Structural and nanomechanical properties of a-plane ZnO thin films deposited under different oxygen partial pressures

Sheng-Rui Jian,Hou-Guang Chen,Guo-Ju Chen,Jason S.C. Jang,Jenh-Yih Juang 한국물리학회 2012 Current Applied Physics Vol.12 No.3

The effects of O2 partial pressure during RF magnetron sputtering on the structural and nanomechanical properties of a-plane ZnO thin films were investigated by using X-ray diffraction (XRD) and nanoindentation techniques. The XRD and the transmission electron microscopy (TEM) selected area diffraction results indicate that the epitaxial relationship between ZnO thin films and Al2O3 substrates is ZnO ð1120Þ//Al2O3 ð1102Þ. The average values of the hardness and Young’s modulus of the a-plane ZnO films were found to decrease with increasing oxygen partial pressure. The cross-sectional TEM revealing the localized plastic deformation of ZnO thin films beneath the Berkovich indenter, indicating the prominent role played by the threading dislocations in the film deformation behavior. At higher indentation loadings, the sapphire substrate exhibits extensive deformation with narrow slip bands appearing on {0001} plane. However, no evidence of pressure-induced phase transformation, as well as cracking and/or delamination phenomena at the filmesubstrate interface was observed.

Molecular characterization and functional analysis of a protease-related protein in Chang-Liver cells

( Cong Rui Wang ),( Hui Yong Zhang ),( Hui Gen Feng ),( Bao Sheng Yang ),( Jogenananda Pramanik ),( Zhi Kun Guo ),( Jun Tang Lin ) 생화학분자생물학회 (구 한국생화학분자생물학회) 2010 BMB Reports Vol.43 No.5

In this study, the cDNA library of Chang-liver cells was immunoscreened using common ADAMs antibody to obtain ADAM related genes. We found one positive clone that was confirmed as a new gene by Blast, which is an uncharacterized helical and coil protein and processes protease activity, and named protease-related protein 1 (ARP1). The submitted GenBank accession number is AY078070. Molecular characterizations of ARP1 were analyzed with appropriate bioinformatics software. To analyse its expression and function, ARP1 was subcloned into glutathione S-transferase fusion plasmid pGEX-2T and expressed by E. coli system. The in vitro expression product of ARP1 was recognized by common ADAMs antibody with western blot. Interestingly, ARP1 cleaves gelatine at pH9.5, which suggests it is an alkaline protease. Semi-quantitative RT-PCR result indicates that ARP1 mRNA is strongly transcribed in the liver and the treated Chang-liver cells. [BMB reports 2010; 43(5): 375-381]

Collision avoidance and orientation planning for ball-end cutter

Xiangyu Guo,Rui Wang,Shi-Sheng Zhong 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.8

Propeller blades have freeform surfaces, and the overlap among the blades limits the adjustment range of cutter orientation, making it extremely difficult to generate the required cutter orientation. Therefore, to assist in quickly designing a safe and reasonable machining scheme, a projection-offset method is designed to calculate the feasible region of a ballend cutter and an XYZ-3RPS hybrid kinematic mechanism. Based on this, a reasonable and smooth cutter orientation can be generated using path-planning and trajectory-optimization algorithms. To this end, a method for obtaining point clouds was first developed. By arranging the point clouds of a blank in the cutter path order, the changes to the blank during the machining process can be reflected through point-cloud deletion. A hierarchical bounding box is established for the moving platform of the cutter, spindle, and mechanism, which can realize the quick screening and classification of collision-point clouds. Second, the collision points are projected onto the same plane, an envelope boundary of the projected point cloud was constructed using an alpha-shapes algorithm, and its cross boundary trimmed using the auxiliary boundary method to obtain the feasible region at the cutter contact point. Moreover, to reduce the computational load, an interpolation method, which reduces the number of calculations, is used. The basic rules for cutter-orientation generation were established using a planning function. Then, the cutter-orientation path was smoothed using the trajectory-optimization algorithm to prevent the cutter from swinging violently. Finally, the effectiveness of this method was verified through propeller experiments.

Double-sided collaborative machining for propeller blade based on XYZ-3RPS hybrid kinematic machine

Xiangyu Guo,Rui Wang,Shi-Sheng Zhong 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.10

At present, propeller blades are machined single-sided with low efficiency. Thus, a propeller needs to be turned over after completion of the machining of the first side of the blade, which requires second clamping and causes a decline in accuracy. Therefore, a doublesided collaborative machining method for propeller blades is proposed herein. Two XYZ-3RPS hybrid kinematics machines were symmetrically distributed to machine both sides of a propeller blade simultaneously; therefore, the blade could be machined in clamping once, improving the machining efficiency and eliminating the accuracy decline caused by repetitive clamping. Moreover, a supporting device with rigid-flexible switching capability was developed to reduce the cantilever length of the blade, thereby eliminating the substantial deformation and vibration of the blade during the double-sided collaborative machining process to ensure machining accuracy. Additionally, the inverse kinematics formula for XYZ-3RPS hybrid kinematics machines was deduced and the elongation of each drive shaft through the cutter location point and cutter orientation was solved in this study. Thereafter, the decomposition method of the blade shift data was applied to obtain the deformation and vibration amplitude of the blade so that the performance of the double-sided cooperative machining could be quantitatively analyzed. Finally, experiments were conducted on the self-developed prototype, and the results verified the effectiveness of the double-sided collaborative machining method in reducing the deformation and vibration of a blade and improving machining efficiency.

