Advanced Near-Infrared Moisture Analysis and Measurement in Ceramic Materials

2008 ◽  
pp. 35-41
Author(s):  
Ray Oberg
Keyword(s):  
Near Infrared ◽  
Ceramic Materials ◽  
Moisture Analysis

Moisture Analysis in Forage by Near-Infrared Reflectance Spectroscopy: Collaborative Study of Calibration Methodology

1991 ◽  
Vol 74 (2) ◽  
pp. 324-331
Author(s):  
William R Windham ◽  
Franklin E Barton
Keyword(s):  
Near Infrared ◽  
Collaborative Study ◽  
Calibration Method ◽  
Reflectance Spectroscopy ◽  
Near Infrared Reflectance ◽  
Moisture Concentration ◽  
Moisture Analysis ◽  
Relative Standard ◽  
Calibration Samples ◽  
Standard Deviations

Abstract Fifteen collaborating laboratories analyzed 16 forage samples including 3 blind duplicate pairs for moisture by air-oven (AO) method 7.007 (14th Ed.; 930.15, 15th Ed.) and nearinfrared reflectance spectroscopy (NIRS). Laboratories performed method 7.007 on 50 calibration samples and applied the NIRS calibration method Independently. NIRS moisture equations were used to predict the 16 test samples, and the values were compared to those for method 7.007. Moisture concentration of the test samples ranged from approximately 6 to 16%. Within-laboratory repeatability (sr) ranged from 0.10 to 0.18% and 0.16 to 0.39% for NIRS and method 7.007, respectively. Between-laboratory reproducibility (sR) ranged from 0.22 to 0.57 and 0.29 to 0.57 for NIRS and method 7.007, respectively. Repeatability relative standard deviations (RSDr) for the NIRS and AO methods ranged from 1.18 to 1.50% and 1.84 to 3.68%, respectively. The range in the average reproducibility relative standard deviations (RSDR) for the NIRS and AO methods were 1.29-7.49% and 3.64-6.66%, respectively. The NIRS method demonstrated consistently lower wlthln-laboratory RSDr agreement and between-laboratory variabilities equal to method 7.007. Thereby, we demonstrated that NIRS can be used as a standard method for the determination of 6-16% moisture In forages. The method has been adopted official first action by A0AC.

scholarly journals The application of NIR spectroscopy in moisture determining of vegetable seeds

2020 ◽  
Vol 38 (No. 2) ◽  
pp. 131-136
Author(s):  
Wojciech Poćwiardowski ◽  
Joanna Szulc ◽  
Grażyna Gozdecka
Keyword(s):  
Experimental Data ◽  
Least Squares ◽  
Partial Least Squares ◽  
Partial Least Squares Regression ◽  
Near Infrared ◽  
Nir Spectroscopy ◽  
Calibration Model ◽  
Least Squares Regression ◽  
Moisture Analysis ◽  
Non Destructive

The aim of the study was to elaborate a universal calibration for the near infrared (NIR) spectrophotometer to determine the moisture of various kinds of vegetable seeds. The research was conducted on the seeds of 5 types of vegetables – carrot, parsley, lettuce, radish and beetroot. For the spectra correlation with moisture values, the method of partial least squares regression (PLS) was used. The resulting qualitative indicators of a calibration model (R = 0.9968, Q = 0.8904) confirmed an excellent fit of the obtained calibration to the experimental data. As a result of the study, the possibilities of creating a calibration model for NIR spectrophotometer for non-destructive moisture analysis of various kinds of vegetable seeds was confirmed.<br /><br />

DWT-PLS Regression on Near-Infrared Spectra for Moisture Determination of Coal

2013 ◽  
Vol 827 ◽  
pp. 209-212
Author(s):  
Xiao Li Yang ◽  
Fan Wang ◽  
Wen Chao Wang ◽  
Yun Xiu Chen ◽  
Ji Shu Chen
Keyword(s):  
Bituminous Coal ◽  
Near Infrared ◽  
Principal Component ◽  
Discrete Wavelet ◽  
Moisture Determination ◽  
Least Squares Regression ◽  
Compression Performance ◽  
Moisture Analysis ◽  
Near Infrared Spectra ◽  
Compressed Data

We studied moisture determination in bituminous coal and lignitic coal samples using near-infrared (NIR) spectra. This research was developed by applying partial least squares regression (PLS) and discrete wavelet transform (DWT). Firstly, the NIR spectra were pre-processed by DWT for fitting and compression. Then, the compressed data were used to build regression model with PLS for moisture determination in coal samples. Compression performance at different resolution scales was investigated. Using the compressed data, PLS can obtain more accurate result than using raw spectra. The number of principal component in PLS model was investigated too. The results show DWT-PLS can obtain satisfactory determination performance for moisture analysis in bituminous coal and lignitic coal.

