type electron gun with electrostatic and electromagnetic lenses

1978 ◽  
Vol 36 (1) ◽  
pp. 62-63
Author(s):  
T. Ichinokawa ◽  
H. Maeda
Keyword(s):  
Electron Microscopy ◽  
Electron Beam ◽  
Optimum Condition ◽  
Bias Voltage ◽  
Electron Gun ◽  
Charge Effect ◽  
Micro Fabrication ◽  
Maximum Brightness ◽  
New Type ◽  
The Ideal

I. IntroductionThermionic electron gun with the Wehnelt grid is popularly used in the electron microscopy and electron beam micro-fabrication. It is well known that this gun could get the ideal brightness caluculated from the Lengumier and Richardson equations under the optimum condition. However, the design and ajustment to the optimum condition is not so easy. The gun has following properties with respect to the Wehnelt bias; (1) The maximum brightness is got only in the optimum bias. (2) In the larger bias than the optimum, the brightness decreases with increasing the bias voltage on account of the space charge effect. (3) In the smaller bias than the optimum, the brightness decreases with bias voltage on account of spreading of the cross over spot due to the aberrations of the electrostatic immersion lens.In the present experiment, a new type electron gun with the electrostatic and electromagnetic lens is designed, and its properties are examined experimentally.

A new type of defect structure in 124-superconducting oxide revealed by HREM

1991 ◽  
Vol 49 ◽  
pp. 1092-1093
Author(s):  
R. Sharma ◽  
B.L. Ramakrishna ◽  
N.N. Thadhani ◽  
D. Hianes ◽  
Z. Iqbal
Keyword(s):  
Shock Wave ◽  
Defect Structure ◽  
Neutron Radiation ◽  
Weak Links ◽  
Defect Structures ◽  
New Materials ◽  
New Type ◽  
Current Densities ◽  
Processing Techniques ◽  
Microstructural Studies

After materials with superconducting temperatures higher than liquid nitrogen have been prepared, more emphasis has been on increasing the current densities (Jc) of high Tc superconductors than finding new materials with higher transition temperatures. Different processing techniques i.e thin films, shock wave processing, neutron radiation etc. have been applied in order to increase Jc. Microstructural studies of compounds thus prepared have shown either a decrease in gram boundaries that act as weak-links or increase in defect structure that act as flux-pinning centers. We have studied shock wave synthesized Tl-Ba-Cu-O and shock wave processed Y-123 superconductors with somewhat different properties compared to those prepared by solid-state reaction. Here we report the defect structures observed in the shock-processed Y-124 superconductors.

ESEM - A multipurpose surface Electron Microscope

1986 ◽  
Vol 44 ◽  
pp. 632-633 ◽  
Author(s):  
G.D. Danilatos
Keyword(s):  
Electron Microscope ◽  
Room Temperature ◽  
Environmental Scanning ◽  
Gas Composition ◽  
Saturated Water Vapor ◽  
Surface Electron ◽  
Current State ◽  
Saturated Water ◽  
New Type ◽  
Temperature And Pressure

Over recent years a new type of electron microscope - the environmental scanning electron microscope (ESEM) - has been developed for the examination of specimen surfaces in the presence of gases. A detailed series of reports on the system has appeared elsewhere. A review summary of the current state and potential of the system is presented here.The gas composition, temperature and pressure can be varied in the specimen chamber of the ESEM. With air, the pressure can be up to one atmosphere (about 1000 mbar). Environments with fully saturated water vapor only at room temperature (20-30 mbar) can be easily maintained whilst liquid water or other solutions, together with uncoated specimens, can be imaged routinely during various applications.

Trial production of γ-type energy filtering TEM

1995 ◽  
Vol 53 ◽  
pp. 604-605
Author(s):  
Y. Taniguchi ◽  
E. Nakazawa ◽  
S. Taya
Keyword(s):  
Magnetic Energy ◽  
Electron Optics ◽  
Electron Microscopic ◽  
Mass Spectrometers ◽  
Ion Optics ◽  
Energy Filtering ◽  
New Information ◽  
New Type ◽  
Fringing Fields

Imaging energy filters can add new information to electron microscopic images with respect to energy-axis, so-called electron spectroscopic imaging (ESI). Recently, many good results have been reported using this imaging technique. ESI also allows high-contrast observation of unstained biological samples, becoming a trend of the field of morphology. We manufactured a new type of energy filter as a trial production. This energy filter consists of two magnets, and we call γ-filter since the trajectory of electrons shows ‘γ’-shape inside the filter. We evaluated the new energyγ-filter TEM with the γ-filter.Figure 1 shows schematic view of the electron optics of the γ-type energy filter. For the determination of the electron-optics of the γ-type energy filter, we used the TRIO (Third Order Ion Optics) program which has been developed for the design of high resolution mass spectrometers. The TRIO takes the extended fringing fields (EFF) into consideration. EFF makes it difficult to design magnetic energy filters with magnetic sector fields.

Development of imaging plate for a TEM and its characteristics

1989 ◽  
Vol 47 ◽  
pp. 100-101
Author(s):  
N. Mori ◽  
T. Oikawa ◽  
Y. Harada ◽  
J. Miyahara ◽  
T. Matsuo
Keyword(s):  
Dynamic Range ◽  
Protective Layer ◽  
High Sensitivity ◽  
Imaging Plate ◽  
Phosphor Layer ◽  
Imaging Device ◽  
X Ray Imaging ◽  
New Type ◽  
Basic Characteristics ◽  
Reading System

The Imaging Plate (IP) is a new type imaging device, which was developed for diagnostic x ray imaging. We have reported that usage of the IP for a TEM has many merits; those are high sensitivity, wide dynamic range, and good linearity. However in the previous report the reading system was prototype drum-type-scanner, and IP was also experimentally made, which phosphor layer was 50μm thick with no protective layer. So special care was needed to handle them, and they were used only to make sure the basic characteristics. In this article we report the result of newly developed reading, printing system and high resolution IP for practical use. We mainly discuss the characteristics of the IP here. (Precise performance concerned with the reader and other system are reported in the other article.)Fig.1 shows the schematic cross section of the IP. The IP consists of three parts; protective layer, phosphor layer and support.

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