The Relatedness Between Graphene Oxide Lateral Size and the Mechanical Properties of Calcium Alginate Composite Fibers

Lijun Jin,Yiqi Wu,Xinjun Hu,Qinjia Chen,Yue Lu,Yongxiao Bai 한국섬유공학회 2023 Fibers and polymers Vol.24 No.2

It is widely recognized that combining alginate with graphene oxide (GO) is an effective method in improving the propertiesof alginate fiber. However, how the lateral size of GO influences the properties of the composite fiber is still unclear. Inthis work, GO was separated into four kinds of different lateral sizes with the assistance of centrifugation and high-powerultrasound. The tensile strength of calcium alginate/graphene oxide (CaAlg/GO) composite fiber increased with the lateralsize of GO. Surprisingly, the combination of large and small GO performed the superior reinforcement effect. The tensilestrength and Young’s modulus increased from 407.66 MPa and 13.87 GPa to 556.97 MPa and 20.57 GPa, respectively. Inaddition, the water absorption ability of CaAlg/GO composite fiber reduced with the decreasing of the lateral size of GO. With significantly improved mechanical properties and fine biocompatibility, the CaAlg/GO composite fibers may havepotential applications in the biotechnological, biomedical, and tissue engineering areas.

Simplifi ed Calculation Methods for Static Behaviors of Triple-Tower Suspension Bridges and Parametric Study

Lijun Jia,Chuan Zhang,Yang Jiang,Jin Cheng,Ru-Cheng Xiao 한국강구조학회 2018 International Journal of Steel Structures Vol.18 No.2

In this paper, simplifi ed formulas to determine the static behaviors of triple-tower suspension bridges were derived, including the formulas for the force of main cable, the defl ection of the stiff ening girder, the safety factor of anti-slipping on the saddle and the moment of the tower under the live load. Also, formulas were verifi ed by a fi nite element model for three triple-tower suspension bridges with main span of 1500, 2000 and 2500 m. In the end, a parametric study was performed to investigate the infl uence of sag to span ratio, ratio of side span to main span as well as the stiff ness of mid tower on the static performance using analytical method.

Experimental investigation of the mechanical behaviors of grouted crushed coal rocks under uniaxial compression

Jin, Yuhao,Han, Lijun,Meng, Qingbin,Ma, Dan,Wen, Shengyong,Wang, Shuai Techno-Press 2018 Geomechanics & engineering Vol.16 No.3

A detailed understanding of the mechanical behaviors for crushed coal rocks after grouting is a key for construction in the broken zones of mining engineering. In this research, experiments of grouting into the crushed coal rock using independently developed test equipment for solving the problem of sampling of crushed coal rocks have been carried out. The application of uniaxial compression was used to approximately simulate the ground stress in real engineering. In combination with the analysis of crack evolution and failure modes for the grouted specimens, the influences of different crushed degrees of coal rock (CDCR) and solidified grout strength (SGS) on the mechanical behavior of grouted specimens under uniaxial compression were investigated. The research demonstrated that first, the UCS of grouted specimens decreased with the decrease in the CDCR at constant SGS (except for the SGS of 12.3 MPa). However, the UCS of grouted specimens for constant CDCR increased when the SGS increased; optimum solidification strengths for grouts between 19.3 and 23.0 MPa were obtained. The elastic moduli of the grouted specimens with different CDCR generally increased with increasing SGS, and the peak axial strain showed a slightly nonlinear decrease with increasing SGS. The supporting effect of the skeleton structure produced by the solidified grouts was increasingly obvious with increasing CDCR and SGS. The possible evolution of internal cracks for the grouted specimens was classified into three stages: (1) cracks initiating along the interfaces between the coal blocks and solidified grouts; (2) cracks initiating and propagating in coal blocks; and (3) cracks continually propagating successively in the interfaces, the coal blocks, and the solidified grouts near the coal blocks. Finally, after the propagation and coalescence of internal cracks through the entire specimens, there were two main failure modes for the failed grouted specimens. These modes included the inclined shear failure occurring in the more crushed coal rock and the splitting failure occurring in the less crushed coal rock. Both modes were different from the single failure mode along the fissure for the fractured coal rock after grouting solidification. However, compared to the brittle failure of intact coal rock, grouting into the different crushed degree coal rocks resulted in ductile deformation after the peak strength for the grouted specimens was attained.

Scalable Coding of Depth Images with Synthesis-Guided Edge Detection

( Lijun Zhao ),( Anhong Wang ),( Bing Zeng ),( Jian Jin ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.10

This paper presents a scalable coding method for depth images by considering the quality of synthesized images in virtual views. First, we design a new edge detection algorithm that is based on calculating the depth difference between two neighboring pixels within the depth map. By choosing different thresholds, this algorithm generates a scalable bit stream that puts larger depth differences in front, followed by smaller depth differences. A scalable scheme is also designed for coding depth pixels through a layered sampling structure. At the receiver side, the full-resolution depth image is reconstructed from the received bits by solving a partial-differential-equation (PDE). Experimental results show that the proposed method improves the rate-distortion performance of synthesized images at virtual views and achieves better visual quality.

