Kinetics of the Formation of Metalloporphyrins and the Catalytic Effect of Lead Ions and Hydrogen Ions

Yong Qi,Ji Gang Pan 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.11

The reaction mechanism of Lead ions catalyzing complexation reactions between TIPP and metal ions was investigated by researching the kinetics of the formation of metalloporphyrins by UV/Vis-spectra, and verified by exploring the formation of metalloporphyrins catalyzed by acetic acid. Kinetics studies suggested that the fluctuations of reaction rate indicated the formation of metalloporphyrin was step-wise, including the preequilibrium step (the coordination of the pyrrolenine nitrogens to Mn+) and the rate-controlling step (the deprotonation of the pyrrole proton). In the pre-equalization step, a sitting-atop (SAT) structure formed first with the complexation between larger radius of Pb2+ and TIPP, changed the activation, then Pb2+ left with the smaller radius of metal ions attacking from the back of the porphyrin ring center. In the rate-controlling step, two pyrrole protons dissociated to restore a stable structure. This was verified by adding acetic acid at different reaction times.

Driving forces and structural changes of China as a market provider for Korea An input-output analysis

Yongqi Feng,Tianshu Zhang 한국무역학회 2018 Journal of Korea trade Vol.22 No.3

Purpose – The purpose of this paper is to provide a better understanding of the driving forces and structural changes of China as a market provider for Korea. This paper gives the answers for the following questions: How do China’s final demands trigger the growth of its imports from Korea? And what’s the impact of China’s final demands on the import in different industries? Design/methodology/approach – Based on the Multi-Regional Input-Output model and World Input-Output Table database, this paper constructs the non-competitive imports input-output (IO) table of China to Korea. According to this table, we can calculate the induced imports coefficient and comprehensive induced import coefficients of China’s four final demands for imports from Korea in the 56 industries in China. Findings – Among the four driving forces, the strongest one is changes in inventories and valuables. The impact of final consumption expenditure and fixed capital formation is much lower than that of changes in inventories and valuables, but they have a broader impact for the 56 industries. This paper finds out the China’s import induction of the final demands to Korea peaked in 2005 and 2010 and decreased greatly in 2014, so the position of China as market provider for Korea will no longer rise substantially, contrarily it will be in a steady state. Originality/value – First, this paper constructs the non-competitive IO table to analyze the market provider issues between two countries and provides practical ways and methods for studies on the issues of imports and market provider. Second, this paper investigates the different roles of four final demands on driving force of China as market provider for Korea and the structural changes of China as a market provider for Korea among 56 industries from 2000 to 2014.

Efcient and Stable Ideal Bandgap Perovskite Solar Cell Achieved by a Small Amount of Tin Substituted Methylammonium Lead Iodide

Yongqi Yin,Sufang Fu,Sheng Zhou,Yuling Song,Lin Li,Mingyi Zhang,Jie Wang,Pandiyarajan Mariyappan,Saad M. Alshehri,Tansir Ahamad,Yusuke Yamauchi 대한금속·재료학회 2020 ELECTRONIC MATERIALS LETTERS Vol.16 No.3

Ideal bandgap ~1.4 eV of lead–tin (Pd–Sn) organic–inorganic hybrid perovskite absorber is essential to further enhance thepower conversion efciency of perovskite solar cells (PVSCs). However, due to the facile oxidation of Sn2+, large amount ofSn substituted Pb based PVSCs sufer with low stability in ambient environment. In this work, we realize an ideal bandgapperovskite by introducing a small amount (10 mol%) of Sn2+ to methylammonium lead iodide (MAPbI3). A large grain sizeMAPb0.9Sn0.1I3 flms with strong absorbance can be obtained. As a result, the best performance up to 18.3% efciency isachieved. Importantly, the MAPb0.9Sn0.1I3 cell retains 90% of its performance after operation at the maximum power pointunder full 1-sun illumination for 500 h, in contrast to the quick degradation of MAPbI3 cell. This study demonstrates thepromising potential of stable and efcient ideal band-gap Pb–Sn PVSCs.

Contribution of Pseudolite Observations to GPS Precise Surveys

Yongqi Chen,Xiufeng He 대한토목학회 2008 KSCE JOURNAL OF CIVIL ENGINEERING Vol.12 No.1

Although GPS has been widely used for precision surveys, many survey environments, like in urban areas, deep open-pit minesand valleys, limit the number of visible GPS satellites, deteriorating the survey accuracy. In addition some engineering projectsrequire higher positioning accuracy in a particular direction. A GPS-only system hardly satisfies the requirements. Pseudolite-augmented GPS survey technique can strengthen the positioning geometry. Pseudolite (PL) measurements, however, suffer fromvarious sources of errors different from GPS observations. In order to employ them fo mustbe treated properly. This paper discusses of the major sources of errors in PL measurements and the methodologies for theirmitigation. Some experimental tests are then presented.

