RIPENING OF SILVER NANOPARTICLES ON CARBON NANOTUBES

LIYING ZHU,GANHUA LU,SHUN MAO,JUNHONG CHEN,DMITRIY A. DIKIN,XINQI CHEN,로드니루오프 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2007 NANO Vol.2 No.3

An electrostatic-force-directed-assembly technique was used to coat multiwalled carbon nano-tubes (MWCNTs) with aerosol Ag nanoparticles produced from a mini-arc plasma source. The deposition of Ag nanoparticles onto CNTs was confirmed by transmission electron microscopy (TEM), high-resolution TEM, scanning electron microscopy, and X-ray photoelectron spectroscopy. Ripening of Ag nanoparticles on CNTs was observed via successive TEM imaging after heating the nanoparticle–nanotube hybrid structures in air to three different temperatures ranging from 100°C to 300°C. With temperatures at and above 200°C, the areal density of Ag nanoparticles decreased and the average particle size increased. In particular, migration and coalescence of Ag nanoparticles have been observed at this relatively low temperature, which suggests a van der Waals nanoparticle–nanotube interaction.

Simulation on the Process of Contact Erosion between Cohesionless Soils

Liying Chang,Qun Chen 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.8

To explore the mechanism of contact erosion, cohesionless soil layers subjected to a flow parallel to the interface were simulated using particle flow code (PFC). The calculation model with different particle size ratio D15/d85 from 1.84 to 6.88 between two soil layers was designed based on the experiment. The movement process of the particles during contact erosion was explored. The results show that, when one particle was eroded, it first moved up into bigger pores and then was carried out along the flow direction. A grain size transition zone gradually formed between two layers, where particles of two soil layers mixed. For numerical samples with particle size ratio D15/d85 larger than 4.0, the eroded particles could all be carried out by the flow, so the particle size ratio D15/d85 at the transition zone remained larger than 4.0 according to Terzaghi's particle retention criterion; thus, the erosion continued resulting in the increase in the flow velocity and the erosion rate.

Synthesis of fly ash-based microporous copper silicate for CO2 capture from humid flue gases

Liying Liu,Xudong Chen,Yushun Wang,Tao Du,Gang Li 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.3

Conventional microporous adsorbents suffer from CO2 adsorption capacity reduction due to the presence of water vapor in real flue gases. Therefore, development of low-cost moisture-insensitive adsorbents is of great significance. In the present work, microporous copper silicate was synthesized from waste fly ash for the first time. The synthesis conditions were further optimized to obtain copper silicates with high purities. The as-synthesized product was characterized in terms of structural morphology, chemical composition, and surface properties. The CO2 and H2O adsorption properties of the prepared copper silicate were also investigated by single-component isotherm measurements and dynamic CO2/H2O binary breakthrough experiments. The results show that the as-synthesized fly ash-based copper silicate exhibited excellent CO2 adsorption properties even in the presence of water vapor, thus demonstrating promising potential as a moisture-insensitive adsorbent for directly capturing CO2 from humid flue gases.

Cellulase Production from the Corn Stover Fraction Based on the Organ and Tissue

Hongzhang Chen,Qin He,Liying Liu 한국생물공학회 2011 Biotechnology and Bioprocess Engineering Vol.16 No.5

In this study, the biodegradation of fractionated corn stover in solid-state fermentation by Trichoderma reesei YG3 was investigated. Fractions of miscellaneous cells (MC) and fasciculi (FC) tissue from leaf, shell or core were separated using the combined pretreatment method of carding classification after steam explosion. The highest enzyme activities including the filter paper activity, endoglucanase,exoglucanase and β-glucosidase activities, weight loss rate of dry material and biodegradation rate were all observed in the MC tissue fraction from the leaf, which was more nutritious, while lowest activity was observed in the FC tissue fraction from the shell. The maximum filter paper activity and weight loss rate of the dry material were 4.56 and 1.89 times the minimum and the cellulose and hemicellulose biodegradation rates were 51.22 and 39.38%versus 23.85 and 26.51%, respectively. These variances maybe attributed to the heterogeneity of the component in the fractions. A higher weight loss rate corresponded to higher enzymatic activities, whereas cellulose biodegradation was not proportional to cellulase activities. Hemicellulose biodegradation was much slower than cellulose degradation. Here, we demonstrated the importance of fractionation in component biodegradation and utilization of straw.

