Determination of low-transverse shrinkage in slant fringe gratings of a cationic ring-opening volume hologram recording material

1997 ◽  
Author(s):  
David A. Waldman ◽  
H.-Y. S. Li
Keyword(s):  
Ring Opening ◽  
Hologram Recording ◽  
Volume Hologram ◽  
Recording Material ◽  
Transverse Shrinkage

Cationic ring-opening photopolymerimization methods for volume hologram recording

1996 ◽  
Author(s):  
David A. Waldman ◽  
Richard T. Ingwall ◽  
Pradepp K. Dhal ◽  
M. G. Horner ◽  
Eric S. Kolb ◽  
...  
Keyword(s):  
Ring Opening ◽  
Hologram Recording ◽  
Volume Hologram

Electrically switchable multiple volume hologram recording in polymer-dispersed liquid-crystal films

2009 ◽  
Vol 95 (20) ◽  
pp. 201105 ◽  
Author(s):  
Hongyue Gao ◽  
Haihui Pu ◽  
Bin Gao ◽  
Dejin Yin ◽  
Jianhua Liu ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Hologram Recording ◽  
Volume Hologram ◽  
Liquid Crystal Films ◽  
Polymer Dispersed Liquid Crystal ◽  
Crystal Films ◽  
Polymer Dispersed

scholarly journals New way of anionic ring-opening copolymerization of β-butyrolactone and ε-caprolactone: determination of the reaction course

2020 ◽  
Vol 27 (12) ◽  
Author(s):  
Zbigniew Grobelny ◽  
Justyna Jurek-Suliga ◽  
Sylwia Golba
Keyword(s):  
Ring Opening ◽  
Chemical Structure ◽  
Side Reactions ◽  
Complexing Agent ◽  
Critical Approach ◽  
Anionic Ring ◽  
Tetrahydrofuran Solution ◽  
End Group ◽  
C Nmr

Abstract Poly(ε-caprolactone)-block-poly(β-butyrolactone) copolymers were prepared in two-step synthesis. Firstly, poly(ε-caprolactone) (PCL) was obtained by anionic ring-opening polymerization of CL initiated with anhydrous KOH activated 12-crown-4 cation complexing agent. Reaction was carried out in tetrahydrofuran solution and argon atmosphere at room temperature. Then, β-butyrolactone (BL) and 18-crown-6 were added to the system, resulting in PCL-block-PBL copolymer, which contains after methylation hydroxyl starting group and methyl ester end group. The main product was contaminated with PCL and PBL homopolymers formed in a side reactions. 13C NMR technique was used for determination of chemical structure of polymers obtained. The course of the studied processes was proposed. MALDI-TOF technique was used to reveal the macromolecules’ architecture where several series were found. The identified series shown that mainly copolymeric macromolecules were formed with scare contribution of homopolymeric polybutyrolactone with trans-crotonate starting groups and polycaprolactone, which is congruent with the proposed reaction mechanism. Moreover, critical approach concerning previously reported PCL-block-PBL copolymer synthesis by use of NaH as initiator was also presented.

Study on Object Slight Displacement Measure Using Digital Image Hologram Method

2013 ◽  
Vol 347-350 ◽  
pp. 278-281
Author(s):  
Kun Yang ◽  
Peng Li ◽  
Yan Kun Tang ◽  
Yan Nan Zhai ◽  
Hui Zhang
Keyword(s):  
Digital Image ◽  
New Method ◽  
Hologram Recording ◽  
Double Exposure ◽  
Digital Hologram ◽  
Interference Fringes ◽  
Recording Material ◽  
Experimental Effect ◽  
Exposure Method ◽  
Slight Displacement

Digital image hologram and double exposure method is used to measure displacement of an object in this paper, the intensity of object light has been increased effectively, the contrast of interference fringes has been improved, clear interference fringes has been gotten. A new method has been proposed that CCD and EALCD are applied in order to record the digital hologram and interference fringes, the drawback is avoided successfully that fixing, relocation and nonlinear recording of traditional hologram recording material are. Better experimental effect is achieved.

scholarly journals Genetic and Biochemical Characterization of a Novel Monoterpene ɛ-Lactone Hydrolase from Rhodococcus erythropolis DCL14

2001 ◽  
Vol 67 (2) ◽  
pp. 733-741 ◽  
Author(s):  
Cécile J. B van der Vlugt-Bergmans ◽  
Mariët J. van der Werf
Keyword(s):  
Ring Opening ◽  
Biochemical Characterization ◽  
Rhodococcus Erythropolis ◽  
Open Reading Frames ◽  
Apparent Homogeneity ◽  
Terminal Amino ◽  
Acyl Coenzyme A ◽  
Reading Frames

ABSTRACT A monoterpene ɛ-lactone hydrolase (MLH) from Rhodococcus erythropolis DCL14, catalyzing the ring opening of lactones which are formed during degradation of several monocyclic monoterpenes, including carvone and menthol, was purified to apparent homogeneity. It is a monomeric enzyme of 31 kDa that is active with (4R)-4-isopropenyl-7-methyl-2-oxo-oxepanone and (6R)-6-isopropenyl-3-methyl-2-oxo-oxepanone, lactones derived from (4R)-dihydrocarvone, and 7-isopropyl-4-methyl-2-oxo-oxepanone, the lactone derived from menthone. Both enantiomers of 4-, 5-, 6-, and 7-methyl-2-oxo-oxepanone were converted at equal rates, suggesting that the enzyme is not stereoselective. Maximal enzyme activity was measured at pH 9.5 and 30°C. Determination of the N-terminal amino acid sequence of purified MLH enabled cloning of the corresponding gene by a combination of PCR and colony screening. The gene, designated mlhB(monoterpene lactone hydrolysis), showed up to 43% similarity to members of the GDXG family of lipolytic enzymes. Sequencing of the adjacent regions revealed two other open reading frames, one encoding a protein with similarity to the short-chain dehydrogenase reductase family and the second encoding a protein with similarity to acyl coenzyme A dehydrogenases. Both enzymes are possibly also involved in the monoterpene degradation pathways of this microorganism.

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