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Abstract The accelerated degradation test (ADT) is an efficient tool for assessing the lifetime information of highly reliable products. However, conducting an ADT is very expensive. Therefore, how to conduct a cost‐constrained ADT plan is a great challenging issue for reliability analysts. By taking the experimental cost into consideration, this paper proposes a semi‐analytical procedure to determine the total sample size, testing stress levels, the measurement frequencies, and the number of measurements (within a degradation path) globally under a class of exponential dispersion degradation models. The proposed method is also extended to determine the global planning of a three‐level compromise plan. The advantage of the proposed method not only provides better design insights for conducting an ADT plan, but also provides an efficient algorithm to obtain a cost‐constrained ADT plan, compared with conventional optimal plans by grid search algorithms.
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Cyclopentannulation and cyclodehydrogenation of isomerically pure 5,11-dibromo-anthradithiophenes leading to contorted aromatics
Isomerically pure 5,11-dibromo-2,8-dihexylanthra[2,3- b :76- b ′]dithiophene, a brominated analog of anthracenedithiophene (ADT), was prepared and utilized for a palladium catalyzed cyclopentannulation reaction with 3,3′-dimethoxy-phenylacetylene to give cyclopentannulated ADT (CP-ADTs). A further Scholl cyclodehydrogenation reaction gave contorted aromatics with large splay angles, low optical gaps, and low LUMOs.
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- PAR ID:
- 10093224
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 54
- Issue:
- 100
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 14140 to 14143
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c8cc07327a
