A novel semi-IPN hydrogel: Preparation, swelling properties and adsorption studies of Co (II)

Xiaohong Wang,Haiqian Hou,Yujun Li,Yingying Wang,Chen Hao,Cunwang Ge b 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.41 No.-

A range of super-absorbent semi-IPN hydrogels—polyvinyl alcohol/poly (acrylic acid-co-acrylic amide)(PVA-P(AA-co-AM)) were synthesized via free radical polymerization method under ultrasound-assistedcondition. L16 (45) orthogonal experiments were designed to optimize the synthesis conditions and thesuccess was characterized by FTIR, SEM and TGA. Swelling capacities were studied in various pH solutionand saline solution whose results indicated that pH in solution shows an obvious influence on it and thesalt resistance is greater in salt solution of low valence relative to that of high valence. Meanwhile, itsswelling behavior was evaluated in water solution, which revealed that the swelling process conformedto the Schott model and the diffusion type was non-Fickian diffusion. Moreover, the adsorption on cobalt(II) from aqueous solutions was also investigated in the paper. The optimumpH value was found close to4 for the cobalt (II) adsorption and it was discovered that adsorption kinetics and adsorption isothermsfor cobalt (II) were in accordance with the pseudo-second-order model and the Freundlich modelrespectively. Besides, thermodynamic parameters were calculated for the cobalt (II) adsorption and thefindings revealed that the adsorption behavior is spontaneous and endothermic.

3.2-kW 9.7-GHz Polarization-maintaining Narrow-linewidth All-fiber Amplifier

Hang Liu,Yujun Feng,Xiaobo Yang,Yao Wang,Hongming Yu,Jue Wang,Wanjing Peng,Yanshan Wang,Yinhong Sun,Yi Ma,Qingsong Gao,Chun Tang 한국광학회 2024 Current Optics and Photonics Vol.8 No.1

We present a Yb-doped narrow-linewidth polarization-maintaining (PM) all-fiber amplifier that achieves a high mode-instability (MI) threshold, high output power, and 9.7-GHz spectral linewidth. Six wavelength-multiplexed laser diodes are used to pump this amplifier. First, we construct a high-power fiber amplifier based on a master oscillator-power amplifier (MOPA) configuration for experiments. Subsequently, we examine the MI threshold by individually pumping the amplifier with wavelengths of 976, 974, 981, 974, and 981 nm respectively. The experimental results demonstrate that the amplifier exhibits a high MI threshold (>3.5 kW) when pumped with a combination of wavelengths at 974 and 981 nm. Afterward, we inject an optimized phase-modulated seed with a nearly flat-top spectrum into this amplifier. Ultimately, laser output of 3.2 kW and 9.7 GHz are obtained.

SLC39A10 promotes malignant phenotypes of gastric cancer cells by activating the CK2-mediated MAPK/ERK and PI3K/AKT pathways

Ren Xiaojuan,Feng Chao,Wang Yubo,Chen Pu,Wang Simeng,Wang Jianling,Cao Hongxin,Li Yujun,Ji Meiju,Hou Peng 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Solute carrier family 39 member 10 (SLC39A10) belongs to a subfamily of zinc transporters and plays a key role in B-cell development. Previous studies have reported that its upregulation promotes breast cancer metastasis by enhancing the influx of zinc ions (Zn2+); however, its role in gastric cancer remains totally unclear. Here, we found that SLC39A10 expression was frequently increased in gastric adenocarcinomas and that SLC39A10 upregulation was strongly associated with poor patient outcomes; in addition, we identified SLC39A10 as a direct target of c-Myc. Functional studies showed that ectopic expression of SLC39A10 in gastric cancer cells dramatically enhanced the proliferation, colony formation, invasiveness abilities of these gastric cancer cells and tumorigenic potential in nude mice. Conversely, SLC39A10 knockdown inhibited gastric cancer cell proliferation and colony formation. Mechanistically, SLC39A10 exerted its carcinogenic effects by increasing Zn2+ availability and subsequently enhancing the enzyme activity of CK2 (casein kinase 2). As a result, the MAPK/ERK and PI3K/AKT pathways, two major downstream effectors of CK2, were activated, while c-Myc, a downstream target of these two pathways, formed a vicious feedback loop with SLC39A10 to drive the malignant progression of gastric cancer. Taken together, our data demonstrate that SLC39A10 is a functional oncogene in gastric cancer and suggest that targeting CK2 is an alternative therapeutic strategy for gastric cancer patients with high SLC39A10 expression.

Research of fast point cloud registration method in construction error analysis of hull blocks

Wang, Ji,Huo, Shilin,Liu, Yujun,Li, Rui,Liu, Zhongchi The Society of Naval Architects of Korea 2020 International Journal of Naval Architecture and Oc Vol.12 No.1

The construction quality control of hull blocks is of great significance for shipbuilding. The total station device is predominantly employed in traditional applications, but suffers from long measurement time, high labor intensity and scarcity of data points. In this paper, the Terrestrial Laser Scanning (TLS) device is utilized to obtain an efficient and accurate comprehensive construction information of hull blocks. To address the registration problem which is the most important issue in comparing the measurement point cloud and the design model, an automatic registration approach is presented. Furthermore, to compare the data acquired by TLS device and sparse point sets obtained by total station device, a method for key point extraction is introduced. Experimental results indicate that the proposed approach is fast and accurate, and that applying TLS to control the construction quality of hull blocks is reliable and feasible.

