Designed porosity in coordination materials often relies on highly ordered crystalline networks, which provide stability upon solvent removal. However, the requirement for crystallinity often impedes control of higher degrees of morphological versatility, or materials processing. Herein, we describe a supramolecular approach to the synthesis of amorphous polymer materials with controlled microporosity. The strategy entails the use of robust metal–organic polyhedra (MOPs) as porous monomers in the supramolecular polymerization reaction. Detailed analysis of the reaction mechanism of the MOPs with imidazole-based linkers revealed the polymerization to consist of three separate stages: nucleation, elongation, and cross-linking. By controlling the self-assembly pathways, we successfully tuned the resulting macroscopic form of the polymers, from spherical colloidal particles to colloidal gels with hierarchical porosity. The resulting materials display distinct microporous properties arising from the internal cavity of the MOPs. This synthetic approach could lead to the fabrication of soft, flexible materials with permanent porosity.
We designed an automatic system to measure body length, diameters and volume of a C. elegans worm. By using this system, mutants with an increased body volume exceeding 50% were isolated. Four of them are grossly normal in morphology and development, grow longer to be almost twice as big, and have weak egg-laying defects and extended lifespan.
This study deals with supercritical CO 2 extraction of astaxanthin from Haematococcus pluVialis with ethanol as an entrainer. The effects of pressure, temperature, CO 2 flow rate, and the existence of the entrainer concentration on the amount of total extract, the amount of astaxanthin extracted, and the astaxanthin content in the extract were studied. Extractions were carried out at the pressures of 20-55 MPa, temperatures of 313-353 K, CO 2 flow rates of 2-4 mL/min, and the ethanol entrainer concentrations of 1.67-7.5% (v/v). The amount of the total extract, astaxanthin extracted, and astaxanthin content in the extract increased with increasing temperature and pressure. With higher CO 2 flow rate, the amount of the total extract could be increased while the amount of astaxanthin extracted and the astaxanthin content in the extract almost did not change. By using ethanol as an entrainer, a higher amount of astaxanthin extracted (80.6%) could be obtained at moderate pressure and temperature, and with the same conditions, the addition of the ethanol entrainer could more than twice enhance the amount of astaxanthin extracted. Without the ethanol entrainer, the highest astaxanthin extracted and astaxanthin content in the extract were 77.9 and 12.3%, respectively, and were obtained at high pressure and temperature.
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