Transgenic Rice Overexperessing a Tomato Mitochondrial Phosphate Transporter, SlMPT3;1, Promotes Phosphate Uptake and Increases Grain Yield

Xian-guo Cheng,Guo-hong Yu,Sheng-cai Huang,Rui He,Ying-Zhang Li 한국식물학회 2018 Journal of Plant Biology Vol.61 No.6

Mitochondrial phosphate transporter plays animportant regulatory role in promoting the uptake andtransport of phosphate in plants. In this study, the SlMPT3;1gene, a member of mitochondrial phosphate transporterfamily in tomato, was isolated and transformed into the riceOryza sativa L. ssp. japonica cultivar Kitaake. The SlMPT3;1 islocalized to the mitochondrial membrane and functions incompensating the phosphate uptake in yeast MB192 mutantthat is defective in phosphate transport under Pi deficiency. RT-qPCR showed that the SlMPT3;1 is expressed in all oftomato tissues, but highly accumulated in the young leavesand stems under Pi deficiency. The data demonstrated that atleast two copies of the SlMPT3;1 gene are inserted into therice genome, and the transcripts of the SlMPT3;1 mRNA arehighly accumulated in the roots of the transgenic rice. Theoverexpression of the SlMPT3;1 gene not only promotesphosphate uptake by the roots, but also increases thetranslocation of phosphate from the roots to the shoots in thetransgenic rice. The transgenic rice accumulated morechlorophyll and soluble sugar in the shoots than the wildtype under Pi deficiency. Microassay sequencing showedthat the differentially expressed genes in the transgenic riceare mainly involved in the regulations of biological processand molecular function under Pi deficiency. Further RTqPCRanalyses revealed that the differentially expressedgenes, which are involved in the regulations of the biologicalprocess, cell component, and molecular function, are upregulatedunder Pi deficiency, and exhibit similar expressiontrends to the relative expression folds of these partial differentiallyexpressed genes in the transcriptomic analyses. This studysuggests that the overexpression of the SlMPT3;1 gene promotedthe uptake and transport of phosphate in rice, thus leading to anenhanced increase in tiller number and effective panicle of perplant, and increasing grain yield under Pi deficiency.

Field Emission from TiO2/Ti Nanotube Array Films Modified with Carbon Nanotubes

Cheng-Wei Wang,Rui-Sheng Guo,Jian-Biao Chen,Yan Li,Jian Wang,Wei-Min Liu 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.6

Well-aligned TiO2/Ti nanotube array films were synthesized by using anodic oxidation of titanium in 0.5-wt% HF and were modified with carbon nanotubes (CNTs) assembled by using catalyzed chemical vapor deposition (CVD) at 650 ˚C. The morphology and the quality of the films were assessed with field emission scanning electron microscopy and Raman spectrometry (325 nm). The field emission characteristics of such TiO2/Ti nanostructures were investigated before and after being modified with CNTs. The results show that the TiO2/Ti nanotube arrays possess a moderate turn-on electric field of 7.4 V/µm, a field emission current density of 2.7 mA/cm2 at 23 V/µm. It is noteworthy that the turn-on field of the TiO2/Ti nanotube arrays modified with CNTs is decreased significantly to 1.3 V/µm, and the emission current density is increased to 10 mA/cm2 at 5.6 V/µm. This novel structure shows high emission efficiency as a field emitter. Well-aligned TiO2/Ti nanotube array films were synthesized by using anodic oxidation of titanium in 0.5-wt% HF and were modified with carbon nanotubes (CNTs) assembled by using catalyzed chemical vapor deposition (CVD) at 650 ˚C. The morphology and the quality of the films were assessed with field emission scanning electron microscopy and Raman spectrometry (325 nm). The field emission characteristics of such TiO2/Ti nanostructures were investigated before and after being modified with CNTs. The results show that the TiO2/Ti nanotube arrays possess a moderate turn-on electric field of 7.4 V/µm, a field emission current density of 2.7 mA/cm2 at 23 V/µm. It is noteworthy that the turn-on field of the TiO2/Ti nanotube arrays modified with CNTs is decreased significantly to 1.3 V/µm, and the emission current density is increased to 10 mA/cm2 at 5.6 V/µm. This novel structure shows high emission efficiency as a field emitter.