A Study of the Effect of Work-Family Culture on Employee Work-Family Enrichment

Zhang, Lijun(장려군),Chung, Soo-Jin(정수진) 한국경영교육학회 2018 경영교육연구 Vol.33 No.2

[연구목적] 본 연구는 중국의 일반적인 직원들을 대상으로 하여 진행하였다. 연구의 목적은 일-가정 문화가 일-가정 이익에 미치는 영향에 대하여 검증하고, 일-가정 문화가 일-가정 이익에 영향을 미치는 과정에 일몰입의 매개역할과 자기효능감의 조절역할에 대해 검증하는 것이다. [연구방법] 본 연구는 선행연구를 토대로 하여 여섯 개 가설을 제기하였다. 이를 위해 일반적인 직원을 대상으로 설문조사를 실시하였다. 통계분석 프로그램 SPSS 23.0과 AMOS 23.0을 통해 수집된 자료로 가설을 검증하였다. [연구결과] 첫째, 일-가정 문화가 일-가정 이익에 유의적인 영향을 미치는 것으로 확인 되었다. 둘째, 일-가정 문화가 일-가정 이익에 영향을 미치는 과정에서 일몰입의 유의적인 매개효과가 확인되었다. 셋째, 일-가정 문화가 일-가정 이익에 영향을 미치는 과정에서 자기효능감의 조절효과가 확인되었다. [연구의 시사점] 선행연구에서 일-가정 문화와 종업원의 일-가정 관계에 대해 주요하게 일-가정 갈등이라는 부정적인 개념에 치중한 점을 보완하였고 긍정적인 결과에 대한 연구를 충족시켰다. 중국 국내의 기업들에 있어서 긍정적인 시점으로부터 출발하여 종업원의 일-가정 문화가 일-가정 증익에 대한 효과기제와 종업원 개인의 차이를 토대로 하여 일-가정 증익의 실현에 효과적인 방법을 제공한다. [Purpose] This research takes ordinary Chinese employee as the research object. The purpose of the study is to explore the impact of work-family culture on work-family enrichment, and thereby verify the mediating effect of work-engagement and the moderating effect of self-efficacy. [Methodology] Based on the related research, this study proposes six hypotheses. A total of 380 valid questionnaires were collected from the general employee in China by means of a questionnaire. Data were analyzed by using SPSS 23.0 and AMOS 23.0 software. [Findings] Firstly, work-family culture has a significant and direct impact on the employee’s work-family enrichment. Secondly, work-engagement plays a mediating effect in process of influencing by the work-family culture on the work-family enrichment. Thirdly, self-efficacy plays a moderating role in process of influencing by the work-family culture on the work-family enrichment. [Implications] In contrast to past research on work-family culture and employee work-family relations, which mainly focused on the negative aspects of work-family conflicts, the study attempts to enrich the research on positive results.

Hole dephasing caused by hole–hole interaction in a multilayered black phosphorus

Li, Lijun,Khan, Muhammad Atif,Lee, Yoontae,Lee, Inyeal,Yun, Sun Jin,Youn, Doo-Hyeb,Kim, Gil-Ho IOP 2017 Journal of physics, an Institute of Physics journa Vol.29 No.43

<P>We study the magnetotransport of holes in a multilayered black phosphorus in a temperature range of 1.9 to 21.5 K. We observed a negative magnetoresistance at magnetic fields up to 1.5 T. This negative magetoresistance was analyzed by weak localization theory in diffusive regime. At the lowest temperature and the highest carrier density we found a phase coherence length of 48 nm. The linear temperature dependence of the dephasing rate shows that the hole–hole scattering processes with small energy transfer are the dominant contribution in breaking the carrier phase coherence.</P>

Reproducibility of an intraoral scanner: A comparison between in-vivo and ex-vivo scans

Sun, LiJun,Lee, Jin-Sol,Choo, Hyun-Hee,Hwang, Hyeon-Shik,Lee, Kyung-Min Elsevier 2018 American journal of orthodontics and dentofacial o Vol.154 No.2

