Carbon-caged palladium catalysts supported on carbon nanofibers for proton exchange membrane fuel cells

Publication date: 25 November 2019Source: Journal of Industrial and Engineering Chemistry, Volume 79Author(s): Hyo Eun Bae, Yeong Don Park, Tae-Hyun Kim, Taeho Lim, Oh Joong KwonAbstractThe development of low-cost catalysts for the oxygen reduction reaction is an important step for the commercialization of proton-exchange membrane fuel cells. Pd is a robust catalytic material for this reaction and is considered as an alternative to Pt due to its similarity with Pt. However, since Pd is oxidized at a lower positive potential than Pt, it is less active and less stable than Pt in an oxygen reduction reaction. We developed a simple synthesis route for N-doped carbon-caged Pd catalysts supported on carbon nanofibers using Pd-polyaniline composites. Oxidative polymerization of aniline spontaneously produced Pd-polyaniline composites with the reduction of Pd ions. The subsequent heat treatment of Pd-polyaniline composites produced N-doped carbon-caged Pd catalysts, in which the polyaniline served as the source of the N-doped carbon cage. The catalytic activity and stability of the synthesized catalyst were dependent on the heat-treatment temperature and the synthesis method. The optimized catalyst heat-treated at 500 °C (Pd@NC/CNF500 (NDA, US)), which was synthesized with non-distilled aniline under ultrasound irradiation, exhibited higher catalytic activity and stability in oxygen reduction reaction than general Pd catalysts reported in literature. Pd@NC/CNF500 (NDA, US) s...
Source: Journal of Industrial and Engineering Chemistry - Category: Chemistry Source Type: research

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CONCLUSIONS: This survey provided a comprehensive update of the present cataract surgery practices in the Republic of Korea. The results emphasized the increasing use of premium intraocular lenses, optical biometry, and topical anesthesia. PMID: 31612656 [PubMed - in process]
Source: Korean Journal of Ophthalmology : KJO - Category: Opthalmology Tags: Korean J Ophthalmol Source Type: research
ConclusionThe occurrence of carotid plaques in asymptomatic individuals is underestimated by ultrasound compared to plaque assessment by CTA. Carotid plaque composition by CTA is different in individuals with and without carotid plaques by ultrasound.Key Points•The occurrence of carotid plaques by ultrasound was underestimated in 46% of participants who had plaques by carotid CTA.•Participants with carotid plaques by ultrasound had higher volumes of all plaque subtypes and a higher calcified plaque component as determined by carotid CTA compared to participants without carotid plaques by ultrasound.•A high c...
Source: European Radiology - Category: Radiology Source Type: research
ConclusionsThis work has demonstrated a significant correlation between the degree of lesion enhancement in CESM and malignancy. Quantitative analysis of enhancement levels in CESM can distinguish between invasive cancers and benign or in situ lesions.Key Points• There is a possibility of quantitative assessment of contrast enhancement in CESM.• Correlation between quantitative assessment of contrast enhancement in CESM and histopathology was observed.
Source: European Radiology - Category: Radiology Source Type: research
Publication date: September 2019Source: Chinese Medical Sciences Journal, Volume 34, Issue 3Author(s): Yingya Li, Liyan Duan, Fengli Chi, Kunming LiAbstractHere we report a case of heterotopic cornual pregnancy after in vitro fertilization who was diagnosed at 6 weeks after frozen embryos transfer. The heterotopic pregnancy was successfully terminated by transvaginal ultrasound-guided selective fetal reduction. At 38+1 weeks, she underwent a cesarean section and delivered a healthy 3300 g male infant with Apgar score of 10-10' evaluated at 1 min and 5 min.
Source: Chinese Medical Sciences Journal - Category: General Medicine Source Type: research
Publication date: Available online 15 October 2019Source: Annals of Medicine and SurgeryAuthor(s): Sardar Hassan Arif, Ayad Ahmad MohammedAbstractAbdomen cocoon is a rare disease in which a thick peritoneal membrane wraps the intestine causing the bowel loops to adhere to each other. It may be either primary(idiopathic) or secondary to other causes like previous abdominal surgery. Most patients present with abdominal pain and intestinal obstruction. The condition is usually diagnosed intraoperatively.Case 1A 30-year-old male patient presented with abdominal pain and bilious vomiting. The patient had similar previous attack...
Source: Annals of Medicine and Surgery - Category: General Medicine Source Type: research
Publication date: Available online 15 October 2019Source: Journal of Food Composition and AnalysisAuthor(s): Roberto RodriguezAbstractAn analytical method for extraction and quantitative determination of the main phenolic compounds (hydroxycinnamic acids and derivatives, anthocyanins and flavonols) in dry beans (Phaseolus vulgaris) is described. The best extraction conditions were: 100% sonication amplitude, 10.3 min extraction, 46% ethanol, 1.5 g dry bean flour and 30 mL of solvent. The developed method was validated in terms of accuracy and precision. Good linearity was obtained, with correlation coe...
Source: Journal of Food Composition and Analysis - Category: Food Science Source Type: research
Publication date: December 2019Source: Food Research International, Volume 126Author(s): Yanan Sun, Min Zhang, Bhesh Bhandari, Chao-hui YangAbstractThe synergistic impact of ultrasound and Nano-water retaining agent on the cryoprotective effect on crayfish during frozen storage was investigated. The samples soaked in water-retaining agent (WRA), ultrasonic 60 W treatment combined with water-retaining agent (WRA-US60W) and ultrasonic 80 W treatment combined with water-retaining agent (WRA-US80W) were frozen storage at −18 °C. The indices of frozen storage in 0, 7, 14, 21, 28, 35 and 42 days were measured. ...
Source: Food Research International - Category: Food Science Source Type: research
We report on a 13-year-old boy who presented with right iliac fossa pain associated with anorexia, tenderness, guarding and rebound tenderness. Abdominal ultrasound showed findings of acute appendicitis. However, laparoscopy revealed a wooden toothpick perforating MD and a hyperemic appendix. The FB was removed and laparoscopic diverticulectomy and appendectomy performed. Perforation of MD by a FB is a diagnostic challenge and it should be included in the differential diagnosis of acute abdomen in children.
Source: Journal of Pediatric Surgery Case Reports - Category: Surgery Source Type: research
ConclusionsTreatment guidelines aiming for complete ablation enhanced the effectiveness of MR-HIFU therapy. However, controlled trials should define the role of MR-HIFU in the management of uterine fibroids.
Source: European Journal of Radiology - Category: Radiology Source Type: research
Background The purpose of this study was to assess the objective and subjective outcomes of lower face volumetric (contour) asymmetry correction with isolated fat grafting in skeletally immature patients. Methods A prospective analysis was conducted of skeletally immature patients (n = 73) with craniofacial microsomia and Parry-Romberg syndrome who underwent isolated fat grafting (with no previous or concomitant bone surgery) using anatomical surgical principles (facial subunits and fat compartments) for the reconstruction of lower face volumetric asymmetry. Objective ultrasound and photogrammetric lower face symmetry...
Source: Annals of Plastic Surgery - Category: Cosmetic Surgery Tags: Head and Neck Surgery Source Type: research
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