An assumed mode method and finite element method investigation of the coupled vibration in a flexible-disk rotor system with lacing wires

Shui-Ting Zhou,YiJui Chiu,Guo-Fei Yu,Chia-Hao Yang,Hong-Wu Huang,Sheng-Rui Jian 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.2

The Assumed mode method (AMM) and Finite element method (FEM) were used. Their results were compared to investigate the coupled shaft-torsion, disk-transverse, and blade-bending vibrations in a flexible-disk rotor system. The blades were grouped with a spring. The flexible-disk rotor system was divided into three modes of coupled vibrations: Shaft-disk-blade, disk-blade, and blade-blade. Two new modes of coupled vibrations were introduced, namely, lacing wires-blade and lacing wires-disk-blade. The patterns of change of the natural frequencies and mode shapes of the system were discussed. The results showed the following: first, mode shapes and natural frequencies varied, and the results of the AMM and FEM differed; second, numerical calculation results showed three influencing factors on natural frequencies, namely, the lacing wire constant, the lacing wire location, and the flexible disk; lastly, the flexible disk could affect the stability of the system as reflected in the effect of the rotational speed.

Probabilistic Object Recognition in a Sequence of 3D Images

장대식(Jang Dae Sik),이양원(Yang Won Rhee),성국서(Guo Rui Sheng) 한국컴퓨터정보학회 2006 한국컴퓨터정보학회지 Vol.14 No.1

냉장고나 에어컨 등과 같은 비교적 크고 자주 움직이지 않는 물체들에 대한 인식은 실내 환경에서의 SLAM(Simultaneous Localization and Map building) 문제에서 중요한 전역적 고정 특징으로 사용될 수 있다는 측면에서 그 필요성이 크다. 본 논문에서는 연속적으로 획득되는 3차원의 영상 장면들을 사용하여 이러한 큰 물체들을 안정적으로 인식할 수 있는 방법을 제안한다. 제안하는 방법에서는 파티클 필터(Particle Filter)를 기반으로 연속적인 3차원 영상에서 점진적으로 3차원의 물체를 인식하는 방법을 사용한다. 이를 위해 인식하고자 하는 하나의 물체를 표현하는 파티클(Particle) 들을 3차원의 장면에 뿌리고, 3차원 선들의 정합을 통해 각 파티클에 대한 정합 확률을 계산한다. 이 확률과 정합된 파티클의 비율을 기반으로 3차원 환경 속에 놓여진 물체를 인식할 수 있으면 물체의 자세 또한 함께 인식될 수 있다. 실험 결과를 통해 파티클 필터에 기반한 점진적이고 확률적인 물체인식의 가능성을 보이고 SLAM 문제에 응용한 결과도 함께 보여준다. The recognition of a relatively big and rarely movable object, such as refrigerator and air conditioner, etc. is necessary because these objects can be crucial global stable features of Simultaneous Localization and Map building(SLAM) in the indoor environment. In this paper, we propose a novel method to recognize these big objects using a sequence of 3D scenes. The particles representing an object to be recognized are scattered to the environment and then the probability of each particles is calculated by the matching test with 3D lines of the environment. Based on the probability and degree of convergence of particles, we can recognize the object in the environment and the pose of object is also estimated. The experimental results show the feasibility of incremental object recognition based on particle filtering and the application to SLAM.

ZNF488 Enhances the Invasion and Tumorigenesis in Nasopharyngeal Carcinoma Via the Wnt Signaling Pathway Involving Epithelial Mesenchymal Transition

Dan Zong,Li Yin,Qian Zhong,Wen-jie Guo,Jian-hua Xu,Ning Jiang,Zhi-rui Lin,Man-zhi Li,Ping Han,Lin Xu,Xia He,Mu-sheng Zeng 대한암학회 2016 Cancer Research and Treatment Vol.48 No.1

Purpose The purpose of this study was to investigate the function of Zinc finger protein 488 (ZNF488) in nasopharyngeal carcinoma (NPC). Materials and Methods The endogenous expression of ZNF488 in NPC tissues, normal nasopharyngeal epithelium tissues and NPC cell lines were detected by quantitative reverse transcription polymerase chain reaction. ZNF488 over-expressing and knock-down NPC cell line models were estab- lished through retroviral vector pMSCV mediated over-expression and small interfering RNA (siRNA) mediated knock-down. The invasion and migration capacities were evaluated by wound healing and transwell invasion assays in ZNF488 over-expressing and control cell lines. Soft-agar colony formation and a xenograft experiment were performed to study tumorigenic ability in vitro and in vivo. Immunofluorescence and western blotting analysis were used to examine protein changes followed by ZNF488 over-expression. Microarray analysis was performed to explore gene expression profilings, while luciferase reporter assay to evaluate the transcriptive activity of Tcf/Lef. Results ZNF488 was over-expressed in NPC tissues compared with normal tissues, especially higher in 5-8F and S18, which are well-established high metastatic NPC clones. Functional studies indicate that over-expression of ZNF488 provokes invasion, whereas knock-down of ZNF488 alleviates invasive capability. Moreover, over-expression of ZNF488 promotes NPC tumor growth both in vitro and in vivo. Our data further show that over-expression of ZNF488 induces epithelial mesenchymal transition (EMT) by activating the WNT/β -catenin signaling pathway. Conclusion Our data strongly suggest that ZNF488 acts as an oncogene, promoting invasion and tumorigenesis by activating the Wnt/β -catenin pathway to induce EMT in NPC.