Lithium sulfur battery (LSB) offers several advantages such as very high energy density, low-cost, and environmental-friendliness. However, it suffers from serious degradation of its reversible capacity because of the...Lithium sulfur battery (LSB) offers several advantages such as very high energy density, low-cost, and environmental-friendliness. However, it suffers from serious degradation of its reversible capacity because of the dissolution of reaction intermediates, lithium polysulfides, into the electrolyte. To solve this limitation, there are many studies using graphene-based materials due to their excellent mechanical strength and high conductivity. Compared with graphene, graphene oxide (GO) contains various oxygen functional groups, which enhance the reaction with lithium polysulfides. Here, we investigated the positive effect of using GO mixed with carbon black on the performance of cathode in LSB. We have observed a smaller drop of capacity in GO mixed sulfur cathode. We further demonstrate that the mechanistic origin of reversibility improvement, as confirmed through CV and Raman spectra, can be explained by the stabilization of sulfur in lithium polysulfide intermediates by oxygen functional groups of GO to prevent dissolution. Our findings suggest that the use of graphene oxide-based cathode is a promising route to significantly improve the reversibility of current LSB.展开更多
BACKGROUND Few studies have been conducted on sex differences in the incidence, pathophysiology, and prognosis of gastric cancer(GC).AIM To analyze the differences in GC characteristics according to sex in patients wh...BACKGROUND Few studies have been conducted on sex differences in the incidence, pathophysiology, and prognosis of gastric cancer(GC).AIM To analyze the differences in GC characteristics according to sex in patients who underwent surgical treatment for GC.METHODS A total of 2983 patients diagnosed with gastric adenocarcinoma who received surgical treatment at the Seoul National University Bundang Hospital between 2003 and 2017 were included.Baseline clinicopathological characteristics, histologic type of GC, overall and GC-specific survival rates, and associated risk factors were analyzed.RESULTS Among the 2983 patients, 2005(67.2%) and 978(32.8%) were males and females, respectively.The average age of the female group(59.36 years) was significantly younger than that of the male group(61.66 years;P < 0.001).Cancer of the gastric body(P < 0.001) and diffuse-type histology(P < 0.001) were more common in females than in males.This trend was more prominent in females younger than 60 years of age, with a significantly higher proportion of diffuse-type cancer than in the male group.Regardless of sex, diffuse-type GC was more common in younger patients, and the proportion of intestinal-type GC increased with age.The overall survival rate was significantly higher in females(P < 0.001).However, this difference disappeared for GC-specific survival(P = 0.168), except for the poor GC-specific survival rate in advanced-stage cancer(stage Ⅲ or above) in females(P = 0.045).The risk factors for GC-related mortality were older age, upper location of GC, and diffuse-or mixed-type histology.In terms of comorbidities, more males died from diseases other than GC, including other malignancies such as lung cancer, hepatocellular carcinoma, and pancreatic cancer, and respiratory diseases such as interstitial lung disease and chronic obstructive pulmonary disease, while there were relatively more cardiovascular or cerebrovascular deaths in females.CONCLUSION Sex-based differences in GC were observed in clinicopathological features, including age at diagnosis, tumor location, histologic type, survival rate, and comorbidities.展开更多
基金supported by the Core Technology Development Program for Next-Generation Energy Storage of the Research Institute for Solar and Sustainable Energies (RISE) at GISTthe DOST UPD ERDT Faculty Development Program
文摘Lithium sulfur battery (LSB) offers several advantages such as very high energy density, low-cost, and environmental-friendliness. However, it suffers from serious degradation of its reversible capacity because of the dissolution of reaction intermediates, lithium polysulfides, into the electrolyte. To solve this limitation, there are many studies using graphene-based materials due to their excellent mechanical strength and high conductivity. Compared with graphene, graphene oxide (GO) contains various oxygen functional groups, which enhance the reaction with lithium polysulfides. Here, we investigated the positive effect of using GO mixed with carbon black on the performance of cathode in LSB. We have observed a smaller drop of capacity in GO mixed sulfur cathode. We further demonstrate that the mechanistic origin of reversibility improvement, as confirmed through CV and Raman spectra, can be explained by the stabilization of sulfur in lithium polysulfide intermediates by oxygen functional groups of GO to prevent dissolution. Our findings suggest that the use of graphene oxide-based cathode is a promising route to significantly improve the reversibility of current LSB.
基金Supported by National Research Foundation of Korea
文摘BACKGROUND Few studies have been conducted on sex differences in the incidence, pathophysiology, and prognosis of gastric cancer(GC).AIM To analyze the differences in GC characteristics according to sex in patients who underwent surgical treatment for GC.METHODS A total of 2983 patients diagnosed with gastric adenocarcinoma who received surgical treatment at the Seoul National University Bundang Hospital between 2003 and 2017 were included.Baseline clinicopathological characteristics, histologic type of GC, overall and GC-specific survival rates, and associated risk factors were analyzed.RESULTS Among the 2983 patients, 2005(67.2%) and 978(32.8%) were males and females, respectively.The average age of the female group(59.36 years) was significantly younger than that of the male group(61.66 years;P < 0.001).Cancer of the gastric body(P < 0.001) and diffuse-type histology(P < 0.001) were more common in females than in males.This trend was more prominent in females younger than 60 years of age, with a significantly higher proportion of diffuse-type cancer than in the male group.Regardless of sex, diffuse-type GC was more common in younger patients, and the proportion of intestinal-type GC increased with age.The overall survival rate was significantly higher in females(P < 0.001).However, this difference disappeared for GC-specific survival(P = 0.168), except for the poor GC-specific survival rate in advanced-stage cancer(stage Ⅲ or above) in females(P = 0.045).The risk factors for GC-related mortality were older age, upper location of GC, and diffuse-or mixed-type histology.In terms of comorbidities, more males died from diseases other than GC, including other malignancies such as lung cancer, hepatocellular carcinoma, and pancreatic cancer, and respiratory diseases such as interstitial lung disease and chronic obstructive pulmonary disease, while there were relatively more cardiovascular or cerebrovascular deaths in females.CONCLUSION Sex-based differences in GC were observed in clinicopathological features, including age at diagnosis, tumor location, histologic type, survival rate, and comorbidities.
