Buckling analysis of elastically-restrained steel plates under eccentric compression

Ying Qin,Gan-Ping Shu,Er-Feng Du,Rui-Hua Lu 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.29 No.3

In this research, the explicit closed-form local buckling solution of steel plates in contact with concrete, with both loaded and unloaded edges elastically restrained against rotation and subjected to eccentric compression is presented. The Rayleigh-Rize approach is applied to establish the eigenvalue problem for the local buckling performance. Buckling shape which combines trigonometric and biquadratic functions is introduced according to that used by Qin <i>et al</i>. (2017) on steel plate buckling under uniform compression. Explicit solutions for predicting the local buckling stress of steel plate are obtained in terms of the rotational stiffness. Based on different boundary conditions, simply yet explicit local buckling solutions are discussed in details. The proposed formulas are validated against previous research and finite element results. The influences of the loading stress gradient parameter, the aspect ratio, and the rotational stiffness on the local buckling stress resultants of steel plates with different boundary conditions were evaluated. This work can be considered as an alternative to apply a different buckling shape function to study the buckling problem of steel plate under eccentric compression comparing to the work by Qin <i>et al</i>. (2018), and the results are found to be in consistent with those in Qin <i>et al</i>. (2018).

Inkjet Printed Quantum Dots Color Conversion Layers for Full-color Micro-LED Displays

Feng Qin,Cao Liu,Wenhui Wu,Wenxiang Peng,Sitao Huo,Jiandong Ye,Shulin Gu 대한금속·재료학회 2023 ELECTRONIC MATERIALS LETTERS Vol.19 No.1

With the ever-growing demands for larger size and high resolution displays, Micro-light-emitting diode (Micro-LED) displaywith quantum dots (QDs) fi lm as color conversion layers (CCLs) has become one of the most promising candidates offuture display for its advantages in low power consumption and wide color range. In this study, we report a novel full-colordisplay based on blue Micro LED, which has patterned red and green QDs color conversion (QDCC) layers fabricated byinkjet printing (IJP). A structure of double-layer bank was designed to reduce color deviation, prevent crosstalk, and fl attenthe QDCC layer. By optimizing the thickness of the red/green QDCC layers and the wavelength of blue Micro LEDbacklights, a full-color QDCC-LED display with 228 PPI resolution and size of 1.11-inch was successfully fabricated andshowed superb performance. We not only eff ectively reduced crosstalk, but also improved the color conversion effi ciency ofQDs. In addition, this QDCC-LED display prepared by embedded bonding process shows a color gamut of 107.53% NTSC.

Estimation and compensation for deviation of contour in slow tool servo precision turning for complicated curved surface

Feng-Ze Qin,Jian-Wei Ma,Zhen-Yuan Jia,Guan-Lin Li,Jian-Zhou Zhang 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.8

In the presence of extremely high precision turning the complicated curved surface with geometry features of large slope gradient and multi convex-concave characteristics, the micron-scale deviation of contour resulting from the tracking deviation of the feed axis becomes non-negligible. To diminish the micron-scale contouring deviation, this study presents a valid contouring error estimation and pre-compensation method for slow tool servo (STS) precision turning. Aiming at estimating the tracking deviation of the axis of the turning machine tool in the machining process, the steady-state tracking deviation model of the axis is first constructed. The proposed multiply tangential estimation method is derived from the Taylor series of the foot point. Since the rotation feed movement of the C axis is the main movement in cutting forming movement for STS turning machining, the monotonicity of the displacement for the C axis is ensured. The compensation value for the axis position is derived through the Jacobi matrix of the STS turning machine. With the presented approach, the tool tip location deviation induced by the tracking deviation of the feed axis reduces from 1.087 μm to 0.025 μm. The measurement results of the comparison experiments indicate that with the presented method in this study, the contouring error of the machined part reduces from 5.72 μm to 4.36 μm. The micron-scale contouring error resulting from the tracking deviation of the feed axis is effectually compensated.

