Guide to determination of exposure limits, recovery times and relaxation times in work measurement

1991 ◽  
Keyword(s):  
Relaxation Times ◽  
Exposure Limits ◽  
Work Measurement ◽  
Recovery Times

Determination of polarization relaxation times of atomic levels

2012 ◽  
Vol 47 (5) ◽  
pp. 222-224 ◽  
Author(s):  
G. G. Adonts ◽  
E. G. Kanetsyan ◽  
M. A. Arzakantsyan
Keyword(s):  
Relaxation Times

scholarly journals Single-sided NMR for the measurement of the degree of cross-linking and curing

2018 ◽  
Vol 7 (1) ◽  
pp. 21-30 ◽  
Author(s):  
Norbert Halmen ◽  
Christoph Kugler ◽  
Eduard Kraus ◽  
Benjamin Baudrit ◽  
Thomas Hochrein ◽  
...  
Keyword(s):  
Relaxation Times ◽  
Curing Kinetics ◽  
Cross Linking ◽  
Scanning Calorimetry ◽  
First Results ◽  
Non Destructive ◽  
Kinetics Of ◽  
Good Agreement

Abstract. The degree of cross-linking and curing is one of the most important values concerning the quality of cross-linked polyethylene (PE-X) and the functionality of adhesives and resin-based components. Up to now, the measurement of this property has mostly been time-consuming and usually destructive. Within the shown work the feasibility of single-sided nuclear magnetic resonance (NMR) for the non-destructive determination of the degree of cross-linking and curing as process monitoring was investigated. First results indicate the possibility of distinguishing between PE-X samples with different degrees of cross-linking. The homogeneity of the samples and the curing kinetics of adhesives can also be monitored. The measurements show good agreement with reference tests (wet chemical analysis, differential scanning calorimetry, dielectric analysis). Furthermore, the influence of sample temperature on the characteristic relaxation times can be observed.

scholarly journals Multimedijski pristup određivanju graničnih vrijednosti elemenata životne sredine sa aspekta uticaja na zdravlje sportista // Multimedia Approach to Determination of Environmental Exposure Limits From the Aspect of Impact on the Health of Sportsmen

2014 ◽  
Vol 8 (2) ◽  
Author(s):  
Veljko Đukić ◽  
Cvijetin Živanović
Keyword(s):  
Environmental Exposure ◽  
Exposure Limits

Analizirani su nedostaci današnjeg monomedijskog pristupa određivanja graničnih koncentracija zagađenja medija životne sredine (vazduh, voda, hrana) sa aspekta uticaja na zdravlje sportista. Na primjeru zagađenja živom u dva geografska područja pokazana je nekonzistentnost i neekonomičnost ocjene ugroženosti sportista ako su granične vrijednosti donešene u postupku za svaki medij posebno, a na primjeru zagađenja vazduha, vode i hrane fenolom dokazuje se da se u različitim područjima mogu primjenjivati različite granične koncentracije za istu materiju u istom mediju uz primjenu multimedijskog pristupa određivanju graničnih vrijednosti.

Investigation of Rotational Relaxation by Double Resonance and Stark Switch Techniques

1980 ◽  
Vol 35 (8) ◽  
pp. 832-840
Author(s):  
W. Schrepp ◽  
H. Dreizler ◽  
A. Guarnieri
Keyword(s):  
Double Resonance ◽  
Relaxation Times ◽  
Experimental Methods ◽  
Rotational Relaxation ◽  
Triple Resonance ◽  
Static Electric Field ◽  
First Order ◽  
Four Levels ◽  
Relative Change

Abstract For the four rotational levels JK₋K₊ = 101, 110,212 and 221 of ethylene oxide all possible four level double resonance experiments for dipole allowed transitions have been performed to investigate collisional effects and to determine the relative change of signal intensity, η = ⊿I/I, due to high power pump radiation. The T1 and T2-relaxation times have been measured for all dipole allowed transitions within these four levels. A combination of the data obtained from both experimental methods allows the determination of rate and bath constants taking into account only first order dipolar transitions. No further restrictions have been used. This approximation is supported by a triple resonance experiment. In addition to the pure gas investigation in the absence of external fields, rotational relaxation has been studied in the presence of a static electric field and in a mixture with hydrogen.

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