Synthesis of single azo disperse dye containing double ester and determination of crystal structure

Hong Xu,Zhengyu Zhang,Chunling Zheng 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.12

The synthesis, crystal structure analysis and characterization of a monoazo dye, 4-((2,6-dichloro-4-nitro phenyl)azo)-N-(diacetyl oxygen ethyl)aniline, are reported. The dye crystallised in the triclinic system, space group P-1 with a=8.1663(3) Å, b= 9.4222(3) Å, c=15.4694(5) Å, α=78.9130(10)o, β=75.019(2)o, γ =70.787(2)o, V=1078.26(6)Å3 and Z=2. There is only one molecule in the asymmetric unit. The dihedral angle between the two phenyl rings is 53.4 Å. In the crystal structure, intermolecular C-H…O hydrogen bonds link the molecules into centrosymmetric dimers,forming R22(30) ring motifs, in which they may be effective in the stabilization of the structure. Between the phenyl rings, the π…π stacking (interactions) may further stabilize the structure.

Functional mechanisms for diabetic nephropathy-associated genetic variants

Hong Xu,Chengxin Gong,Yonghu Xu,Yongfang Fan,Xingzi Liu,Chaopeng Xiong,Luling He,Changle Liu,Shenqiang Rao,Wen Xiao,Lu Ding,Lan Tang,Fangfang Hu,Mengqi Xiong,Mei Yang,Shangdong Liang 한국유전학회 2016 Genes & Genomics Vol.38 No.7

Diabetic nephropathy (DN) is one of the major complications of diabetes. A tremendous amount of genetic variations have been identified to be associated with DN. However, most of them only generate from statistical associations at the DNA level, generally without direct functional evidence regarding their association mechanisms underlying DN. Based on the publicly available datasets and resources, this study performed integrative analyses (expression quantitative trait loci analysis, differential gene expression analysis and functional prediction analysis) to detect the molecular functional mechanisms underlying the associations for DN. Among 150 selected (P\E-4) genetic associations that were archived in the public databases, two single nucleotide polymorphisms (SNPs) (rs3135377 and rs9469220) have been found to act as cis-effect regulators of the ‘‘identified’’ gene (HLADRA and HLA-DRB1). These eQTL genes have differential expression signals in the DN-associated cell groups. These SNPs were predicted as regulatory sites by utilizing online prediction tools. Our data suggest potential mechanistic links underlying the association between DN and two identified SNPs. These results could help us to have a deeper understanding of the functional relevance of genetic variants with susceptibility to DN, which is useful for pursuit of in-depth validation studies to dissect their involvements and molecular functional mechanisms in DN.

Application of artificial neural network for the critical flow prediction of discharge nozzle

Hong Xu,Tao Tang,Baorui Zhang,Yuechan Liu 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.3

System thermal-hydraulic (STH) code is adopted for nuclear safety analysis. The critical flow model(CFM) is significant for the accuracy of STH simulation. To overcome the defects of current CFMs (lowprecision or long calculation time), a CFM based on a genetic neural network (GNN) has been developedin this work. To build a powerful model, besides the critical mass flux, the critical pressure and criticalquality were also considered in this model, which was seldom considered before. Comparing with thetraditional homogeneous equilibrium model (HEM) and the Moody model, the GNN model can predictthe critical mass flux with a higher accuracy (approximately 80% of results are within the ±20% errorlimit); comparing with the Leung model and the Shannak model for critical pressure prediction, the GNNmodel achieved the best results (more than 80% prediction results within the ±20% error limit). For thecritical quality, similar precision is achieved. The GNN-based CFM in this work is meaningful for the STHcode CFM development