Current Status and Challenges of Flower Industry in China

Zheng Yongqi 한국원예학회 2017 한국원예학회 학술발표요지 Vol.2017 No.10

China as Market Provider for OBOR Countries

FENG Yongqi,ZHANG Tianshu 한국무역학회 2017 한국무역학회 국제학술대회 Vol.2017 No.11

韧性城市理念下水边公园设计特征分析

袁永奇 ( Yuan Yongqi ),金利炫 ( Rihyun Kim ),吴秀贤 ( Soohyun Oh ),尹甲根 ( Gabgeun Yoon ) 인문사회 21 2023 인문사회 21 Vol.14 No.1

研究目的: 本研究旨在结合韧性城市理念, 通过水边公园的设计, 作为城市景观和公共空间, 在解决城市减灾防灾并最终实现可持续发展为主要目的, 探讨韧性水边公园的设计方法。 研究方法: 通过对韧性城市和水边公园进行先行研究, 得出了为了实现韧性城市水边公园设计的特征和必要性, 并得出韧性水边公园的特性。 研究内容: 通过案例调查对中国4个韧性水边公园的设计特征进行分析, 分析在不同地区韧性水边公园的设计方法与策略。 结论及建议: 分析结果显示, 韧性水边公园是基于自然生态系统的基础上, 通过正确的人工开发, 实现自然生态与社会之间的平衡, 通过自然生态系统适应和循环能力, 提高水边空间防灾减灾能力, 减少潜在威胁, 确保城市的可持续发展。 This study aims to explore the design method of resilient waterfront park based on the design of resilient city concept, as an urban landscape and public space, with the main purpose of solving urban disaster reduction and finally realizing sustainable development. The necessity and design characteristics of resilient city and waterfront park design are obtained. Through case analysis of four waterfront parks in China, the design characteristics of resilient waterfront parks in different regions are summarized. According to the analysis results, the resilient waterfront park is based on the correct artificial development to realize the balance between the natural ecology and the society, and to use the adaptation and recycling capacity of the natural ecosystem to ensure the sustainable development of the city.

GPS Satellite Orbit Prediction Based on Unscented Kalman Filter

Zuoya ZHENG,Yongqi CHEN,LU Xiushan,DU Zhixing 한국항해항만학회 2006 한국항해항만학회 학술대회논문집 Vol.1 No.-

In GPS Positioning, the error of satellite orbit will affect user’s position accuracy directly, it is important to determine the satellite orbit precise. The real-time orbit is needed in kinematic GPS positioning, the precise GPS orbit from IGS would be delayed long time, so orbit prediction is key to real-time kinematic positioning. We analyze the GPS predicted ephemeris, on the base of comparison of EKF and UKF, a new orbit prediction method is put forward based on UKF in this paper, the result shows that UKF improves the orbit predicted precision and stability. It offers a new method for others satellites orbit determination as Galileo, and so on.

Effective transmission screw nuts of steel backing/self-lubricating composite lining fabricated by injection molding

Yousong Sun,Chunmei Li,Yongqi Cheng,Liangmo Wei 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.1

To increase transmission efficiencies and bearing abilities of sliding screw pairs, a new type of screw nuts and their fabricating method were put forward. The nuts have the structure of steel backing/self-lubricating composite lining with the advantages of high bearing capacity and low friction coefficient. The lining material was composed of epoxy as the matrix and some additives: carbon fiber, graphite, MoS2, firming agents and coupling agents etc. A suitable formulation was determined by experiments to meet lining requirements: high bounding strength, sufficient mechanical properties and good tribological properties. An injection molding set for fabricating the nut linings was designed and made to achieve even lining thickness along the thread surfaces during molding. Lubrication grooves on the nut thread surfaces were created during molding. In comparison with bronze ZQSn6-6-3, the friction coefficient of the composite nuts was reduced by 35% and the transmission efficiency increased by 30%.

Sulfidation and regeneration of iron-based sorbents supported on activated-chars prepared by pressurized impregnation for coke oven gas desulfurization

Jianglong Yu,Jinxiao Dou,Yongqi Zhao,Arash Tahmasebi 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.10

The sulfidation and regeneration properties of lignite char-supported iron-based sorbent for coke oven gas (COG) desulfurization prepared by mechanical stirring (MS), ultrasonic assisted impregnation (UAI), and high pressure impregnation (HPI) were investigated in a fixed-bed reactor. During desulfurization, the effects of process parameters on sulfidation properties were studied systematically. The physical and chemical properties of the sorbents were analyzed by X-ray diffraction (XRD), scanning electron microscope coupled with energy dispersive spectroscopy (SEM-EDS), Fourier transform infrared (FTIR) and BET surface area analysis. The results of desulfurization experiments showed that high pressure impregnation (HPI) enhanced the sulfidation properties of the sorbents at the breakthrough time for char-supported iron sorbents. HPI method also increased the surface area and pore volume of sorbents. Sulfur capacity of sorbents was enhanced with increasing sulfidation temperatures and reached its maximum value at 400 oC. It was observed that the presence of steam in coke oven gas can inhibit the desulfurization performance of sorbent. SO2 regeneration of sorbent resulted in formation of elemental sulfur. HPIF10 sorbent showed good stability during sulfide-regeneration cycles without changing its performance significantly.