Moisture Analysis of Forage by Near Infrared Reflectance Spectroscopy: Preliminary Collaborative Study and Comparison Between Karl Fischer and Oven Drying Reference Methods

1988 ◽  
Vol 71 (2) ◽  
pp. 256-262
Author(s):  
William R Windham ◽  
Franklin E Barton ◽  
James A Robertson
Keyword(s):  
Standard Error ◽  
Near Infrared ◽  
Collaborative Study ◽  
Reflectance Spectroscopy ◽  
Infrared Reflectance ◽  
Near Infrared Reflectance Spectroscopy ◽  
Near Infrared Reflectance ◽  
Karl Fischer ◽  
Infrared Reflectance Spectroscopy ◽  
Moisture Analysis

Abstract A collaborative study of moisture analysis by neai infrared reflectance spectroscopy (NIRS) has been completed involving 5 laboratories and 20 forage samples. Near infrared reflectance spectroscopy calibrations for moisture were developed in the Associate Referee's laboratory from Karl Fischer (KF) and AOAC air oven (AO) (135°C for 2 h) moisture methods, respectively, and transferred to each collaborating laboratory's NIRS instrument. NIRS moisture data were validated with KF data from the Associate Referee's laboratory and AO data from each collaborating laboratory. The standard error of analysis of KF data by NIRS KF determination and AO data by NIRS AO determination ranged from 0.25 to 0.48% and from 0.74 to 1.88%, respectively. The standard errors between laboratories for NIRS KF and NIRS AO determinations were 0.2" and 0.39%, respectively. The standard error between moisture analyses by NIRS KF and NIRS AO calibrations, averaged across laboratories, was 0.42%. In addition, the standard error between laboratories for the AOAC AO method was 0.63%. The increase in standard error for the AOAC AO method was due to the random and systematic errors associated with the gravimetric techniques. The results indicate that NIRS analysis can accurately and precisely deterrr ine the moisture content of forages and forage crops because of th« very strong absorbance of water in the near infrared region.

Examination of Fracture Interfaces in Silicon Nitride

1975 ◽  
Vol 33 ◽  
pp. 60-61
Author(s):  
Nancy J. Tighe
Keyword(s):  
Silicon Nitride ◽  
Grain Boundary ◽  
Crack Growth ◽  
Subcritical Crack Growth ◽  
Slow Crack Growth ◽  
Ceramic Materials ◽  
Grain Boundary Sliding ◽  
Boundary Phase ◽  
Turbine Engines ◽  
Boundary Sliding

Silicon nitride is one of the ceramic materials being considered for the components in gas turbine engines which will be exposed to temperatures of 1000 to 1400°C. Test specimens from hot-pressed billets exhibit flexural strengths of approximately 50 MN/m2 at 1000°C. However, the strength degrades rapidly to less than 20 MN/m2 at 1400°C. The strength degradition is attributed to subcritical crack growth phenomena evidenced by a stress rate dependence of the flexural strength and the stress intensity factor. This phenomena is termed slow crack growth and is associated with the onset of plastic deformation at the crack tip. Lange attributed the subcritical crack growth tb a glassy silicate grain boundary phase which decreased in viscosity with increased temperature and permitted a form of grain boundary sliding to occur.

