중금속 이온과 질소-황을 포함하는 포단드와의 착물형성에 관한 연구

정징운,이선하,최규성,강동현 慶南大學校 附設 基礎科學硏究所 1997 硏究論文集 Vol.10 No.-

The stability constant, enthalpy, and etropy changes of complexation of heavy metal ions (Zn²*, Cd²*) with podands containing nitrogen-sulfur donors such as tri(phenylthio-2-ethyl)amine (Podand Ⅰ), tri(benzylmercapto-2-ethyl)amine(Podand Ⅱ), and tetra(phenylthio-2-ethyl)ethylenediamine (Podand Ⅲ) have been determined by using potentiometric titration in 95% MeOH at various temperature. We observed the Podand Ⅲ ligand showed the largest protonation constant. The values of protonation constant and stability constant for Zn(Ⅱ), and Cd(Ⅱ) ions among three different ligands were increased as following order, Podand Ⅰ< Podand Ⅱ< Podand Ⅲ. In addition, thermodynamic parameters ΔH and TΔS of Zn(Ⅱ), Cd(Ⅱ) complexes have studied.

한국인 직무 스트레스 측정도구의 개발 및 표준화

장세진,고상백,강동묵,김성아,강명근,이철갑,정진주,조정진,손미아,채창호,김정원,김정일,김형수,노상철,박재범,우종민,김수영,김정연,하미나,박정선,이경용,김형렬,공정옥,김인아,김정수,박준호,현숙정,손동국 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

Background and Purposes: Over the past three decades, numerous studies performed in Korea have reported that job stress is a determinant risk factor for chronic diseases and work disability. Every society has its own culture and occupational climate particular to their organizations, and hence experiences different occupational stress. An occupational stress measurement tool therefore needs to be developed to estimate it objectively. The purpose of this study is to develop and standardize the Korean Occupational Stress Scale (KOSS) which is considered to be unique and specific occupational stressors in Korean employees. Subjects and Methods: Data were obtained from the National Study for Development and Standardization of Occupational Stress (NSDSOS Project: 2002-2004). A total of 12,631 employees from a nationwide sample proportional to the Korean Standard Industrial Classification and the Korean Standard Occupational Classification were administered. The KOSS was developed for 2 years (2002-2004). In the first year, we collected 255 items from the most popular job stress measurement tools such as JCQ, ERI, NIOSH and OSI, and 44 items derived from the a qualitative study (depth interview). Forty-three items of KOSS, in the second year, were retained for use in the final version of the KOSS by using Delphi and factor analysis. Items were scored using conventional 1-2-3-4 Likert scores for the response categories. Results: We developed eight subscales by using factor analysis and validation process: physical environment (3 items), job demand (8 items), insufficient job control (5 items), interpersonal conflict (4 items), job insecurity (6 items), organizational system (7 items), lack of reward (6 items), and occupational climate (4 items). Together they explained 50.0% of total variance. Internal consistency alpha scores were ranged from 0.51 to 0.82. Twenty-four items of the short form of the KOSS (KOSS-SF) were also developed to estimate job stress in the work setting. Because the levels of the subscales of occupational stress were gender dependent, gender-specific standard norms for both the 43-item full version and the 24-item short form using a quartile for the subscales of KOSS were presented. Conclusion: The results of this study suggest that KOSS might be an appropriate measurement scale to estimate occupational stress of Korean employees. Further and more detailed study needs to be conducted to improve the validity of this scale.

