SURFACE MODIFICATION AND CHARACTERIZATION OF Fe_3O_4/Au COMPOSITE NANOPARTICLES

FENG SHI,WENLI HUI,YALI CUI,CHAO CHEN 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2011 NANO Vol.6 No.2

Fe_3O_4/Au composite nanoparticles were modified with α-thio-ω-carboxy poly (ethylene glycol). Results from XRD, selected area diffraction, high-resolution TEM images, and dynamic lighting scattering illustrate that the particles have a core/shell composite structure and were monodispersed. Surface plasmon resonance measured by UV–Vis indicates that the absorption peak of the modified composite particle characteristic at 532 nm can be stably suspended in a different buffer. The modified composite particles also have good response to external magnetic field. The Fe_3O_4/Au composite nanoparticles are magnetically and optically active, and are useful for simultaneous magnetic and optical detection. Coupled with biomolecules, the advantages of these composite particles make them very promising for biomedical applications in the near future.

Transcriptomic and proteomic profiling revealed global changes in Streptococcus thermophilus during pH-controlled batch fermentations

Yali Qiao,Cong Leng,Gefei Liu,Yanjiao Zhang,Xuepeng Lv,Hongyu Chen,Jiahui Sun,Zhen Feng 한국미생물학회 2019 The journal of microbiology Vol.57 No.9

Understanding global changes of physiological processes at the molecular level during the growth of Streptococcus thermophilus is essential for the rational design of cultivation media and the optimization of bioprocesses. Transcriptomics and proteomics were combined to investigate the global changes at the transcript and protein level during the growth of S. thermophilus. The expression of 1396 genes (FDR ≤ 0.001) and 876 proteins (P < 0.05) changed significantly over time. The most remarkable growth phase dependent changes occurred in the late-lag phase and were related to heterofermentation, glycolysis, peptidoglycan biosynthesis, conversion between amino acids and stress response. The present results could provide theoretical guidance for high-cell-density culture, help design cultivation media, and help attain a high biomass of S. thermophilus.

How Competitive Orientation Influences Unethical Decision-making in Clinical Practices?

Yali Li,Taiwen Feng,Wenbo Jiang 한국간호과학회 2018 Asian Nursing Research Vol.12 No.3

Purpose: This study aims to investigate how competitive orientation influences unethical decisionmaking (UDM) through relationship conflict and the moderating effect of hostile attribution bias. Methods: This study was conducted using a self-report questionnaire. Data were collected from 727 employees in Chinese hospitals. For each variable, measures were adopted or adapted from existing literature. Data were analyzed using descriptive statistics, correlation analysis, confirmatory factor analysis, and hierarchical regression analysis. Common method variance was established using Harman's single-factor test. Results: Competitive orientation is significantly and positively associated with relationship conflict (b = .36, p < .001) and UDM (b = .35, p < .001). Relationship conflict is significantly and positively associated with UDM (b = .51, p < .001). Relationship conflict partially mediates the relationship between competitive orientation and UDM. In addition, hostile attribution bias strengthens the positive relationship between competitive orientation and UDM through relationship conflict. Conclusion: This study provides some implications for hospital employees to deal with ethical dilemmas in decision-making. Hospital employees including nurses, physicians, and other health-care professionals should raise awareness of competitive orientation and adopt a cooperative approach to human relations. Effective training programs should be utilized to direct all hospital employees to depress hostile attribution bias whenever possible to everything in clinical practice.

WHEN GRATITUDE BACKFIRES: HOW CULTURE SHAPES THE CONSUMER SATISFACTION

Yali Fan,Rong Chen,Feng He 글로벌지식마케팅경영학회 2018 Global Marketing Conference Vol.2018 No.07

This paper examines the impact of thanks from the sellers on consumer satisfaction in the tourism industry. Study 1 shows that thanks from the sellers (vs. no thank from the sellers) will decrease consumer satisfaction. In this process, perceived fairness and perceived value play a serial mediation role. Study 2 shows that the pricing type (the fixed price vs. the flexible price) plays a moderate role on the impact of thanks from the sellers at the end of a transaction on consumer satisfaction. This paper introduces transaction utility theory and culture difference to explain the seemingly inconsistent phenomenon. Introduction The present studies focus on retailers expressing gratitude and, especially, how the communication of retailer expressing gratitude or not affects consumer satisfaction under the tourism purchase environment. Image that you encounter a seller is selling the souvenirs in the tourist spot you just visit, you would like to buy one of the souvenirs, such as a special cup with the souvenirs logo, you conclude a deal with the seller eventually, after that, the seller thanks for your purchasing and you leave. One question arises, will consumers feel less satisfaction when sellers say nothing than when they say “Thank you” at the end of a transaction? Theoretical Background Thanking is one of the speech acts or communicative acts frequently and abundantly utilized in human interactions, even though, most of these studies have focused on a western perspective, little is known about the experience of tourists from Asia. In western countries, people are accustomed to saying thank you after the benefit of others. Some behavioral responses may resemble the expression of gratitude (e.g., saying thank you to a waiter in a restaurant), but may instead be an automatic polite response not grounded in emotion (Buck 2004; Emmons and McCullough 2003; Fazalehasan et al 2017). However, in Somali and China culture, people are not used to expressing thanks, which makes many Americans or Australian feel rude or impolite (Chiu and Hong 2013; Robertson 2014). Here we test the prediction that gratitude from retailers may affect consumer satisfaction in a potentially counterintuitive manner. In other words, we hypothesize that gratitude from the retailer may lead to lower consumer satisfaction. This prediction draws from both the existing literature on gratitude as well as from research on culture difference and transaction utility theory from the response to gratitude. Research Design Two experiments have been conducted to test the hypotheses. Study 1 will provide support for the three central hypotheses regarding perceived fairness inference (hypothesis 1), perceived value inferences (hypothesis 2), and consumer satisfaction (hypothesis 3). Study 2 will test an important boundary condition. This study shows that the proposed negative effect of saying thank you (vs. saying nothing) holds only if the price of product is fixed. Result and Conclusion In the study 1, we found that sellers saying thank you after the transaction leads to less consumer satisfaction. Therefore, an important contribution of our work emerges from our melding of the literature on perceived fairness and value and demonstrating that gratitude from the sellers dictates which literature is more applicable in relationship marketing. Furthermore, we also examined the mechanism in study 2 and explore a boundary condition. We discovered that when the price of a souvenir is fixed, consumers feel more satisfaction when sellers say nothing than when they say “Thank you” at the end of a transaction. Conversely, when the price of a souvenir is not fixed, which is to say when consumers can bargain in the store, consumers feel less satisfaction when sellers say nothing than when they say “Thank you” after the transaction