Pattern Automatic Generation for Men's Trousers

Hong Xu 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.5

理学背景下武夷精舍与玉山书院周边的“人居环境” 比较研究 - 以中国武夷九曲和韩国玉山九曲为中心

彭鴻緖 ( Peng¸ Hong-xu ) 한국서원학회 2020 한국서원학보 Vol.11 No.-

본 논문은 중국 武夷山 武夷精舍와 玉山書院 주변의 ‘人居環境’을 武夷九曲과 玉山書院九曲을 중심으로 비교한 논문이다. 본 논문은 총 5장으로 이뤄져있으며 중국 九曲園林과 한국구곡원림의 연원관계, 한중 구곡원림의 공간분포, 한중 구곡원림의 비교로 기술되어있고, 마지막에는 결론 부분과 옥산구곡서원의 발전방향에 대한 조언이 담겨있다. 1장 <한국 서원 밖의 인거환경>에서는 중국에서 九曲이 설정되는 배경을 설명하고, 조선시기 서원들이 서원 밖의 ‘인거환경’이 주자의 무이구곡을 모방하게 된 역사적 배경을 설명했다. 2장 <한국의 구곡원림과 중국의 배경연원>에서는 조선시기 유학자들의 朱子 숭배와 당쟁에 대한 회의로 산수자연을 이상향으로 간주하면서 구곡원림이 설정되었다는 점과 구곡의 造型상의 특징을 기술했다. 또한 무이산 하천과 한국의 하천에서 나타나는 특징을 언급하고 구곡이 들어선 입지를 설명했다. 3장 <한국 구곡원림의 공간분포>에는 전국에 분포된 구곡을 지역별로 통계를 내고, 구곡이 집중된 지역의 지리적 특성과 역사적 연원을 설명했다. 아울러 일제강점기에서 현재까지 설정된 구곡도 설명했다. 4장 <한중 구곡원림 비교>는 무이구곡과 옥산구곡의 특징을 각각 기술하고, 이를 토대로 두 곳을 비교했다. 이곳에서는 지형과 지질, 구곡의 설정자와 후대 학자, 문화와 사상, 시화와 석각, 경관 구성, 경의의 부여 등 여러 방면으로 나눠 상세하게 설명했다. 5장 <연구 정리와 발전 건의>는 이상의 연구를 정리하고 옥산서원과 옥산구곡이 갖는 현대적인 의미를 설명하고, 옥산서원과 옥산구곡을 더욱 발전시킬 수 있는 방안에 대해서 몇 가지 조언을 했다. This study is about compare the ‘residential environments’ between Mooijungsa in Mount Mooi, China and Oksan Seowon, focusing on Mooi Gugok and Oksan Seowon Gugok. This study consists of the total five chapters about the relations of origins of Gugok gardens in China and Korea, spatial distributions in both Korean and Chinese Gugok gardens, and comparison between Korean and Chinese Gugok gardens, and finally there are conclusions and suggestions for the development of Oksan Gugok Seowon. Chapter 1 < Residential environment outside the Korean Seowons > explains the background to set Gugok in China and the historical background that residential environment outside Seowons in Joseon mimicked Zhu Xi’s Mooigugok. Chapter 2 < The Korean Gugok Garden and the Origin from China > describes that Confucians in Joseon worshiped Zhu Xi and they also considered natural landscapes of mountains and waters as utopia due to their regret for factions and then, Gugok gardens was set and the garden’s characteristics in designs. In addition, the characteristics of rivers in Mount Mooi and in Korea are mentioned with the explanations on the locations of Gugok. Chapter 3 < Spatial Distribution of Korean Gugok Gardens > contains the statistics of Gugok gardens in Korea by region and explains geographical characteristics and historical origin of the regions concentrated with Gugoks. In addition, the Gugoks set between the Japanese Colonial Times and the present are also described. Chapter 4 < Comparison between Korean and Chinese Gugok Gardens > describes the respective characteristics of Mooi Gugok and Oksan Gugok and then compares both the places based on them. The chapter offers detailed descriptions with several sections including topography and geology, who set Gugok and next generations of the scholars, culture and ideas, poetic drawing and stone carving, landscaping, and making the meanings in the landscapes. Chapter 5 < Summary and Suggestions for Development > summarizes the study, explains the contemporary meanings of Oksan Seowon and Oksan Gugok, and makes some suggestions for developing them.

Rollover Prediction and Control Strategy Based on Experiment for Tractor Semitrailer Fitted with Hydraulically Interconnected Suspension

Hongxue Li,Liangsheng Liu,Longxin Zhen,Xianyi Xie,Yi Xu 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.1

Hydraulically interconnected suspension (HIS) system has theoretically and experimentally been proved to suppress rollover of non-articulated vehicle, but lacking of vibration studies on more complex nonlinear systems such as multi-axle combination vehicle. Hence, this paper presents rollover threshold prediction and active disturbance rejection controller (ADRC) of a tractor semitrailer fitted with HIS based on experimental test to reduce instability of mechanical system. Firstly, a roll resistant verification of a tractor semitrailer fitted with HIS is conducted under a steady circle experiment. Furthermore, the prediction for rollover threshold to extreme maneuver is presented by incorporating robust Kalman filter (RKF) and Back Propagation neural network with genetic algorithm (GA-BP) that are both designed. Finally, an ADRC control is proposed based on control model reduced by applying least square identification and model reduction method. The results are obtained including three aspects: experimental results verify the superior anti-roll performance of vehicle fitted with HIS in comparison with traditional vehicle and are also used to assist the subsequent prediction at high speed. Prediction results highlight that the RKF algorithm performs better filtering accuracy over KF, UKF and PF methods and developed GA-BP supply the higher precision compared with the conventional BP method for the prediction, by which the lateral acceleration threshold is achieved. The results of control show ADRC control strategy obviously has faster response and smaller overshoot than fuzzy PID and regular PID controller for the stability of system.

