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ObjectivesThe effects of early drain removal (EDR) on postoperative complications after pancreaticoduodenectomy (PD) remains to be investigated. This single-center retrospective cohort study was designed to explore the safety of EDR after PD.MethodsA total of 112 patients undergoing PD with drain fluid amylase (DFA) on postoperative day (POD) 1 and 3 ResultsNo statistical differences were found in primary outcomes, including Grade B/C postoperative pancreatic fistula (POPF) (Original cohort: 5.71% vs. 3.90%; P = 1.000; PSM cohort: 3.33% vs. 6.67%; P = 1.000), and total complications (Original cohort: 17.14% vs. 32.47%; P = 0.093; PSM cohort: 13.33% vs. 33.33%; P = 0.067). The EDR was associated with shorter in-hospital stay (Original cohort: 11 days vs. 15 days; P < 0.0001; PSM cohort: 11 days vs. 15 days; P < 0.0001).ConclusionsEDR on POD 3 is safe for patients undergoing PD with low risk of POPF.

To promote the practical application of electro-catalyst in vanadium flow battery, cell architecture based on catalyst coated membrane (CCM) is designed. CCM is prepared via spraying electro-catalyst tungsten trioxide/super activated carbon, which exhibits excellent electrochemical performance toward vanadium redox couples, on both sides of the membrane. Results show that the use of CCM structure reduces the charge transfer impedance of the cell, and thus improves the energy efficiency and the power density remarkably. The voltage efficiency and energy efficiency reach as high as 85.9% and 81.2%, respectively, much higher than that using the traditional cell structure (81.3% and 76.9%) at 120 mA cm−2. No loss in efficiency after 300 cycles indicates the favorable cycle stability of CCM. Therefore, CCM can be used as a promising vanadium flow battery structure for enhanced efficiency and power density.

A novel carbon paper electrode coated with supported tungsten trioxide is developed to improve the carbon fiber's electrochemical performance toward the vanadium redox couples. Super activated carbon supported tungsten trioxide (WO3/SAC) is prepared via an impregnation method and characterized by X-ray diffraction and scanning electron microscopy. The electrochemical performance of the prepared electrode is evaluated with cyclic voltammetry and electrochemical impedance spectroscopy. Results show that WO3/SAC exhibits excellent electro-catalytic activity and kinetic reversibility toward the vanadium redox couples. By adding the WO3/SAC, the charge transfer resistances for both the positive and the negative reactions are significantly reduced. Using as prepared electrodes, the columbic efficiency (CE), voltage efficiency (VE) and energy efficiency (EE) of the vanadium redox flow battery at 50 mA cm(-2) are 94.5%, 85.2% and 80.5%, respectively, which are much higher than that of the cell assembled with pristine carbon paper electrodes. (C) 2012 Elsevier B.V. All rights reserved.

Based on the impact mechanism and fluid wedge effect of the high-pressure fluid jet, a new approach to raw salt comminution has been worked out. The fluid jet comminution process has a unique characteristic of providing a fine appearance for the product particle as well as a high washing efficiency. Dissolution of raw salt and loss of product are avoided owing to saturated sodium chloride solution used as high-pressure medium. Compared with mechanical comminution, the product processed by this technique has higher quality and better appearance. The working condition is also improved since the comminution is operated under wet conditions. Also, this approach has the potential to be used to comminute the thermally sensitive, inflammable and explosive materials.