The Impact of Self-Efficacy on Nurses’ Well-Being: Does Digital Competence Matter?

Li, Yali,Jing, Qi,Feng, Taiwen,Yang, Xiaoling 한국간호과학회 2023 Journal of Korean Academy of Nursing Vol.53 No.4

Effective separation of Zn, Fe, and Mn from roasting-water leaching solution of blast-furnace dust using a precipitation-solvent extraction process

Jinrong Ju,Yali Feng,Haoran Li,Ben Wang 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.12

Selective extraction of Zn from blast furnace dust can be achieved by the ammonium sulfate roasting-waterleaching process. An innovative method for effective separation of Zn, Fe, and Mn from roasting-water leaching solutionof blast-furnace dust by precipitation-solvent extraction process is proposed in this research. The Fe of leachingsolution was selectively converted into FePO4·2H2O precipitate by using Na2HPO4 as precipitant. The precipitation efficiencyof Fe reached 99.17%, while that of Zn was only 0.20% under the solution pH of 2.2, molar ratio of Na2HPO4 toFe of 1.2 : 1, reaction temperature of 30 oC, and reaction time of 50 min. The zinc in the filtrate was extracted with Cyanex302, and Zn (99.94%) was extracted through two-stage countercurrent extraction under initial pH of 3.4, Cyanex302 concentration of 25%, and O/A of 2 : 1. Subsequently, Zn (99.96%) of the organic phase was stripped using 0.75mol/L sulfuric acid by one-stage countercurrent stripping. Furthermore, according to thermodynamic calculation, it isproved that extracting Zn from sulfuric acid solution with Cyanex 302 is an exothermic reaction. The proposed processflowsheet may be used to efficiently recover Zn and Fe from blast-furnace dust.

Separation of Cu, Co, Ni and Mn from acid leaching solution of ocean cobalt-rich crust using precipitation with Na2S and solvent extraction with N235

Ju Jinrong,Yali Feng,Haoran Li,Hao Wu,Shunliang Liu,Chenglong Xu,Xin Li 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.3

In order to effectively separate and recover copper, cobalt, nickel and manganese from the leaching solution of ocean cobalt-rich crusts, a process of selective precipitation and extraction using precipitation with Na2S solution and solvent extraction with N235 extractant, was proposed. The optimum separation and recovery process conditions were determined through single factor condition experiments. The results show the precipitation efficiency of copper can reach 99.87%, while the precipitation efficiency of cobalt and nickel was 1.23% and 1.08%, respectively, at the initial pH of 0.60. Similarly, under the condition of initial pH of 4.00, 99.18% cobalt and 98.31% nickel were precipitated and only 0.89% manganese was co-precipitated. The mixed cobalt-nickel precipitation was completely dissolved with HCl solution, then N235 extractant was used to extract cobalt from solution. The extraction efficiency of cobalt can exceed 99% though three stages countercurrent extraction under optimal extraction conditions (chloride ion concentration of 9mol/L, the N235 concentration of 30% (v/v), the phase ratio (O/A) of 2, and at 298.15 K for 8min). In addition, thermodynamic calculations showed that the extraction of cobalt from acid leaching solution of ocean cobaltrich crust with N235 as the extractant was an exothermic reaction.

Investigation on the mechanism of ring formation in the process of NaCl recovery by pyrolysis of chemical waste salt using rotary kiln

Wenyuan Wang,Yali Feng,Haoran Li,ShunLiang Liu,Jinrong Ju,Yi Yang,Ben Wang 대한환경공학회 2023 Environmental Engineering Research Vol.29 No.3

Chemical waste salt is a hazardous waste generated during chemical production, and it is crucial to complete the recycling of the waste salt in a practical way. In the case of waste salt recycling by rotary kiln pyrolysis carbonization, ringing affects the pyrolysis efficiency and process running, thus a study on waste salt ringing was conducted. The results showed that the particle size is the key to the ring formation in rotary kiln, and pyrolysis temperature, pyrolysis time and temperature distribution in the rotary kiln also affect the material discharge rate during pyrolysis of waste salt in the rotary kiln. Thermogravimetric analysis and SEM images revealed that the volatilization of organic matter in the material due to pyrolysis caused a decrease in the abrasion resistance of the waste salt particle, which was the factor behind the ringing during pyrolysis in the rotary kiln. This study may provide a reference for the implementation of similar waste salt pyrolysis carbonization processes.