<P><B>Introduction</B></P> <P>The purpose of this study was to assess the reproducibility of in-vivo and ex-vivo scans using an intraoral scanner.</P> <P><B>Methods</B></P> <P>Twenty adults with no missing teeth except for third molars were included in the study. Alginate impressions were taken, and plaster models were made from the impressions. Each subject underwent full-arch intraoral scanning twice with a TRIOS scanner (3Shape, Copenhagen, Denmark) at an interval of 2 weeks, and, the plaster models were scanned at the same interval with the same scanner. The first images of each scan were superimposed on the second scanned images using surface-based registration. In each case, the differences between the 2 scanned images were evaluated with color mapping. The reproducibility between the in-vivo and ex-vivo scans was compared using independent <I>t</I> tests and Bland-Altman analysis.</P> <P><B>Results</B></P> <P>The discrepancies between the first and second images were greater in the posterior than in the anterior regions for both the in-vivo and ex-vivo scans. Average surface differences between the first and second images were greater for the in-vivo scans (0.04 mm) than for the ex-vivo scans (0.02 mm). The Bland-Altman plots showed that the reproducibility of both scans was within the limits of agreement.</P> <P><B>Conclusions</B></P> <P>The reproducibility of in-vivo scanning was comparable with ex-vivo scanning, although it showed a slight difference (0.02 mm) compared with ex-vivo scanning.</P> <P><B>Highlights</B></P> <P> <UL> <LI> In-vivo intraoral scanning showed a 0.041-mm average mean difference between 2 scans. </LI> <LI> Ex-vivo intraoral scanning showed a 0.019-mm average mean difference between 2 scans. </LI> <LI> Reproducibility of in-vivo scanning was similar to that of ex-vivo scanning. </LI> </UL> </P>

Synthesis and Characterization of Folic Acid Labeled Upconversion Fluorescent Nanoprobes for in vitro Cancer Cells Targeted Imaging

Ming Huang,Lijun Wang,Xiaojuan Zhang,Jin Zhou,Lihua Liu,Yuefang Pan,Bin Yu,ZHANGSEN YU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.5

Upconversion nanoparticles (UCNPs) are widely used in the field of biomedicine, such as biosensing, cell labeling and medical multimodal imaging because of their unique optical properties. In this paper, we demonstrated the synthesis of polyethylenimine-modified NaLuF4:Yb,Er (RE = Lu 0.78, Yb 0.18, Er 0.02) UCNPs in three different solvents, such as water, ethylene glycol and diethylene glycol. The as-prepared UCNPs were characterized and the experimental results showed that the UCNPs synthesized in ethylene glycol had excellent properties. The obtained UCNPs in ethylene glycol had the smallest particle size and uniform size distribution, and the pure cubic phase of crystallization and Dynamic light scattering and particle dispersion index (DLS/Pdi) were the smallest. What's more, the upconversion fluorescence intensity was 7 and 52 times greater than that of UCNPs synthesized in diethylene glycol and water, respectively. In addition, the factors of reaction solvent that had an impact on the particle size, morphology, crystalline phase, DLS and upconversion fluorescence intensity of the synthesized UCNPs were discussed. Moreover, in order to obtain the targeted nanoprobe, we used an EDC/NHS covalent coupling method to modify folic acid to the NaLuF4:Yb,Er/PEI UCNP surface. The NaLuF4:Yb, Er/PEI–FA upconversion fluorescent nanoprobes had low cytotoxicity and were suitable for the application in HeLa cells targeted fluorescent imaging.

Analysis of Arabidopsis Transcription Factor Families Revealed Extensive Capacity for Cell-to-Cell Movement as Well as Discrete Trafficking Patterns

Yeonggil Rim,Lijun Huang,Hyosub Chu,Xiao Han,조원경,Che Ok Jeon,Hye Jin Kim,홍종찬,윌리엄루카스,김재연 한국분자세포생물학회 2011 Molecules and cells Vol.32 No.6

In plants, cell-to-cell communication is pivotal for the orchestration of cell fate determination, organ develop-ment, and the integration of whole plant physiology. One of the strategies for intercellular communication uses symplasmic communication channels, called plasmodes-mata (PD). These PD establish unique cytoplasmic chan-nels for the intercellular exchange not only of metabolites and small signaling molecules, but also of regulatory proteins and RNAs to allow for local orchestration of development and physiology. A number of non-cell-autonomous transcrip-tion factors (NCATFs) have been shown to function in the coordination of specific regulatory networks. To further explore the potential of such NCATFs, a genome-wide screen was performed on the transcription factor (TF) families in Arabidopsis. We here report that, among the 76 TFs examined, 22 were shown to move beyond their sites of transcription in the root apex; these NCATFs belonged to 17 TF families, including homeobox, GRAS, and MYB. Expression studies performed on variously-sized mCherry constructs identified a range of PD size exclusion limits within tissues of the root. In addition, our studies showed that actual protein level was an important factor controlling the range of TF intercellular movement. Interestingly, our studies on CAPRICE move-ment revealed tissue-speci-ficity with respect to the mode of intercellular trafficking. These findings are discussed with respect to the regulation between cell-autonomous or non-cell-autonomous action.

X500R QTOF System with SWATH<SUB>®</SUB> Acquisition for Pesticide Residue Screening in Fruits and Vegetables

Xiaojing Sun,Haiyan Cheng,Lijun Li,Wenhai Jin,Kim, Woobok(김우복) 한국농약과학회 2018 한국농약과학회 학술발표대회 논문집 Vol.2018 No.4