Surgery is necessary for most patients who underwent benign tracheoesophageal fistula, regarding the poor prognosis of the conservative treatment. However, it is hard for patients who suffer the airway obstruction by stent piercing to undergo the operation due to the difficulty of endotracheal intubation. This article presents an extracorporeal membrane oxygenation (ECMO)-assisted surgery to remove the esophageal stent before the routine endotracheal intubation, which can help to perform the operation successfully. Case ReportA 43-year-old woman patient was admitted to our hospital because of postprandial choking cough and shortness of breath for 3 weeks. Six years ago, she received chemotherapy and cervical radiotherapy for B cell lymphoma. Two years ago, a mediastinal lymph node metastasis was found by positron emission tomography (PET)-computed tomography (CT), for which she received mediastinal radiotherapy. After radiotherapy, the patient presented dysphagia, and chest CT scan revealed the presence of esophageal stenosis. The symptoms were relieved after esophageal expansion treatment. The patient presented 1 year ago with choking cough after drinking fluid, and an esophageal fistula, which had a diameter less than 1 cm and located 1.5 cm superior to the tracheal carina, was found by CT scan. To relieve the symptoms, a self-expanding metal stent was implanted. About 3 weeks ago, the patient complained of postprandial choking cough and shortness of breath again. Cervical CT scan in our hospital revealed tracheal obstruction caused by the expanding upper part of esophageal stent compression. Part of the stent pierced into the tracheal cavity in the thoracic entrance level forming a new tracheoesophageal fistula with a diameter of 3 cm. And no heal was found in the original fistula (Fig. 1). The bronchofibroscopic result verified the CT finding. Surgery, including the stent removing, cervical esophagostomy externa, exclusion of the thoracic tracheoesophageal fistulas and Application of ECMO to the Treatment of Benign Double Tracheoesophageal Fistula: Report of a CaseLei Wang, MD, Xiao Ping Xu, MM, Hen Zhang, MM, and Shao Ming Zhang, MD, PhD This report presents the extracorporeal membrane oxygenation (ECMO)-assisted surgical as a treatment of benign double tracheoesophageal fistula. The patient was a 43-yearold woman who presented the airway obstruction for 3 weeks after the esophagus metal stent implantation for the tracheoesophageal fistula 1 year ago. The airway obstruction was due to the expansion and piercing of the metal stent through the upper part of the esophagus into the tracheal cavity. In view of the failure of endotracheal intubation, we finally used ECMO-assisted surgery to remove the stent. And at the same time, cervical esophagostomy externa, exclusion of the thoracic tracheoesophageal fistulas and gastrostomy were performed.

Nickel foam-based Ni-Mo alloy electrodes, Ni+Mo composite electrodes and Ni+Mo/Ni-Mo composite alloy electrodes were prepared by eletrodeposition, and the electrocatalytic characteristics for hydrogen evolution reaction (HER) in 30wt% KOH solution were investigated by cathode polarization curve and electrochemical impedance spectroscopy (EIS). The experimental results show that in comparison with nickel foam electrodes, these electrodes exhibit a lower overpotential, a higher exchange current density and a larger real surface area for HER. At 30°C and current density of 200 mA/cm2, the overpotentials of foam Ni electrodes, nickel foam-based Ni-Mo alloy electrodes, Ni+Mo composite electrodes, Ni+Mo/Ni-Mo electrodes are respectively 506, 252, 336, 202 mV. The nickel foam-based Ni+Mo/Ni-Mo composite alloy electrode had the highest HER electrocatalytic activity.

The billet of magnesium AZ31B was made by twin-screw rheo-cast, and the specimen cut from the rheo-cast billet and normal cast billet were compressed in Gleeble-3000 hot simulator. The deformation temperature was 300, 350, and the strain rates were 0.001~1s-1. The relationship among flow stress, deformation temperature and strain rates were analyzed. The variation of the microstructure was observed and compared after the specimen was hot compressed. The results show that the surface of the rheo-cast specimen is much more smooth than the normal cast specimen after the compression. The dynamic recrystallization had taken place during the compression and the recrystallized grain of rheo-cast sample is more tiny than normal cast specimen.

In this work, B (boron) was added into Sn-1.0Ag-0.5Cu (SAC105) solder alloy using mechanical alloying method in order to develop a new low-silver lead-free solder, Sn-1.0Ag-0.5Cu-xB, where B ranges from 0wt% to 0.2wt%. The melting characteristics, wettability, mechanical properties of welded joints, and microstructure of this solder were studied. The results showed that with adding B into SAC105 alloy, the melting point and melting range was not obviously changed. Although the wettability decreases with the B content increasing, the solder joints exhibited higher shear strength. As a result, the shear strength was the highest at the B content of 0.2wt%. For example, the shear strength of the Sn-1.0Ag-0.5Cu-0.2B solder was 35.12MPa, while that of the B free SAC105 solder was only 28.94MPa. Furthermore, adding B had a significant effect on grain refinement on the SAC105 solder . Observations on solder matrix and weld joints by SEM showed that the IMC thickness of solder joints with the addition of B was less than the SAC105 lead-free solder. Moreover, with the addition of B, the solder grains were refined obviously which had the effect of refining straitening, and the growing rate of brittle IMC in solder joint could be effectively reduced during soldering and aging process. Thus solder joint performance can be improved significantly.

The solidification characterization of K418 alloy powders prepared by argon atomization was studied, and thermal parameters of the alloy powder during solidification process were calculated. The results show that powder morphology is spherical shape, the average diameter of the powder is 55μm, the amount of less 100μm powder is about 90 percent, the solidification microstructure of powders particle surface are dentrite and cellular structure. Decreasing the particle size, the microstructures of particle interior change from dentrite in major to cellular structures, and the structure is more uniformed. The length of secondary dentritic arm and the cooling rate as a function of K418 alloy powders size is established, the cooling rate increases with a decrease of the powder particle size, the cooling rate is in the range of 104K.S-1-106K.S-1.