Investigating the Link Among LMA, FLLA, and Listening Comprehension of Chinese EFL Learners

Jing Sun(Jing Sun),Dong-Jin Shin(Dong-Jin Shin) 한국영어학학회 2024 영어학연구 Vol.30 No.1

Enhancing metacognitive awareness is considered an accelerating factor in listening skill development and empowers listeners’ autonomy. Anxiety is believed to be one of the affective factors that hinder the listening process the most. Previous studies have revealed that listening metacognitive awareness (LMA) and foreign language listening anxiety (FLLA) are related to listening performance. Interestingly, the interaction among LMA, FLLA, and English listening proficiency (ELP) in the context of English Major university students in China is not paid much attention to. This study examines the relationship among university students’ LMA, FLLA, and ELP. Besides, the impact of LMA and FLLA on the high- and low-proficiency groups of English listening is discussed. To this end, 276 English Major senior students were recruited to attend the experiment. To address the research questions, quantitative data analysis techniques, including descriptive statistics analysis, Pearson correlation, and Binary logistic regression, were run to analyze the data. Results reveal a significant positive correlation between the participants’ LMA and ELP. A significant and negative correlation between their FLLA and ELP is observed. Finally, LMA and FLLA both function significantly in grouping participants’ ELP into high- and low levels.

발효 고춧잎의 항산화 활성 평가

Jing Jing Li,Min-Sun Jeon,Hong-Sun Yook 한국생활과학회 2021 한국생활과학회 학술대회 Vol.2021 No.5

Endothelial Progenitor Cells’ Classification and Application in Neurological Diseases

Jing-jing Yuan,Jing Yang,Shi-lei Sun,Rui Zhang,Yu-ming Xu 한국조직공학과 재생의학회 2017 조직공학과 재생의학 Vol.14 No.4

The therapeutic effects of endothelial progenitor cells (EPCs) on ischemic stroke have been extensively studied in recent years. However, the differences in early EPCs and endothelial outgrowth cells (EOCs) are still unclear. Clarifications of their respective properties and specific functioning characteristics contribute to better applications of EPCs in ischemic diseases. In this review, we discuss cellular origin, isolation, culture, surface markers of early EPCs and EOCs and relevant applications in neurological diseases. We conclude that EOCs possess all characteristics of true endothelial progenitors and have potent advantages in EPC-based therapies for ischemic diseases. A number of preclinical and clinical applications of EPCs in neurological diseases are under study. More studies are needed to determine the specific characteristics of EPCs and the relevant mechanisms of EPCs for neurological diseases.

Abnormal Prefrontal Brain Activation During a Verbal Fluency Task in Treatment-Resistant Depression Using Near-Infrared Spectroscopy

Sun Jing-Jing,Shen Chen-Yu,Liu Xiao-Min,Liu Po-Zi 대한신경정신의학회 2023 PSYCHIATRY INVESTIGATION Vol.20 No.2

Objective The study investigated cognitive performance and brain function between treatment-resistant depression (TRD) and non- TRD patients to find potential neurobiological markers associated with refractoriness in depression patients.Methods Fourteen TRD patients, 26 non-TRD patients and 23 healthy controls (HC) were included in the present study. The neural function of prefrontal cortex (PFC) and cognitive performance among the three group were examined using near-infrared spectroscopy (NIRS) during verbal fluency task (VFT).Results Both TRD and non-TRD groups exhibited significantly worse VFT performance and lower activation of oxygenated hemoglobin (oxy-Hb) changes in the bilateral dorsolateral PFC (DLPFC) compared to the HC group. Within the TRD and non-TRD groups, VFT performance was no significant difference, but activation of oxy-Hb changes in dorsomedial PFC (DMPFC) in TRD patients was significantly lower than non-TRD patients. In addition, activation of oxy-Hb changes in right DLPFC were negatively correlated with the severity of depressive symptoms in depression patients.Conclusion Both TRD patients and non-TRD patients exhibited lower oxy-Hb activation in DLPFC. TRD patients exhibit lower oxy- Hb activation in DMPFC than non-TRD patients. fNIRS maybe a useful tool for predict depressive patients with or without treatment resistant.