Selective miRNA Expression Profile in Chronic Myeloid Leukemia K562 Cell-derived Exosomes

Feng, Dan-Qin,Huang, Bo,Li, Jing,Liu, Jing,Chen, Xi-Min,Xu, Yan-Mei,Chen, Xin,Zhang, Hai-Bin,Hu, Long-Hua,Wang, Xiao-Zhong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Background: Chronic myeloid leukemia (CML) is a myeloproliferative disorder of hematopoietic stem cell scarrying the Philadelphia (Ph) chromosome and an oncogenic BCR-ABL1 fusion gene. The tyrosine kinase inhibitor (TKI) of BCR-ABL1 kinase is a treatment of choice for control of CML. Objective: Recent studies have demonstrated that miRNAs within exosomes from cancer cells play crucial roles in initiation and progression. This study was performed to assess miRNAs within exosomes of K562 cells. Methods: miRNA microarray analysis of K562 cells and K562 cell-derived exosomes was conducted with the 6th generation miRCURYTM LNA Array (v.16.0). Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were also carried out. GO terms and signaling pathways were categorized into 66 classes (including homophilic cell adhesion, negative regulation of apoptotic process, cell adhesion) and 26 signaling pathways (such as Wnt). Results: In exosomes, 49 miRNAs were up regulated as compared to K562 cells, and two of them were further confirmed by quantitative real-time PCR. There are differentially expressed miRNAs between K562 cell derived-exosomes and K562 cells. Conclusion: Selectively expressed miRNAs in exosomes may promote the development of CML via effects on interactions (e.g. adhesion) of CML cells with their microenvironment.

A Novel Zinc(II) Supramolecular Complex with Open 2D Channels

Feng-Qin Wang,Xiang-Jun Zheng,Yu-Xi Sun 대한화학회 2009 Bulletin of the Korean Chemical Society Vol.30 No.1

Protein Expression Analysis of Halobacillus dabanensis $D-8^T$ Subjected to Salt Shock

Feng De Qin,Zhang Bo,Lu Wei Dong,Yang Su Sheng The Microbiological Society of Korea 2006 The journal of microbiology Vol.44 No.4

To investigate the mechanism of salt tolerance of gram-positive moderately halophilic bacteria, two-dimensional gel electrophoresis (2-D PAGE) was employed to achieve high resolution maps of proteins of Halobacillus dabanensis $D-8^T$. Approximately 700 spots of proteins were identified from these 2-D PAGE maps. The majority of these proteins had molecular weights between 17.5 and 66 kDa, and most of them were distributed between the isoelectric points (pI) 4.0 and 5.9. Some protein spots were distributed in the more acidic region of the 2-D gel (pI <4.0). This pattern indicated that a number of proteins in the strain $D-8^T$ are acidic. To understand the adaptation mechanisms of moderately halophilic bacteria in response to sudden environmental changes, differential protein profiles of this strain were investigated by 2-D PAGE and $Imagemaster^{TM}$ 2D Platinum software after the cells were subjected to salt shock of 1 to 25% salinity for 5 and 50 min. Analysis showed 59 proteins with an altered level of expression as the result of the exposure to salt shock. Eighteen proteins had increased expression, S proteins were induced, and the expression of 33 proteins was down-regulated. Eight of the up-regulated proteins were identified using MALDI-TOF/MS and MASCOT, and were similar to proteins involved in signal transduction, proteins participating in energy metabolism pathways and proteins involved in stress.

Influence of Preparation Conditions on the Formation of Copper (II) Architectures with Pyrazine-2,3,5-tricarboxylic Acid

Feng-Qin Wang,Shu Lin,Ming-Lin Guo,Jun-Jian Xu,Xiao-Qing Wang,Yong-Nan Zhao 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.7

Three new metal-organic copper(II) complexes, [Cu(H_2PZTC)_2]_n·2nH_2O (1), [Cu(HPZTC)·2H_2O]_n·2nH_2O (2),and Cu_2[(PZHD)(OH)(H_2O)_2]_n (3) (H_3PZTC = pyrazine-2,3,5-tricarboxylic acid, PZHD^3− = 2-hydroxypyrazine-3,5-dicarboxylate), have been synthesized from Cu(II)/H3PZTC system under different synthetic conditions, and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectroscopy and thermogravimetric analysis. In complexes 1 and 2, H_3PZTC ligands loose one and two protons, which were transformed into H_2PZTC− anion and HPZTC^2− dianion under different preparation condition, respectively. Furthermore, two ligands coordinate with Cu(II) cations in different modes, leading to the formation of the different chain structures. In complex 3, H_3PZTC ligand was converted into a new ligand-PZHD by in situ decarboxylation and hydroxylation under a higher pH value than that for complexes 1 and 2. PZHD ligands link the Cu(II) cations to form a 2D layer structure. These results demonstrate that the preparation conditions,including pH value and reaction temperature etc, play an important role in the construction of complexes based on H_3PZTC ligand.