Stress-Induced Ordering in Y203-Stabilized Tetragonal Zr02

1985 ◽  
Vol 43 ◽  
pp. 222-223
Author(s):  
J. Y. Koo ◽  
M. P. Anderson
Keyword(s):  
Electron Diffraction ◽  
Ionic Conduction ◽  
Electron Diffraction Study ◽  
Ceramic Materials ◽  
Bright Field Image ◽  
Transformation Toughening ◽  
Ion Milling ◽  
Thin Foils ◽  
Carbon Coated ◽  
Convergent Beam

Tetragonal Zr02 has been used as a toughening phase in a large number of ceramic materials. In this system, complex diffraction phenomena have been observed and an understanding of the origin of the diffraction effects provides important information on the nature of transformation toughening, ionic conduction, and phase destabilization. This paper describes the results of an electron diffraction study of Y203-stabilized, tetragonal Zr02 polycrystals (Y-TZP).Thin foils from the bulk Y-TZP sample were prepared by careful grinding and cryo ion-milling. They were carbon coated and examined in a Philips 400T/FEG microscope. Fig. 1 shows a typical bright field image of the 100% tetragonal(t) Zr02. The tetragonal structure was identified by both bulk x-ray diffraction and convergent beam electron diffraction (Fig. 2. A local region within a t-Zr02 grain was subjected to an intense electron beam irradiation which caused partial martensitic transformation of the t-Zr02 to monoclinic(m) symmetry, Fig. 3 A.

Analytical and High-Resolution EM Study of Crystalline Phases formed at Metal-Ceramic Interface

1990 ◽  
Vol 48 (2) ◽  
pp. 426-427
Author(s):  
N. Merk ◽  
A. P. Tomsia ◽  
G. Thomas
Keyword(s):  
Cross Section ◽  
Dissimilar Materials ◽  
Ceramic Materials ◽  
Electron Micrograph ◽  
Scanning Electron Micrograph ◽  
Structural Applications ◽  
Metal Ceramic ◽  
The Subject ◽  
Ceramic Compounds ◽  
Scanning Electron

A recent development of new ceramic materials for structural applications involves the joining of ceramic compounds to metals. Due to the wetting problem, an interlayer material (brazing alloy) is generally used to achieve the bonding. The nature of the interfaces between such dissimilar materials is the subject of intensive studies and is of utmost importance to obtain a controlled microstructure at the discontinuities to satisfy the demanding properties for engineering applications . The brazing alloy is generally ductile and hence, does not readily fracture. It must also wett the ceramic with similar thermal expansion coefficient to avoid large stresses at joints. In the present work we study mullite-molybdenum composites using a brazing alloy for the weldment.A scanning electron micrograph from the cross section of the joining sequence studied here is presented in Fig. 1.

Analytical Electron Microscopy of Surface-Modified Ceramics

1985 ◽  
Vol 43 ◽  
pp. 276-279
Author(s):  
P. S. Sklad
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Theoretical Models ◽  
Ceramic Materials ◽  
Solute Concentration ◽  
Second Phase ◽  
Analytical Electron ◽  
Implantation Techniques ◽  
Lattice Damage ◽  
Surface Modified

Over the past several years, it has become increasingly evident that materials for proposed advanced energy systems will be required to operate at high temperatures and in aggressive environments. These constraints make structural ceramics attractive materials for these systems. However it is well known that the condition of the specimen surface of ceramic materials is often critical in controlling properties such as fracture toughness, oxidation resistance, and wear resistance. Ion implantation techniques offer the potential of overcoming some of the surface related limitations.While the effects of implantation on surface sensitive properties may be measured indpendently, it is important to understand the microstructural evolution leading to these changes. Analytical electron microscopy provides a useful tool for characterizing the microstructures produced in terms of solute concentration profiles, second phase formation, lattice damage, crystallinity of the implanted layer, and annealing behavior. Such analyses allow correlations to be made with theoretical models, property measurements, and results of complimentary techniques.

Interface structures in polycrystalline ceramic materials

1986 ◽  
Vol 44 ◽  
pp. 468-471
Author(s):  
K. J. Morrissey
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Physical And Mechanical Properties ◽  
High Resolution Electron Microscopy ◽  
Ceramic Materials ◽  
Polycrystalline Materials ◽  
Transmission Electron ◽  
Resolution Electron ◽  
Interface Structures

Grain boundaries and interfaces play an important role in determining both physical and mechanical properties of polycrystalline materials. To understand how the structure of interfaces can be controlled to optimize properties, it is necessary to understand and be able to predict their crystal chemistry. Transmission electron microscopy (TEM), analytical electron microscopy (AEM,), and high resolution electron microscopy (HREM) are essential tools for the characterization of the different types of interfaces which exist in ceramic systems. The purpose of this paper is to illustrate some specific areas in which understanding interface structure is important. Interfaces in sintered bodies, materials produced through phase transformation and electronic packaging are discussed.

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