A model for the electrical characteristics of metal-ferroelectric-insulator-semiconductor field-effect transistor

Jing Sun,Xue Jun Zheng,Wen Li 한국물리학회 2012 Current Applied Physics Vol.12 No.3

An improved theoretical model on the electrical characteristics of metal-ferroelectric-insulatorsemiconductor field-effect transistor (MFIS-FET) has been proposed by considering the historydependent electric field effect and the mobility model. The capacitanceevoltage (CeV) characteristics of MFIS structure is evaluated by combining the switching physics of ferroelectric with the silicon physics, and the drain current-gate voltage (ID-VGS) and drain current-drain voltage (ID-VDS) characteristics of MFIS-FET are modeled by combining the switching physics of ferroelectric with Pao and Sah’s double integral. For two MFIS-FETs with SrBi2Ta2O9 and (Bi,La)4Ti3O12 ferroelectric layers, the CeV, ID-VGS and ID-VDS characteristics are simulated by using the improved model, and the results are more consistent with the previous experiment than those based on Lue model, indicating that the improved model is suitable for simulating the electrical characteristics of MFIS-FET. This work is expected to provide some guidance to the design and performance improvement of MFIS structure devices.

Experimental investigation on the contribution of gas molecular diffusion to gas mass flux in micro-nano pores

Jing Sun,Dehua Liu,Xiang Zhu,Wenjun Huang,Liang Cheng 한국자원공학회 2020 Geosystem engineering Vol.23 No.1

The mass transfer from the matrix to the fracture face is driven by both concentration and pressure differences. In this work, high-temperature high-pressure (HPHT) systems for diffusion experiments with only concentration differences were used to determine the diffusion coefficient, and flow experiments with only pressure differences were also conducted; and the magnitude of gas molecular diffusion and its contribution to production were analyzed in this study. The results show as follows: (1) Gas flow from the matrix to the fracture system is driven by the combined effect of gas molecular diffusion and seepage. The pore structure characteristics of the reservoir and the contribution of the diffusion to the yield can vary greatly. (2) In tight reservoirs with an average permeability of 0.3067 mD, the contribution of gas molecular diffusion to the total gas mass flux is only 0.08%, while in shale reservoirs, the average permeability is 0.0015 mD; the contribution of diffusion to the total gas mass flux could be as large as 1%. (3) The contribution of molecular diffusion to gas production is closely related to the pore sizes of the porous medium. The smaller the pore sizes are, the greater the contribution of molecular diffusion to gas production.

Fast terminal sliding mode tracking control of hypersonic vehicles based on non-homogeneous disturbance observer

Jing-Guang Sun,Shen-Min Song,Hai-Tao Chen,Guan-Qun Wu 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.6

The tracking control problem of hypersonic vehicles is studied and analyzed in this paper using terminalsliding mode control method (TSMC) and non-homogeneous disturbance observer(NHDO) considering parametricuncertainty and external disturbances. Non-singular terminal sliding mode controller is provided based on NHDO. The key idea is that the NHDO is adopted to estimate the aerodynamic uncertainties and external disturbancessimultaneously, which can enhance the robustness of the system and lower the gain of the switch controller. Rigorousstability analysis for the closed-loop system is given via Lyapunov stability theory, which proves that thesystem states are always bounded even during the estimation process when the estimation error is not zero. Thesliding manifold can be reached in finite time and the tracking errors can converge to zero asymptotically. Numericalsimulations are conducted with the longitudinal nonlinear dynamic model of hypersonic vehicles to verify theeffectiveness and robustness of the designed controller.

A Study on Travel Preference of Jinan Group Tourists to South Korea

Sun, Jing,Zhang, Yuqi 한중경제문화학회 2016 한중경제문화연구 Vol.6 No.-

With the more frequent economic and cultural exchanges between China and South Korea, tourist arrivals to South Korea are also booming. The study on travel preference is significant to promote the tourist market and route design. This paper studies the group tourists from Jinan, Shandong province to South Korea, and analyzes their preferences on travel, motivation and consumption. It also studies whether the demographic variable has distinctive influences on travel preference. Finally it puts forwards the suggestions to improve the service and quality of group travellers to South Korea.