Research of fast point cloud registration method in construction error analysis of hull blocks

Wang, Ji,Huo, Shilin,Liu, Yujun,Li, Rui,Liu, Zhongchi The Society of Naval Architects of Korea 2020 International Journal of Naval Architecture and Oc Vol.12 No.-

The construction quality control of hull blocks is of great significance for shipbuilding. The total station device is predominantly employed in traditional applications, but suffers from long measurement time, high labor intensity and scarcity of data points. In this paper, the Terrestrial Laser Scanning (TLS) device is utilized to obtain an efficient and accurate comprehensive construction information of hull blocks. To address the registration problem which is the most important issue in comparing the measurement point cloud and the design model, an automatic registration approach is presented. Furthermore, to compare the data acquired by TLS device and sparse point sets obtained by total station device, a method for key point extraction is introduced. Experimental results indicate that the proposed approach is fast and accurate, and that applying TLS to control the construction quality of hull blocks is reliable and feasible.

중국인 유학생의 코로나 스트레스가 정신건강과 상호활성화에 미치는 영향 : 문화적응 스트레스의 매개효과를 중심으로

왕유준,오인수,류신혜 이화여자대학교 교육과학연구소 2021 교육과학연구 Vol.52 No.3

The purpose of this study was to identify how the increased stress caused by COVID-19 affects the mental health and covitality of Chinese students and ensure whether these effects are mediated by acculturative stress. In particular, we assumed that the relationship of these study variables will vary depending on the acculturation types of Chinese students, and also confirmed that there were differences in the effects of COVID-19 stress on mental health depending on the acculturation type. To this end, the cluster analysis and route analysis were conducted on the results of a survey of 365 Chinese students living in Korea. According to the cluster analysis, Chinese students were divided into three acculturation types of integration, separation, and marginalization, while students belonging to the integration type had a low level of mental health problems and a high level of covitality. Path analysis has shown that acculturative stress partially mediates COVID-19 stress and mental health. On the other hand, acculturative stress has been shown to fully mediate the relationship between COVID-19 stress and covitality. This showed that the COVID-19 stress noted in this study had a significant impact on the mental health and covitality of Chinese students and confirmed the importance of acculturative stress in this relationship. The results of this study are significant in that they provided educational and counseling intervention to improve the mental health and covitality of Chinese students in this COVID-19 situation in terms of cultural adaptation. 본 연구의 목적은 코로나19로 인해 증가된 스트레스가 중국인 유학생의 정신건강문제와 상호활성화에 어떠한 영향을 미치는지와 이러한 영향을 문화적응 스트레스가 매개하는지를 확인하는 것이다. 특히 중국인 유학생의 문화적응 유형에 따라 연구 변인의 관계가 다를 것으로 가정하고, 유형에 따라 코로나 스트레스가 정신건강에 미치는 영향의 차이도 확인하였다. 이를 위하여 한국에 거주하고 있는 중국인 유학생을 365명을 대상으로 실시한 설문조사 결과에 대해 군집분석과 경로분석을 실시하였다. 군집분석 결과 중국인 유학생은 통합, 분리, 주변화의 3가지의 문화적응유형으로 구분되었고 통합유형에 속한 학생이 정신건강문제의 수준은 낮고 상호활성화 수준은 높았다. 경로분석 결과 문화적응 스트레스는 코로나19 스트레스와 정신건강을 부분 매개하는 것으로 확인되었으며, 문화적응 스트레스는 코로나19 스트레스와 상호활성화의 관계를 완전 매개하는 것으로 나타났다. 이를 통해 본 연구에서 주목한 코로나 스트레스가 중국인 유학생의 정신건강 및 상호활성화에 유의미한 영향을 미치며 그 관계에서 문화적응 스트레스의 중요성을 확인할 수 있었다. 이러한 연구의 결과는 코로나 상황에서 중국인 유학생의 정신건강과 상호활성화를 향상시키기 위한 교육 및 상담적 개입 방안을 문화적응의 관점에서 제공했다는 점에서 의의를 지닌다.

Catalytic chlorination of methylphenyldichlorosilane with gaseous chlorine to chlorinated methylphenyldichlorosilanes over Lewis acids

Yujun Fu,Hengbo Yin,Yiqian Jiang,Lingqin Shen,Yonghai Feng,Aili Wang 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.3

Methylchlorophenyldichlorosilane (MeClPhSiCl2) and methyldichlorophenyldichlorosilane (MeCl2Ph-SiCl2) were synthesized by the catalytic chlorination of methylphenyldichlorosilane (MePhSiCl2) withCl2 over Lewis acid catalysts. The catalytic activities of Lewis acid catalysts were in an order ofFeCl3 > SbCl5 > AlCl3 > SnCl4. However, FeCl3 also highly catalyzed the cleavage of chlorophenyl–siliconbond to form chlorobenzene. At a low mole ratio of SbCl5 to MePhSiCl2 of 1.4 × 10-5:0.45, the yield ofMeClPhSiCl2 was around 60% after reacting at 25–100 8C for 15–20 h. At a high mole ratio of1.4 × 10-4:0.45, the yield of MeCl2PhSiCl2 reached 44% after reacting at 80–100℃ for 20 h.

