http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Liming Dai,Qian Zhao,Haibo Zhao,Yingying Li,Tingshun Jiang 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.5
Three different mesoporous molecular sieves, including MCM-41, MCM-48, and SBA-15, were synthesized by hydrothermal process and characterized by XRD, BET and TEM. The chlorine-aluminate acidic ionic liquid of 1-butyl-3-methylimidazolium chloride-aluminum chloride ([Bmim]Cl-AlCl3, denoted as Al-ILs) was prepared by twostep method. The immobilized ionic liquid (SBA-15/Al-ILs, MCM-41/Al-ILs, MCM-48/Al-ILs) was prepared through impregnating Al-ILs. The structures of composite catalysts were characterized by XRD, BET, FT-IR, TEM and XPS. The amounts of aluminum present in the resulting composite catalysts were detected by ICP-AES to calculate the amount of AL-ILs impregnated. The ketalization between cyclohexanone and ethanediol was used as the model reaction to test the catalytic activities of the composite catalysts. The effects of molar ratio of the reactants, reaction time, the catalyst dose, as well as the addition of cyclohexane were discussed in detail. Also, catalytic activities of three catalysts with different pore sizes were compared. Under comparable conditions, the SBA-15/Al-ILs composite catalyst exhibited much high catalytic activity and gave a maximum yield that was ca. 85.1%.
Zhao Shuang,Song Gang,Chen Jian,Yao Man,Liu Liming 한국물리학회 2022 Current Applied Physics Vol.33 No.-
The interface between Mg alloy and the intermetallic compounds (IMCs) is the weak point during the welding of Mg alloy and steel. The models of AlNi surface under different number of absorbed magnesium atoms were established. The absorption energy and electronic properties of the Nth (N represents the number of Mg atoms, which may be 1, 2, 3, and 4 in this paper) Mg atom on the AlNi surface were calculated using first-principles calculations. The results show that the previously absorbed Mg atoms will promote the absorption of the latter Mg atom when the distance between them is equal or less than 2.89 Å. The absorption energy of the Mg atoms on the AlNi surface is related to the electronic exchange between different atoms. The results will provide a new perspective for understanding the atomic scale mechanism of the bonding between the Mg atom and AlNi IMCs.
Zhao Jingyi,Li Bingyan,Ren Yongxia,Liang Tiansong,Wang Juan,Zhai Suna,Zhang Xiqian,Zhou Pengcheng,Zhang Xiangxian,Pan Yuanyuan,Gao Fangfang,Zhang Sulan,Li Liming,Yang Yongqiang,Deng Xiaoyu,Li Xiaole,C 생화학분자생물학회 2021 Experimental and molecular medicine Vol.53 No.-
Compelling evidence has indicated the vital role of lysine-specific demethylase 4 A (KDM4A), hypoxia-inducible factor-1α (HIF1α) and the mechanistic target of rapamycin (mTOR) signaling pathway in nasopharyngeal carcinoma (NPC). Therefore, we aimed to investigate whether KDM4A affects NPC progression by regulating the HIF1α/DDIT4/mTOR signaling pathway. First, NPC and adjacent tissue samples were collected, and KDM4A protein expression was examined by immunohistochemistry. Then, the interactions among KDM4A, HIF1α and DDIT4 were assessed. Gain- and loss-of-function approaches were used to alter KDM4A, HIF1α and DDIT4 expression in NPC cells. The mechanism of KDM4A in NPC was evaluated both in vivo and in vitro via RT-qPCR, Western blot analysis, MTT assay, Transwell assay, flow cytometry and tumor formation experiments. KDM4A, HIF1α, and DDIT4 were highly expressed in NPC tissues and cells. Mechanistically, KDM4A inhibited the enrichment of histone H3 lysine 9 trimethylation (H3K9me3) in the HIF1α promoter region and thus inhibited the methylation of HIF1α to promote HIF1α expression, thus upregulating DDIT4 and activating the mTOR signaling pathway. Overexpression of KDM4A, HIF1α, or DDIT4 or activation of the mTOR signaling pathway promoted SUNE1 cell proliferation, migration, and invasion but inhibited apoptosis. KDM4A silencing blocked the mTOR signaling pathway by inhibiting the HIF1α/DDIT4 axis to inhibit the growth of SUNE1 cells in vivo. Collectively, KDM4A silencing could inhibit NPC progression by blocking the activation of the HIF1α/DDIT4/mTOR signaling pathway by increasing H3K9me3, highlighting a promising therapeutic target for NPC.
