Luminescent polymers are referred to as conjugated polymers, which are constructed by π-aromatic building blocks functioning as emitting units. But in recent years, it has been found that a few kinds of polymers only containing auxochromophores or unconventional chromophores such as aliphatic tertiary amine, carbonyl, ester, and amide demonstrate strong luminescence under proper conditions. Poly(amido amine) (PAMAM) dendrimers and hyperbranched poly(amido amine)s are the first reported and most investigated luminescent polymers containing unconventional chromophores. Lately, this kind of polymers have been extended to hyperbranched poly(amino ester)s (hb-PAEs), hyperbranched poly(ether amide)s (hb-PEAs), and polyurea dendrimers (PUREs) containing tertiary amine moieties. The luminogen of PAMAMs, hb-PAEs, hb-PEAs and PUREs is associated with the N-branched tertiary amine moiety and the oxidation of the tertiary amine is assigned to the emitting source. Meanwhile, some distinct polymers had been also reported to be luminescent. Poly[(maleic anhydride)-alt-(vinyl acetate)], polyisobutene succinic anhydrides, glycodynamer analogues of poly(acrylhydrazone)s and multiblock polymer derived by poly(trithiocarbonate) mediated reversible addition-fragmentation chain transfer (RAFT) polymerization of N-isopropyl-acrylamide. A common feature of these polymers is that only carbonyl and ester groups rather than tertiary amine are involved in the polymer structure. Aggregation of multiple carbonyl groups induced emission is usually adopted to explain the mechanism of the emission, and the interaction between carbonyl and phenyl groups was also used to explain the unconventional emission.
This retrospective, hospital-based study shows that the number of patients with Crohn's disease in China has steadily increased over a period of 14 years. Further population-based epidemiological studies specifically focusing on risk factors are needed. The diagnosis of Crohn's disease and therapeutic strategy require improvement.
Several coal-and oil shale-bearing basins are distributed in the Dunhua-Mishan Fault Zone in Northeast China, while there are certain differences in sedimentary association and occurrence characteristics between the deposited rocks. Based on the results of previous research on stratigraphic correlation, the depositional age of sediments in the Fushun Basin is the Paleogene-Eocene, in the Huadian Basin it is the Eocene-Oligocene, and in the Meihe Basin, the Eocene-Early Oligocene. In the Fushun Basin, huge thick coal seams were formed in the Guchengzi Formation, thick low-quality oil shale layers were distributed in the lower part of the Jijuntun Formation and thick high-quality oil shale layers were developed in the Upper Jijuntun Formation. In the Meihe Formation of the Meihe Basin, coal seams were deposited in both the Lower Coal-bearing Member and the Upper Coal-bearing Member, while oil shale layers were formed in the Middle Mudstone Member. In the Huadian Basin, thin highquality oil shale layers were deposited in the Oil Shale Member and thin coal seams were accumulated in the Carbonaceous Shale Member. Thick coal seams were mainly deposited in the swamp with abundant land plant supply during the initial tectonic subsidence stage of the Dunhua-Mishan Fault Zone in the warm and humid paleoclimate. Relatively high-quality oil shale layers were all formed in the deep lake during the maximum tectonic subsidence evolution stages of these three basins, and the organic matter sourced from algae. Oil shale in the Fushun and Meihe basins was deposited in the warm and humid paloeoclimate, while in the Huadian Basin the climate varied from wet to dry. Investigation showed the Dunhua-Mishan Fault Zone to have gone through two coal-forming stages and one oil shale-forming stage. Coal seams in the Fushun Basin and the lower part of the Meihe Basin accumulated in the Ypresian stage, while those in the Huadian Basin and the Pingchang Sun et al.
204upper part of the Meihe Basin were deposited in the Bartonian-Priabonian stage. In contrast, oil shale layers in these three basins were all mineralized in the Lutetian stage.
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