Determination of Glass Transition Temperature (Tg) of Adhesive-Based Optical Fiber Components by In-Situ Bragg Grating Strain Sensing

2002 ◽  
Author(s):  
Keita Broadwater ◽  
Donald Barker ◽  
Yubing Yang
Keyword(s):  
Glass Transition ◽  
Thin Layers ◽  
Experimental Results ◽  
Strain Sensing ◽  
Glass Transition Region ◽  
Epoxy Adhesives ◽  
Mechanics Of Materials ◽  
Epoxy Material

This paper presents an in-situ evaluation technique that can be used to measure the Tg of thin layers. The studies presented in this paper were conducted on fiber optic connectors, but the results can be applied in general to ferrule-based components that use epoxy adhesives. This paper demonstrates how a strain sensor can theoretically detect the glass transition response of the epoxy material using a simple mechanics of materials approach. Several experimental results are presented showing that there is adequate sensor discrimination to detect the glass transition region. The technique also clearly showed residual curing and small changes in the Tg of the epoxy as the ferrule samples were subjected to multiple thermal cycles. The experimental results also demonstrate that the measured Tg of the epoxy in thin layers is different that that measured in bulk samples.

In Situ Determination of Glass Transition Temperatures of Epoxy Adhesives in Structural Ceramic Assemblies

2011 ◽  
Vol 62 ◽  
pp. 107-116
Author(s):  
Valérie Nassiet ◽  
Bouchra Hassoune-Rhabbour ◽  
Yves Baziard
Keyword(s):  
Glass Transition ◽  
Thermomechanical Analysis ◽  
Epoxy Adhesive ◽  
Lap Joint ◽  
Scanning Calorimetry ◽  
Experimental Conditions ◽  
Single Lap Joint ◽  
Epoxy Adhesives

A method is described for measuring the glass transition temperature (Tg) of epoxy joints bonding ceramic (SiC) substrates. This method is based on the strain measure of a single-lap joint subjected to a temperature variation. The resulting displacement (d) is observed as a function of the temperature (T) by means of a contact strain gauge extensometer. Thus Tg value can be determined using (d-T) curves recorded. The influence of joint parameters (joint thickness and overlap length) and of other parameters such as the applied load and the surface state of substrates were studied for a structural epoxy adhesive showing different thermomechanical behaviours. The results show that it is possible, with appropriate experimental conditions, to measure Tg with this method and to find Tg values similar to those found by classical techniques such as the static thermomechanical analysis (TMA) and the differential scanning calorimetry (DSC). This method shows similarities with TMA, but it has the advantage to allow the thermomechanical analysis of adhesives without destructive sampling of joints.

scholarly journals Method for determination of temperature characteristics of the glass transition region of polymeric materials using dielectric analysis. Part 1. Description

2019 ◽  
pp. 28-31
Author(s):  
A. S. Ivanitsky ◽  
A. A. Kordo ◽  
L. I. Boyko ◽  
O. V. Tomchani
Keyword(s):  
Glass Transition ◽  
Composite Materials ◽  
Dynamic Mechanical Analysis ◽  
Transition Region ◽  
Polymeric Materials ◽  
Mechanical Analysis ◽  
Dielectric Analysis ◽  
Glass Transition Region ◽  
Temperature Characteristics

A method for determining the temperature characteristics of the glass transition region of polymer and polymer composite materials using dielectric analysis is proposed. The method is based on the similarity of the dielectric analysis with dynamic mechanical analysis.

scholarly journals Method for determining the temperature characteristics of the glass-transition region of polymeric materials using dielectric analysis. Part 2. Testing.

2019 ◽  
pp. 30-32
Author(s):  
A. S. Ivanitsky ◽  
A. A. Kordo ◽  
L. I. Boyko ◽  
O. V. Tomchani
Keyword(s):  
Glass Transition ◽  
Polymer Composites ◽  
Transition Region ◽  
Polymeric Materials ◽  
Experimental Results ◽  
Dielectric Analysis ◽  
Glass Transition Region ◽  
Temperature Characteristics

The paper presents specifi c features and experimental results of the procedure proposed in Part 1 (N3-4/2019) to determine temperature characterstics of glass-transition region of polymers and polymer composites using dielectric analysis.

