Novel Σ-Δ-based Direct Digitizers for Single-Element Resistive Sensors with Considerations on Lead-Wire Compensation

Author(s):  
Tapabrata Sen ◽  
Anoop Chandrika Sreekantan ◽  
Siddhartha Sen
Keyword(s):  

Resistive sensors can be used in a single element, differential and bridge forms. Resistive sensors have wide applications in industries. When the resistive sensor is directly connected with the microcontroller large amount of error arises due to lead wire resistance and microcontroller port pin resistances. Here, an enhanced interfacing of single element resistive sensor with a microcontroller scheme is proposed to compensate the error due to lead wires and port pin resistances. This scheme follows three discharge cycles for the measurement of resistances of the resistive sensor. The time taken for each discharge cycle is noted. From the time taken for the three discharge cycles, the resistance of the resistive sensor is directly calculated. Since the resistances due to lead wires and internal port pin resistances are corrected, the unknown temperature measurement is done accurately


Author(s):  
Dennis Maher ◽  
David Joy ◽  
Peggy Mochel

A variety of standard specimens is needed in order to systematically investigate the instrumentation, specimen, data reduction and quantitation variables in electron energy-loss spectroscopy (EELS). Pure single element specimens (e.g. various forms of carbon) have received considerable attention to date but certain elements of interest cannot be prepared directly as thin films. Since studies of the first and second row elements in two- or multicomponent systems will be of considerable importance in microanalysis using EELS, there is a need for convenient standards containing these species. For many investigations a standard should contain the desired element, or elements, homogeneously dispersed through a suitable matrix and at an accurately known concentration. These conditions may be met by the technique of implantation.Silicon was chosen as the host lattice since its principal ionization energies, EL23 = 98 eV and Ek = 1843 eV, are well removed from the K-edges of most elements of major interest such as boron (Ek = 188 eV), carbon (Ek = 283 eV), nitrogen (Ek = 400 eV) and oxygen (Ek = 532 eV).


Author(s):  
L. T. Germinario

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.


2014 ◽  
Author(s):  
Matthew E. Harvazinski ◽  
Venkateswaran Sankaran ◽  
Douglas G. Talley
Keyword(s):  

2014 ◽  
Author(s):  
Cheng Huang ◽  
Rohan Gejji ◽  
William Anderson ◽  
Changjin Yoon ◽  
Venkateswaran Sankaran

2016 ◽  
Author(s):  
Alicia M. Cruz-Uribe ◽  
◽  
Maureen Feineman ◽  
Thomas Zack ◽  
Dorrit E. Jacob

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