TY  - JOUR
A1  - Zalden, Peter
A1  - Quirin, Florian
A1  - Schumacher, Mathias
A1  - Siegel, Jan
A1  - Wei, Shuai
A1  - Koc, Azize
A1  - Nicoul, Matthieu
A1  - Trigo, Mariano
A1  - Andreasson, Pererik
A1  - Enquist, Henrik
A1  - Shu, Michael J.
A1  - Pardini, Tommaso
A1  - Chollet, Matthieu
A1  - Zhu, Diling
A1  - Lemke, Henrik
A1  - Ronneberger, Ider
A1  - Larsson, Jörgen
A1  - Lindenberg, Aaron M.
A1  - Fischer, Henry E.
A1  - Hau-Riege, Stefan
A1  - Reis, David A.
A1  - Mazzarello, Riccardo
A1  - Wuttig, Matthias
A1  - Sokolowski-Tinten, Klaus
T1  - Femtosecond x-ray diffraction reveals a liquid-liquid phase transition in phase-change materials
JF  - Science
N2  - In phase-change memory devices, a material is cycled between glassy and crystalline states. The highly temperature-dependent kinetics of its crystallization process enables application in memory technology, but the transition has not been resolved on an atomic scale. Using femtosecond x-ray diffraction and ab initio computer simulations, we determined the time-dependent pair-correlation function of phase-change materials throughout the melt-quenching and crystallization process. We found a liquid-liquid phase transition in the phase-change materials Ag4In3Sb67Te26 and Ge15Sb85 at 660 and 610 kelvin, respectively. The transition is predominantly caused by the onset of Peierls distortions, the amplitude of which correlates with an increase of the apparent activation energy of diffusivity. This reveals a relationship between atomic structure and kinetics, enabling a systematic optimization of the memory-switching kinetics.
Y1  - 2019
U6  - https://doi.org/10.1126/science.aaw1773
SN  - 0036-8075
SN  - 1095-9203
VL  - 364
IS  - 6445
SP  - 1062
EP  - 1067
PB  - American Assoc. for the Advancement of Science
CY  - Washington, DC
ER  - 
TY  - JOUR
A1  - Zhang, Kai
A1  - Hu, Jiege
A1  - Yang, Shuai
A1  - Xu, Wei
A1  - Wang, Zhichao
A1  - Zhuang, Peiwen
A1  - Grossart, Hans-Peter
A1  - Luo, Zhuhua
T1  - Biodegradation of polyester polyurethane by the marine fungus Cladosporium halotolerans 6UPA1
JF  - Journal of hazardous materials
N2  - Lack of degradability and the accumulation of polymeric wastes increase the risk for the health of the environment. Recently, recycling of polymeric waste materials becomes increasingly important as raw materials for polymer synthesis are in short supply due to the rise in price and supply chain disruptions. As an important polymer, polyurethane (PU) is widely used in modern life, therefore, PU biodegradation is desirable to avoid its accumulation in the environment. In this study, we isolated a fungal strain Cladosporium halotolerans from the deep sea which can grow in mineral medium with a polyester PU (Impranil DLN) as a sole carbon source. Further, we demonstrate that it can degrade up to 80% of Impranil PU after 3 days of incubation at 28 celcius by breaking the carbonyl groups (1732 cm(-1)) and C-N-H bonds (1532 cm(-1) and 1247 cm(-1)) as confirmed by Fourier-transform infrared (FTIR) spectroscopy analysis. Gas chromatography-mass spectrometry (GC-MS) analysis revealed polyols and alkanes as PU degradation intermediates, indicating the hydrolysis of ester and urethane bonds. Esterase and urease activities were detected in 7 days-old cultures with PU as a carbon source. Transcriptome analysis showed a number of extracellular protein genes coding for enzymes such as cutinase, lipase, peroxidase and hydrophobic surface binding proteins A (HsbA) were expressed when cultivated on Impranil PU. The yeast two-hybrid assay revealed that the hydrophobic surface binding protein ChHsbA1 directly interacts with inducible esterases, ChLip1 (lipase) and ChCut1 (cutinase). Further, the KEGG pathway for "fatty acid degradation " was significantly enriched in Impranil PU inducible genes, indicating that the fungus may use the degradation intermediates to generate energy via this pathway. Taken together, our data indicates secretion of both esterase and hydrophobic surface binding proteins by C. halotolerans plays an important role in Impranil PU absorption and subsequent degradation. Our study provides a mechanistic insight into Impranil PU biodegradation by deep sea fungi and provides the basis for future development of biotechnological PU recycling.
KW  - Impranil PU degradation
KW  - Lipase
KW  - Cutinase
KW  - HsbA
KW  - Fatty acid degradation
Y1  - 2022
U6  - https://doi.org/10.1016/j.jhazmat.2022.129406
SN  - 0304-3894
SN  - 1873-3336
VL  - 437
PB  - Elsevier
CY  - Amsterdam
ER  -