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Since 1990, the replantation of hands severed at multiple levels has been carried out successfully for 22 patients. In each case the motor and sensory functions of the hand were recovered satisfactorily. We suggest that such wounds should be named 'multi-level severances' and should be classified into five groups according to the wound localities. In order to shorten ischaemic time, debridement should be carried out simultaneously by several groups. The main technical points of the operation are: (1) The order of replantation for multiply severed fingers is that the most distant section should be reattached first, and then the more proximal part. (2) High quality blood vessel anastomosis must be ensured. (3) Avoid taking the blood vessels, nerves and tendons from severed region. (4) During the operation, care should be taken to ensure that the replanted fingers' segments are protected from collision and stretching. In the early stages following the operation correct functional exercise is very important.  相似文献   
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This paper describes a method to measure the product of Prepl Pwall correction factors for ionization chambers and presents our measured values of Prepl Pwall for Markus plane-parallel chambers in electron beams. It is shown that the measured values of Prepl Pwall can be fitted to an equation, Prepl Pwall = c1 + c2 R50 + c3 (R50)2, for Markus chambers at the new reference depth for electron beams (6 MeV < or = nominal energy E < or = 20 MeV). We also present our measured values of Prepl Pwall for NACP and Markus chambers in a water phantom irradiated in a 60Co beam.  相似文献   
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The present study reports the economic and sustainable syntheses of functional porous carbons for supercapacitor and CO2 capture applications. Lignin, a byproduct of pulp and paper industry, was successfully converted into a series of heteroatom‐doped porous carbons (LHPCs) through a hydrothermal carbonization followed by a chemical activating treatment. The prepared carbons include in the range of 2.5 to 5.6 wt% nitrogen and 54 wt% oxygen in its structure. All the prepared carbons exhibit micro‐ and mesoporous structures with a high surface area in the range of 1788 to 2957 m2 g?1. As‐prepared LHPCs as an active electrode material and CO2 adsorbents were investigated for supercapacitor and CO2 capture applications. Lignin‐derived heteroatom‐doped porous carbon 850 shows an outstanding gravimetric specific capacitance of 372 F g?1 and excellent cyclic stability over 30,000 cycles in 1 M KOH. Lignin‐derived heteroatom‐doped porous carbon 700 displays a remarkable CO2 capture capacity of up to 4.8 mmol g?1 (1 bar and 298 K). This study illustrates the effective transformation of a sustainable waste product into a highly functional carbon material for energy storage and CO2 separation applications.  相似文献   
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Although LiNi0.5Mn1.5O4 (LNMO) high‐voltage spinel is a promising candidate for a next generation cathode material, LNMO/graphite full cells experience severe capacity fading caused by degradation reactions at electrode/electrolyte interfaces and consequent active Li+ loss in the cells. In this study, it is first reported that in situ formation of a Ti–O enriched cathode/electrolyte interfacial (CEI) layer on a Ti‐substituted LiNi0.5Mn1.2Ti0.3O4 (LNMTO) spinel cathode effectively mitigates electrolyte oxidation and transition metal dissolution, which improves the Coulombic efficiency and cycle life of LNMTO/graphite full cells. The Ti–O enriched CEI layer is produced in situ during an initial cycling of LNMTO as a result of selective Mn and Ni dissolution at its surface, as evidenced by various surface characterizations using X‐ray photoelectron spectroscopy, transmission electron microscopy, time‐of‐flight secondary ion mass spectrometry, Raman spectroscopy, and synchrotron‐based soft X‐ray absorption spectroscopy. The Ti–O enriched CEI has an advantage over traditional LNMO powder coatings, namely the formation of conformal CEI without compromising electronic conduction pathways between cathode particles.  相似文献   
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