Experimental Investigation of Output Current Variation in Biased Silicon-based Quadrant Photodetector

Hongxu Liu,Di Wang,Chenang Li,Guangyong Jin 한국광학회 2020 Current Optics and Photonics Vol.4 No.4

We report on the relationship between output current for quadrant photodetector (QPD) and bias voltage in silicon-based p-i-n (positive-intrinsic-negative) QPD examined using millisecond pulse laser (ms pulse laser) irradiation. The mechanism governing the relationship was further studied experimentally. The output current curves were obtained by carrying out QPD under different bias voltages (0~40 V) irradiated by ms pulse laser. Compared to other photodetectors, the relaxation was created in the output current for QPD which is never present in other photodetectors, such as PIN and avalanche photodetector (APD), and the maximum value of relaxation was from 6.8 to 38.0 µA, the amplitude of relaxation increases with bias value. The mechanism behind this relaxation phenomenon can be ascribed to the bias voltage induced Joule heating effect. With bias voltage increasing, the temperature in a QPD device will increase accordingly, which makes carriers in a QPD move more dramatically, and thus leads to the formation of such relaxation.

Adsorption behavior of Congo red from aqueous solution on La2O3-doped TiO2 nanotubes

Hongxu Guo,Jianhua Chen,Wen Weng,Zishan Zheng,Dongfang Wang 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.5

Composite adsorbent, TiO2 nanotubes doped by La2O3, were prepared and characterized by IR, XRD, SEM, and XPS, their adsorption properties were investigated in the aqueous solution employing Congo red as the target pollutant. The adsorption experiments exhibited that adsorption equilibrium of Congo red over the adsorbent was rapidly achieved within 10 min, and the adsorption kinetics was in accord with the pseudo-second-order kinetics model. Moreover, intraparticle diffusion was not the determining step in the entire adsorption process, and the adsorption belonged to a chemical adsorption. Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isothermal equations were utilized to fit the equilibrium adsorption data, in which the Temkin equation was verified to fit the adsorption behaviors most satisfactorily with the correlation coefficient of 0.998. The adsorption mechanism was also studied.

Facile template-free one-pot fabrication of TiO2@C microspheres with high visible-light photocatalytic degradation activity

Hongxu Guo,Zishan Zheng,Jianhua Chen,Wen Weng,Mingqiang Huang 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.36 No.-

TiO2@C microspheres were fabricated through facile template-free one-pot hydrothermal reaction, inwhich ferrocene was first simultaneously used as carbon source and structure directing agent. Thecomposite obtained have been characterized by X-ray powder diffraction, field emission scanningelectron microscopy, diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, and nitrogenadsorption–desorption isotherms. The results show that the peripheries of the microspheres are stackedby several TiO2 particles. The band gap energy the as-prepared sample is estimated to be 2.26 eV. Allcarbon species in the composite are modified on the surface of the photocatalyst. The as-preparedTiO2@C microspheres exhibited higher visible-light photocatalytic activity for the degradation of organicpollutants (Congo red and 4-nitrophenol) than that of N-doped TiO2 catalyst. The OH radicals formed inthe process of photocatalytic degradation were also detected through fluorescence technique.

Capacitor voltage balancing method for hybrid modular multilevel converters based on second‑harmonic voltage injection

Hongxu Li,Qin Wang,Qunfang Wu,Lan Xiao,Jinbo Li 전력전자학회 2024 JOURNAL OF POWER ELECTRONICS Vol.24 No.4

Due to different output voltages, capacitor voltage imbalance occurs between half-bridge sub-modules (HBSM) and fullbridge sub-modules (FBSM) in hybrid modular multilevel converters (MMCs) under a boosted modulation index (m). To address this issue, a capacitor voltage balancing method based on second-harmonic voltage injection is proposed in this paper. The mechanism of the proposed method is to eliminate the DC component in the charging power of sub-modules under the restriction that the HBSM cannot output negative voltage. The proposed method is divided into two cases according to m. Case 1 is used when m ≤ 1.4, while Case 2 is implemented when m > 1.4. When compared with similar capacitor voltage balancing methods, the proposed SVI method has a simpler structure that can greatly reduce the number of computations. Simulation and experimental results verify the effectiveness of the proposed capacitor voltage balancing method.