Preparation of self‑supporting Co3S4/ S‑rGO film catalyst for efficient oxygen evolution reaction

Liang Chen,Liying Hu,Chenxi Xu,Lanyun Yang,Wei Wang,Junlin Huang,Minjie Zhou,Zhaohui Hou 한국탄소학회 2023 Carbon Letters Vol.33 No.7

Exploring cheap and efficient oxygen evolution reaction (OER) catalysts is extremely vital for the commercial application of advanced energy storage and conversion systems. Herein, a self-supporting Co3S4/ S-doped reduced graphene oxide ( Co3S4/S-rGO) film catalyst is successfully prepared by a blade coating coupled with high-temperature annealing strategy, and its morphology, structure and composition are measured and analyzed. It is substantiated that the as-synthesized Co3S4/ S-rGO film possesses unique self-supporting structure, and is composed of uniformly dispersed Co3S4 nanoparticles and highly conductive S-rGO, which benefit the exposure of catalytic sites and electron transfer. By reason of the synergistic effect of the two individual components, the self-supporting Co3S4/ S-rGO film catalyst displays outstanding catalytic performance towards OER. As a consequence, the Co3S4/ S-rGO film catalyst delivers an overpotential of 341 mV at 10 mA cm-2, and the current attenuation rate is only 2.6% after continuous operation for 4 h, verifying excellent catalytic activity and durability. Clearly, our results offers a good example for the construction of high-performance self-supporting carbon-based composite film catalysts for critical electrocatalytic reactions.

Comparison of gastric-jejunum pouch anastomosis and Billroth-II reconstructions after distal gastrectomy: a propensity score matching analysis

Guangyu Chen*,Long Cheng*,Liye Liu,Guode Luo,Ming Li,Yi Wen,Tao Wang,Yongkuan Cao 대한외과학회 2022 Annals of Surgical Treatment and Research(ASRT) Vol.103 No.2

Purpose: Our study aimed to make a propensity score matching (PSM) analysis on the clinical application of gastric- jejunum pouch anastomosis (GJPA) and Billroth-II anastomosis after distal gastrectomy. Methods: We collected clinical data from 249 patients who received distal gastrectomy from January 2016 to July 2020. According to the reconstruction method used, all patients were divided into the Billroth-II group and the GJPA group. Clinical data and operation complications were analyzed. Results: The clinical characteristics of the 2 groups were comparable after PSM. In the Billroth-II group, the incidence rate of delayed gastric emptying was higher than that in the GJPA group. Fewer patients suffered reflux gastritis in the GJPA group. The RGB (residue, gastritis, and bile) scores related to the severity of bile reflux into the remnant stomach, gastritis, and residue were higher in the Billroth-II group. Postoperative nutritional status and Visick classification demonstrated that postoperative subjective feelings in the GJPA group were improved significantly. Conclusion: The application of GJPA in reconstruction after distal gastrectomy is safe, economical, and reliable. This reconstruction improved the quality of life of patients. It is worth popularizing widely in clinical settings.

The prognostic significance of estrogen and progesterone receptors in grade I and II endometrioid endometrial adenocarcinoma: hormone receptors in risk stratification

Jun Guan,Liying Xie,Xuezhen Luo,Bingyi Yang,Hongwei Zhang,Qin Zhu,Xiaojun Chen 대한부인종양학회 2019 Journal of Gynecologic Oncology Vol.30 No.1

Objectives: Although patients with grade I and II endometrioid endometrial adenocarcinoma (EEA) are considered with good prognosis, among them 15%–25% died in 5 years. It is still unknown whether integrating estrogen receptor (ER) and progesterone receptor (PR) into clinical risk stratification can help select high-risk patients with grade I–II EEA. This study was to investigate the prognostic value of ER and PR double negativity (ER/ PR loss) in grade I–II EEA, and the association between ER/PR loss and The Cancer Genome Atlas (TCGA) classification. Methods: ER and PR were assessed by immunohistochemistry on hysterectomy specimens of 903 patients with grade I–II EEA. ER and PR negativity were determined when <1% tumor nuclei were stained. Gene expression data were obtained from the TCGA research network. Results: Compared with ER or PR positive patients (n=868), patients with ER/PR loss (n=35) had deeper myometrial infiltration (p=0.012), severer FIGO stage (p=0.004), and higher rate of pelvic lymph node metastasis (p=0.020). In univariate analysis, ER/PR loss correlated with a shorter progression-free survival (PFS; hazard ratio [HR]=5.25; 95% confidence interval [CI]=2.21–12.52) and overall survival (OS; HR=7.59; 95% CI=2.55–22.60). In multivariate analysis, ER/PR loss independently predicted poor PFS (HR=3.77; 95% CI=1.60–10.14) and OS (HR=5.56; 95% CI=1.37–22.55) for all patients, and poor PFS for patients in stage IA (n=695; HR=5.54; 95% CI=1.28–23.89) and stage II–IV (n=129; HR=5.77; 95% CI=1.57–21.27). No association was found between ER/PR loss and TCGA classification. Conclusion: Integrating ER/PR evaluation into clinical risk stratification may improve prognosis for grade I–II EEA patients.