In situ phase separation and flow behavior in the glass transition region

2010 ◽  
Vol 18 (6) ◽  
pp. 1235-1239 ◽  
Author(s):  
Dmitri V. Louzguine-Luzgin ◽  
Takeshi Wada ◽  
Hidemi Kato ◽  
John Perepezko ◽  
Akihisa Inoue
Keyword(s):  
Glass Transition ◽  
Phase Separation ◽  
Transition Region ◽  
Flow Behavior ◽  
Glass Transition Region

scholarly journals A novel algorithm for vertical soil layering by utilizing the CPT data

2021 ◽  
Author(s):  
Meho Saša Kovačević ◽  
Mario Bačić ◽  
Lovorka Librić ◽  
Petra Žužul ◽  
Kenneth Gavin ◽  
...  
Keyword(s):  
Soil Profile ◽  
Cost Effective ◽  
Test Site ◽  
Thin Layers ◽  
Cone Penetration ◽  
Soil Layering ◽  
The Cost ◽  
Soil Behaviour

Determination of the relevant soil stratigraphy is of the paramount importance for any geotechnical analysis. The cone penetration test (CPT) is the cost-effective, rapid, continuous, and reliable testing method for assessing soil layering and estimating in-situ mechanical properties of soil, and as such is especially useful for subsoil investigations along linear infrastructure networks, such as roads, highways, or railways. The design soil profile can be effectively determined using the CPT-based soil behaviour type (SBT) classification system. However, the soil profile consists of layers of various thickness and some layers can be only a few centimetres thick. Because the cone needs to penetrate to a certain depth to develop the cone resistance and to identify the presence of another layer, thin layers of soil cannot be properly detected. The soil layering algorithm, presented in this paper, merges these thin layers into the adjacent layers and thus overcomes the unreliable determination of the thin layers. The implementation of the proposed algorithm is demonstrated using a CPT carried out on the embankment test-site in north Croatia.

scholarly journals Influence of In-Situ Nanoprecipitation on Constant Load Deformation in the Glass Transition Region of a Cu60Zr30Ti10 Bulk Metallic Glass

2004 ◽  
Vol 45 (7) ◽  
pp. 2383-2388
Author(s):  
Hidemi Kato ◽  
Dmitri V. Louzguine ◽  
Akihisa Inoue ◽  
Hyoung Seop Kim ◽  
Ho-Sou Chen
Keyword(s):  
Glass Transition ◽  
Metallic Glass ◽  
Bulk Metallic Glass ◽  
Transition Region ◽  
Constant Load ◽  
Glass Transition Region

RADIO INTERFEROMETRY DEPTH SOUNDING: PART II—EXPERIMENTAL RESULTS

Geophysics ◽  
1973 ◽  
Vol 38 (3) ◽  
pp. 581-599 ◽  
Author(s):  
James R. Rossiter ◽  
Gerald A. LaTorraca ◽  
A. Peter Annan ◽  
David W. Strangway ◽  
Gene Simmons
Keyword(s):  
Loss Tangent ◽  
Field Tests ◽  
Thin Layers ◽  
Experimental Results ◽  
Scale Model ◽  
Radio Waves ◽  
Depth Sounding ◽  
Transmitting Antenna ◽  
Crude Estimate

In such highly resistive geologic environments as ice sheets, salt layers, and the moon’s surface, radio waves penetrate with little attenuation. The field strengths about a transmitting antenna placed on the surface of such an environment exhibit interference maxima and minima which are indicative of the in‐situ electrical properties and the presence of subsurface layering. Experimental results from an analog scale model and from field tests on two glaciers are interpreted on the basis of the theoretical results of Part I. If the upper layer is thick, the pattern is very simple and the dielectric constant of the layer can be easily determined. An upper bound on the loss tangent can be estimated. For thin layers, the depth can be determined if the loss tangent is less than about 0.10, and a crude estimate of scattering can be made.

INDIREKTE PAPIERCHROMATOGRAPHISCHE METHODE ZUR BESTIMMUNG DER HARNOESTROGENE

1961 ◽  
Vol 38 (4) ◽  
pp. 545-562 ◽  
Author(s):  
L. Kecskés ◽  
F. Mutschler ◽  
I. Glós ◽  
E. Thán ◽  
I. Farkas ◽  
...  
Keyword(s):  
Pregnant Women ◽  
Granulosa Cell ◽  
Iron Content ◽  
List Type ◽  
Granulosa Cell Tumour ◽  
Hydrolysis Of ◽  
Phenol Fraction ◽  
Qualitative Determination

ABSTRACT 1. An indirect paperchromatographic method is described for separating urinary oestrogens; this consists of the following steps: acidic hydrolysis, extraction with ether, dissociation of phenol-fractions with partition between the solvents. Previous purification of phenol fraction with the aid of paperchromatography. The elution of oestrogen containing fractions is followed by acetylation. Oestrogen acetate is isolated by re-chromatography. The chromatogram was developed after hydrolysis of the oestrogens 'in situ' on the paper. The quantity of oestrogens was determined indirectly, by means of an iron-reaction, after the elution of the iron content of the oestrogen spot, which was developed by the Jellinek-reaction. 2. The method described above is satisfactory for determining urinary oestrogen, 17β-oestradiol and oestriol, but could include 16-epioestriol and other oestrogenic metabolites. 3. The sensitivity of the method is 1.3–1.6 μg/24 hours. 4. The quantitative and qualitative determination of urinary oestrogens with the above mentioned method was performed in 50 pregnant and 9 non pregnant women, and also in 2 patients with granulosa cell tumour.

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