Long noncoding RNA NEAT1 suppresses hepatocyte proliferation in fulminant hepatic failure through increased recruitment of EZH2 to the LATS2 promoter region and promotion of H3K27me3 methylation

Qiang Wang,Lian Liu,Sheng Zhang,Yingzi Ming,Shu Liu,Ke Cheng,Yujun Zhao 생화학분자생물학회 2020 Experimental and molecular medicine Vol.52 No.-

Fulminant hepatic failure (FHF) refers to the rapid development of severe acute liver injury with impaired synthetic function and encephalopathy in people with normal liver or well-compensated liver disease. This study aimed to investigate the function of long noncoding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) on the proliferation and apoptosis of hepatocytes in FHF. Our results revealed that lncRNA NEAT1 was upregulated in cell and animal models of FHF induced by D-galactosamine (D-GalN)/lipopolysaccharide (LPS). Overexpression of lncRNA NEAT1 resulted in elevated hepatocyte apoptosis and impaired large tumor-suppressor kinase 2 (LATS2) expression and proliferation. Functional analysis revealed that knockdown of lncRNA NEAT1 inhibited hepatocyte apoptosis and induced proliferation both in vitro and in vivo. RNA immunoprecipitation and chromatin immunoprecipitation assays demonstrated that lncRNA NEAT1 recruited enhancer of zeste homolog 2 (EZH2) to the LATS2 promoter and repressed LATS2 expression. Furthermore, ectopic expression of LATS2 increased proliferation and inhibited hepatocyte apoptosis by regulating the Hippo/Yes-associated protein (YAP) signaling pathway. Taken together, our findings indicate that lncRNA NEAT1 might serve as a novel target for FHF therapy due to its regulation of H3K27me3 methylation-dependent promotion of LATS2.

Simulation of the Structural Parameters of Anti-resonant Hollow-core Photonic Crystal Fibers

Qing Liu,Yujun Feng,Yinhong Sun,Zhe Chang,Yanshan Wang,Wanjing Peng,Yi Ma,Chun Tang 한국광학회 2022 Current Optics and Photonics Vol.6 No.2

Anti-resonant hollow-core photonic crystal fiber (AR-HCF) has unique advantages, such as low nonlinearity and high damage threshold, which make it a promising candidate for high-power laser delivery at distances of tens of meters. However, due to the special structure, optical properties such as modefield profile and bending loss of hollow-core fibers are different from those of solid-core fibers. These differences have limited the widespread use of AR-HCF in practice. In this paper we conduct numerical analysis of AR-HCFs with different structural parameters, to analyze their influences on an AR-HCF’soptical properties. The simulation results show that with a 23-μm air-core diameter, the fundamentalmode profile of an AR-HCF can well match that of the widely used Nufern’s 20/400 fiber, for nearlysingle-mode power delivery applications. Moreover, with the ratio of cladding capillary diameter to aircore diameter ranging from 0.6 to 0.7, the AR-HCF shows excellent optical characteristics, including low bending sensitivity while maintaining single-mode transmission at the same time. We believe these results lay the foundation for the application of AR-HCFs in the power delivery of high power fiber laser systems.

Extracting phenolic compounds from aqueous solutions by cyclohexanone, a highly efficient extractant

Weibin Cai,Haihan Wang,Q. Gary Yang,Tiankun Liu,Yujun Wang 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.116 No.-

Methyl isobutyl ketone (MIBK) and diisopropyl ether (DIPE) are two commonly used extractants in industry,but their efficiency in extracting phenols, especially polyhydroxyphenols, is low. In the work, ahighly-efficient extractant was proposed to extract phenolic compounds, including polyhydroxyphenols. The interactions between three extractants, cyclohexanone (CYC), MIBK and DIPE, and phenols were analyzedby the COSMO-RS method and CYC shows stronger interactions with phenols than MIBK and DIPE. The results of Fourier-transform infrared spectroscopy (FTIR) show that strong hydrogen bonds areformed between CYC and phenolic compounds, in agreement with the results of the COSMO-RS method. The effects of concentration, temperature and pH values on the extractant performance were studied. Results showed that the performance of CYC is the best, followed by MIBK and DIPE, whose performanceis the worst. As CYC was used as the extractant, the distribution coefficients of the three phenolic compounds,phenol, resorcinol and phloroglucinol, are 96.7, 47.8, 13.0, respectively. These values are 35%,263%, and 160% larger than those of phenol, resorcinol and phloroglucinol, respectively, correspondingto MIBK. CYC is a highly-efficient extractant for the extraction of phenolic compounds, includingpolyhydroxyphenol.