Liming Chen,Lulu Zhao,Jie Xu,Jinlin Long,Linxi Hou 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.8
Metal-free photocatalysts trithiocyanuric acid (C3N3S3) and its polymers were one-step synthesized and used for selective aerobic oxidation of benzyl alcohol under visible light. The S–S bridged C3N3S3 polymers showed higher oxidation activity with increasing polymerization time and reached a maximum at 40 h. As a major factor, catalysts' solubility in water at different temperatures (from 298.15K to 368.15 K) was measured at atmospheric pressure. The obtained data were correlated by polynomial empirical equation and modified Apelblat equation, respectively. Experimental results proved that the solubility of C3N3S3 and its polymers increased with increasing temperature. The solubility of C3N3S3 polymers with lower polymerization degree (DP) were better than that of parent C3N3S3 owing to the hydrophilicity caused by a low symmetry and disorder structure, whereas the higher DP could lead to the decrease of polymer solubility and further affect the photocatalytic activity. Thermodynamic properties of the solution system including the enthalpy (△H0S) and heat capacity (c0p) were calculated by the modified Apelblat equation.
Preparation and Oxidation resistance of Nanometre-sized Copper Powders
Liu, Zhijie,Zhao, Bin,Zhang, Zongtao,Hu, Liming 한국재료학회 1995 Fabrication and Characterization of Advanced Mater Vol.2 No.4
Using chemical reduction emthod in aqueous solutions, ultrafine copper powders with mean diameter about 50nm were prepared and the stability of nanometre-sized copper powders stored in deionic water was studied. The oxidation resistance of nanometre-sized copper powders was greatly improved by using silver-coating method and surface phosphazition. The oxidizing temperatures were beyond 25$0^{\circ}C$.
Zhu Kang,Zhao Xinwen,Zhang Liming,Yu Hang 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.11
The control rod drive system is critical to the reactor's reliable operation. The performance of its control system and mechanical system will gradually deteriorate because of operational and environmental stresses, thus increasing the reactor's operational risk. Currently there are few researches on the agingrelated degradation of the entire control rod drive system. Because it is difficult to quantify the effect of various environmental stresses and establish an accurate physical model when multiple mechanisms superimposed in the degradation process. Therefore, this paper investigates the aging-related degradation of a control rod drive system by integrating Dynamic Object-Oriented Bayesian Network and Hidden Markov Model. Uncertainties in the degradation of the control system and mechanical system are addressed by using fuzzy theory and the Hidden Markov Model respectively. A system which consists of eight control rod drive mechanisms divided into two groups is used to demonstrate the method. The aging-related degradation of the control rod drive system is analyzed by the Bayesian inference algorithm based on the accelerated life test data, and the impact of different operating schemes on the system performance is also investigated. Meanwhile, the components or units that have major impact on the system's performance are identified at different operational phases. Finally, several essential safety measures are suggested to mitigate the risk caused by the system degradation
( Xiaojun Zhang ),( Liming Mu ),( Jie Zhao ),( Chunxiang Xu ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.6
Vehicular ad-hoc networks (VANETs) have become increasingly significant in intelligent transportation systems, they play a great role in improving traffic safety and efficiency. In the deployment of intelligent VANETs, intelligent vehicles can efficiently exchange important or urgent traffic information and make driving decisions. Meanwhile, secure data communication and vehicle’s identity privacy have been highlighted. To cope with these security issues, in this paper, we construct an efficient anonymous authentication scheme with secure communication in intelligent VANETs. Combing the ElGamal encryption technique with a modified Schnorr signature technique, the proposed scheme provides secure anonymous authentication process for encrypted message in the vehicle-to-infrastructure communication model, and achieves identity privacy, forward security, and reply attack resistance simultaneously. Moreover, except the trusted authority (TA), any outside entity cannot trace the real identity of an intelligent vehicle. The proposed scheme is designed on an identity-based system, which can remove the costs of establishing public key infrastructure (PKI) and certificates management. Compared with existing authentication schemes, the proposed scheme is much more practical in intelligent VANETs.