Insulin resistance and overweight prolonged fertility-sparing treatment duration in endometrial atypical hyperplasia patients

Bingyi Yang,Liying Xie,Hongwei Zhang,Qin Zhu,Yan Du,Xuezhen Luo,Xiaojun Chen 대한부인종양학회 2018 Journal of Gynecologic Oncology Vol.29 No.3

Objective: Our previous study showed that insulin resistance (IR) was related to endometrial hyperplasia as well as endometrial cancer. But the exact impact of IR on fertility-sparing treatment in endometrial hyperplasic disease is unclear. This study investigated how IR affects fertility-sparing treatment in endometrial atypical hyperplasia (EAH) patients. METHODS: The 151 EAH patients received fertility-sparing treatment were retrospectively investigated. All patients received high-dose progestin combined with hysteroscopy. Therapeutic effects were evaluated by hysteroscopy every 3 months during the treatment. RESULTS: The median age was 33.0 years old (range, 21-54 years old). Sixty-one patients (40.4%) were insulin resistant. Three patients were excluded from the analysis because they chose hysterectomy within 3 months after initiation of progestin treatment. The 141 out of 148 (95.3%) patients achieved complete response (CR). No difference was found in cumulative CR rate between those with or without IR (90.2% vs. 95.6%, p=0.320). IR significantly affected therapeutic duration to achieve CR (8.1±0.5 months with IR vs. 6.1±0.4 months without IR, p=0.004). Overweight (body mass index [BMI]≥25 kg/m²) was associated with higher risk of treatment failure (odds ratio=5.61; 95% confidence interval=1.11-28.35; p=0.040) and longer therapeutic duration to achieve CR (7.6±0.5 months vs. 6.3±0.4 months, p=0.019). EAH patients with both IR and overweight (IR+BMI+) had the longest therapeutic time compared with other patients (8.8±0.6 months vs. 5.6±0.7, 6.3±0.4, and 6.4±0.8 months for IR-BMI+, IR-BMI-, and IR+BMI-, respectively, p=0.006). CONCLUSION: IR and overweight were associated with longer therapeutic duration in EAH patients receiving progestin-based fertility-sparing treatment.

Progress in Adsorption-Enhanced Hydrogenation of CO2 on Layered Double Hydroxide (LDH) Derived Catalysts

Xin Fang,Chuang Chen,He Jia,Yingnan Li,Jian Liu,Yisong Wang,Yanli Song,Tao Du,Liying Liu 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.95 No.-

It is acknowledged as a promising strategy to reduce excessive CO2 emissions by catalytic conversion tovalue-added chemicals, in which layered double hydroxide (LDH) derived catalysts play essential roles. Inthe present review, latest progresses were summarized to gain insights on this issue. LDH-derivedcatalysts can be prepared via various methods and possess favorable characteristics of reversibletopotactic transformation for further development. Compared to conventional catalysts, they showspecific advantages in specific surface area, metal element dispersion and active site distribution. Despiteof distinguished LDH-derived catalysts applied in CO2 reduction reactions to methane, methanol,hydrocarbons, etc., state-of-art LDH-derived catalysts consisted of catalyst-adsorbent synergistic systemare recently constructed to employ the surface CO2 adsorption boundary layer to increase the CO2 partialpressure near active sites for hydrogenation. The overall catalytic performance is thus promoteddramatically. Accordingly, the strategy of adsorption-enhanced hydrogenation is expected to facilitatethe industrialization of CO2 hydrogenation and is instructive for catalyst design in future.

Genome-Wide Association Analysis to Search for New Loci Associated with Lifelong Premature Ejaculation Risk in Chinese Male Han Population

Wang Fei,Luo Defan,Chen Jianxiang,Pan Cuiqing,Wang Zhongyao,Fu Housheng,Xu Jianbing,Yang Meng,Mo Shaowei,Zhuang Liying,Ye Liefu,Wang Weifu 대한남성과학회 2022 The World Journal of Men's Health Vol.40 No.2

Purpose: Genetic factors play an indispensable role in the pathogenesis of lifelong premature ejaculation (LPE). The suscep-tibility genes/SNPs that have been discovered are very limited and can only explain part of the genetic effects of LPE. There-fore, discovering more genetic polymorphisms associated with the occurrence and development of LPE will help reveal the pathogenesis of LPE. Materials Materials and and Methods:Methods: We conducted a genome-wide association study of LPE in 486 Chinese male Han people (cases and controls). We used Gene Titan multi-channel instrument and Axiom Analysis Suite 6.0 software for genotyping. Imputation was performed by IMPUTE2 software and the 1000 Genomes Project (Phase3) was used as reference for haplotype. Finally, logistic regression analysis was performed on all loci that passed the quality control. The odds ratio and 95% confidence in-terval were calculated to determine the association between each SNPs and Chinese male Han population LPE risk. Results:Results: The results showed that a total of 33 genetic variants in 13 genes (LACTBL1 , SSBP3 , ACOT11 , LINC02486 , TMEM154, LINC01098, NONE, HCG27, HLA-C, TNFSF8, TNC, FAM53B, SULF2) have a suggestively significant genome-wide association with LPE risk (p<5×10-6). Conclusions:Conclusions: This study is the first to conduct a GWAS on LPE in Chinese male Han population 33 genetic polymorphisms have a suggestive genome-wide association with LPE risk. This study have provided data supplement for the genetic loci of LPE risk, and laid a scientific foundation for the pathogenesis and the targeted therapy of LPE.