Anatomic Variants on Computed Tomography in Congenital Aural Atresia and Stenosis

Feng-hua Qin,Tian-yu Zhang,Peidong Dai,Lin Yang 대한이비인후과학회 2015 Clinical and Experimental Otorhinolaryngology Vol.8 No.4

Objectives. To quantitatively analyzing the anatomic variants on temporal computed tomography (CT) in congenital external auditory canal stenosis (EACS), congenital aural atresia (CAA), and normal ear structure. Methods. Through a retrospective study, we analyzed 142 temporal high-resolution CT studies performed in 71 microtia patients. The following 6 parameters were compared among the three groups: Marx classification, medial canal diameter, vertical facial nerve (VFN) anterior displacement, tegmen mastoideum position, tympanic cavity volume, and malleus-incus joint or malleus-incus complex (MIC) area. Results. The results showed that the microtia distributions in the Marx classification in these three groups were significantly different, as 86% (31 of 35) of ears with major microtia (third-degree dysplasia) had an atresia, and in 54.8% (23 of 42) of the minor microtic (first-degree or second-degree) ears, the bony or cartilaginous part of the external auditory canal was stenotic. Measurement data also showed that the potential medial canal diameter of the atresia group was obviously shorter than that of the stenosis group. The VFN anterior displacement and temporomandibular joint backward-shift together lead to medial canal diameters in ears with atresic canals that is smaller than those with stenotic canals. The tegmen mastoideum position was not significantly different between the three groups. Conclusion. The mal-development of the external auditory canal is significantly associated with auricle and middle ear developmental anomalies. Compared with CAA ears, EACS have better development of the auricle, canal, tympanic cavity and MIC and relatively safer surgical operation except for the position of the tegmen mastoideum and the VFN.

Regional innovation networks and risk analysis based on Industry-University-Reserach Institution

Feng Feng,Xue Qin 인하대학교 정석물류통상연구원 2009 인하대학교 정석물류통상연구원 학술대회 Vol.2009 No.10

According to the system theory, the structure of the network determines characteristics of the network. Our paper builds a regional innovation network of Industry-University-Research Institution and analyzes the network structure variables the aggregation coefficient, average shortest path length, degree distribution by social network model. The result is obtaining the contact between network structure variables and risks, which will improve and promote the formation and development of the regional innovation networks based on Industry-University-Research Institution.

Serum CEA Level Change and Its Significance Before and after Gefitinib Therapy on Patients with Advanced Non-small Cell Lung Cancer

Qin, Hai-Feng,Qu, Li-Li,Liu, Hui,Wang, Sha-Sha,Gao, Hong-Jun Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.7

Objective: The aim of this study was to explore change and significance of serum carcino-embryonic antigen (CEA) before and after gefitinib therapy in patients with advanced non-small-cell lung cancer (NSCLC). Methods: Forty patients with advanced NSCLCs in III~IV stages were selected as study objects given gefitinib therapy combined with routine local radiotherapy until tumor progression or intolerable toxicity. After treatment, all patients were divided into control and non-control groups according to the results of evaluation based on RECIST 1.1 (Response Evaluation Criteria in Solid Tumors in 2009). Peripheral fasting blood from all patients was collected in the early morning and serum CEA was assessed by electro-chemiluminescence immunoassay (ECLIA) before and after treatment. Before treatment, patients were divided into high CEA group (CEA level > 50 ng/mL) and low CEA group (CEA level ${\leq}$ 50 ng/mL). Adverse reactions were noted and progression-free survival (PFS) in both groups was recorded after long-term follow-up that ended in December, 2012. Results: There was no difference between control and non-control groups in CEA level before treatment (P>0.05), whereas serum CEA decreased more markedly lower in the control group after treatment (P<0.01). All patients were divided into high CEA group (26) and low CEA group (14) according to serum CEA level. There was no statistically significant difference between two groups in adverse reactions (P>0.05) but the rate in former group was lower. Additionally, survival rates at 9 and 12 months in high CEA group were clearly higher than in the low CEA group (P<0.01). Conclusions: Serum CEA level can serve as a biochemical index to evaluate the prognosis with gefitinib treatment for NSCLC.