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Abstract: Porous carbons with large surface areas and pore volumes, as well as relatively uniform micropore texture were prepared by CO2 activation of ordered porous carbon CMK-1 for hydrogen storage. Both activation temperature and time were studied. The structure and texture changes in the carbons were investigated by using XRD and nitrogen sorption. Under the optimum condition that treating with CO2 at 950°C for 6h, a high H2 uptake of 2.19wt% was obtained at 77K and 1bar. The capacity is almost twice that of CMK-1 and higher than that of the reported porous carbons synthesized by silica templates. The pores smaller than 1nm were confirmed to be the most efficient for hydrogen sorption. Besides, high efficiency of surface areas and micropores were got for the H2 uptake at 77K and 1bar. [Copyright &y& Elsevier]

Covalent organic framework (COF) membranes with tunable ordered channels and free organic groups hold great promise in molecular separations owing to the synergy of physical and chemical microenvironments. Herein, we develop a defect engineering strategy to fabricate COF membranes for efficient CO 2 separation. Abundant amino groups are in situ generated on the COF nanosheets arising from the missing-linker defects during the reactive assembly of amine monomer and mixed aldehyde monomers. The COF nanosheets are assembled to fabricate COF membranes. Amino groups, as the CO 2 facilitated transport carriers, along with ordered channels endow COF membrane with high CO 2 permeances exceeding 300 GPU and excellent separation selectivity of 80 for CO 2 /N 2 , and 54 for CO 2 /CH 4 mixed gas under humidified state. Our defect engineering strategy offers a facile approach to generating free organic functional groups in COF membranes and other organic framework membranes for diverse chemical separations., (© 2022 Wiley-VCH GmbH.)

Objective: To investigate the operative method and clinical efficacy of repairing fingertip defect with modified reverse homodigital artery island flap., Methods: From March 2000 to September 2006, 18 cases (24 fingers) of fingertip defect were treated, including 12 males and 6 females aged 18-53 years (mean 29 years). Defect was caused by crush injuries in 12 cases, by avulsion injury in 3 cases, by twist injury in 2 cases and by incised injury in 1 case. The time from injury to operation was 2-8 hours (mean 4 hours). The location were index fingers (3 fingers), middle fingers (4 fingers) and ring fingers (17 fingers). The defects of soft tissue were 1.9 cm x 1.7 cm to 2.4 cm x 1.9 cm in size, the reverse homodigital artery island flaps were from 2.0 cm x 1.5 cm to 2.5 cm x 2.0 cm in size. The donor site was repaired with dumped skin grafting (3 cases) and with skin grafting from medial area of planta pedis (15 cases)., Results: Skin flaps and skin grafting of all the 24 fingers survived after operation. All incisions and donor sites healed by first intention. Sixteen patients (22 fingers) were followed up for 1-5 years (mean 3.2 years).The appearance and function of the flaps were all satisfactory. Two-point discriminations of flaps ranged from 4.5 mm to 6.3 mm. According to the total active movement/total passive movement assessment criteria, the results were excellent in 20 fingers and good in 2 fingers; and the excellent and good rate was 100%. The circumference of donor site was 2.0-3.5 mm shorter than that of normal side. The two-point discriminations of donor site was 7.8-10.5 mm., Conclusion: Repairing defect of fingertip with modified reverse homodigital artery island flap can provide good texture and contour matching the recipient area, good function and little trauma at donor site.