Comparative study of the microstructure of Ti-6Al-4V titanium alloy sheets under quasi-static and high-velocity bulging

Fen-Qiang Li,Jun Zhao,Jian-Hua Mo,Jian-Jun Li,Liang Huang 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.3

In order to reveal the high-velocity deformation mechanisms of Ti-6Al-4V titanium alloy sheets, the dynamic deformation behavior and the microstructure evolutions were compared with those under quasi-static case employing Scanning electron microscopy/Electron back-scattered diffraction (SEM/EBSD) and Transmission electron microscopy (TEM). The results indicated that the distribution of microhardness was uneven. The cause was determined to be the non-uniform material flow and dynamic loading. The grain sizes of the Ti-6Al-4V titanium alloy sheet were nearly the same under two conditions, but the grains were elongated under the dynamic loading compared with that observed in quasi-static forming. In high-velocity bulging, dislocation slip was the principle mechanism of plastic deformation of Ti-6Al-4V titanium alloy when deformation was small. As the strain increased, the twinning phenomenon was activated in addition to the dislocation cell structure. The twinning plane was determined to be the (10 11) plane.

Optimizing the binding activity of the AP2/ERF transcription factor with the GCC box element from Brassica napus by directed evolution

( Xiao Fen Jin ),( Bo Zhu ),( Ri He Peng ),( Hai Hua Jiang ),( Jian Min Chen ),( Jing Zhuang ),( Jian Zhang ),( Quan Hong Yao ),( Ai Sheng Xiong ) 생화학분자생물학회 (구 한국생화학분자생물학회) 2010 BMB Reports Vol.43 No.8

In this study, we cloned the ERF-B3 subfamily transcription factor gene BnaERF-B3-hy15 from Brassica napus L. Huyou15. This 600 bp gene encodes a 199 amino acid classic ethylene responsive factor (ERF), which shown no binding or very weak binding GCC box-binding activity by the yeast one-hybrid assay. We used gene shuffling and the yeast one-hybrid system to obtain three mutated sequences that can bind to the GCC box. Sequence analysis indicated that two residues, Gly156 in the AP2 domain and Phe62 at the N-terminal domain were mutated to arginine and serine, respectively. Changes of Gly156 to arginine and Phe62 to serine increased the GCC- binding activity of BnaERF-B3-hy15 and the alter of Gly156 to arginine changed the AP2-domain structure of BnaERF-B3- hy15. [BMB reports 2010; 43(8): 567-572]

아드만탄 기반의 새로운 설포네이트 폴리카보네이트 난연제 성능 연구

Jian Wei Guo,Yue Qin Wang,Li Juan Feng,Xing Zhong,Chu Fen Yang,Sa Liu,Ying De Cui 한국고분자학회 2013 폴리머 Vol.37 No.4

A novel sulfonate flame retardant, 1,3,5,7-tetrakis(phenyl-4-sodium sulfonate)adamantane (FR-A), was suc-cessfully synthesized from l-bromoadamantane in sequential four-step reactions involving Fiedel-Crafts phenylation, sul-phonation, hydrolysis, and neutralization. The success of synthesis was confirmed by FTIR spectra, ‘H NMR spectra, elemental analyses and mass spectra. The effect of FR-A on the flame retardacy of polycarbonate (PC) has been studied. Limiting oxygen index (LOI) and thermogravimetric analysis (TGA) showed that this novel sulfonate flame retardant had effective flame retardancy on polycarbonate (PC). With a small amount (0.08 Wt%) of FR-A. the flame retardancy of PC was improved obviously, which got to UL 94 V-0 rating. TGA and DTA curves demonstrated that the additive raised the degradation rate of PC by promoting the quick formation of an insulating carbon layer on the surface, and confirmed that the flame retardant mechanism of PC/FR-A system was similar to potassium diphenylsulfone sulfonate (KSS).

CTNNB1 Mutation in Aldosterone Producing Adenoma

Jian-Jhong Wang,Kang-Yung Peng,Vin-Cent Wu,Fen-Yu Tseng,Kwan-Dun Wu 대한내분비학회 2017 Endocrinology and metabolism Vol.32 No.3

Discoveries of somatic mutations permit the recognition of subtypes of aldosterone-producing adenomas (APAs) with distinct clinical presentations and pathological features. Catenin β1 (CTNNB1) mutation in APAs has been recently described and discussed in the literature. However, significant knowledge gaps still remain regarding the prevalence, clinical characteristics, pathophysiology, and outcomes in APA patients harboring CTNNB1 mutations. Aberrant activation of the Wnt/β-catenin signaling pathway will further modulate tumorigenesis. We also discuss the recent knowledge of CTNNB1 mutation in adrenal adenomas.

Analysis of Volatile Compounds of Jasmine Scented Tea during the Orthodox Manufacturing Process Using HS-SPME/GC-MS

Jian Lu,De-Jun Fu,Dong-Fen Wu,Yu Liu,Yao-Ping Luo 한국차학회 2015 한국차학회지 Vol.- No.S

Volatile components of jasmine-scented tea during the orthodox manufacturing process were extracted using Headspace solid-phase microextraction (HS-SPME) and the major flavor compounds were identified by Gas chromatography-mass spectrometry/Retention indices (GC-MS/RI). The major volatile compounds extracted by SDE could also be obtained by HS-SPME, which appears more suitable for extraction of aromatic compounds, for its advantages of simplicity and convenience. The GC-MS chromatograms of tea samples showed that the aromatic constituents of jasmine tea had been identified in composition after 1st scenting, which contained 6 apparently high peaks representing linalool, benzyl acetate, α-farnesene, (Z)-3-hexenyl benzoate, methyl anthranilate, and indole. According to the change of peak area of major volatile compounds, (Z)-3-hexenyl acetate and (Z)-3-hexenyl butyrate with green grass aroma reduced by 71.13% and 63.10% respectively in jasmine tea product, while 7 compounds with favorable flowery fruity aroma-benzyl acetate, (Z)-3-hexenyl benzoate, linalool, benzyl alcohol, α-farnesene, methyl anthranilate and indole- increased by 17.84%, 28.33 times, 32.49%, 1.70 times, 6.67 times, 11.84 times and 21.48 times respectively, comparing to the base tea. Besides, nerolidol (fruity-flowery) and germacrene D (woody), not detected in the base tea also gradually increased. The quality grade of jasmine tea was potentially correlated to the ratio of peak area of the 9 favorable compounds to that of the 2 grass compounds. After 1st scenting, the peak areas of compounds from jasmine flower increased by 1.81×105-18.24×105, and decreased by 36.14%-69.95% after the 1st drying. The peak areas of some components detected in both the base tea and jasmine flowers, like (Z)-3-hexenyl acetate and methyl salicylate, increased by 9.05%-57.60% of those of the base tea after 1st scenting, and lost more than 100% after the 1st drying, while the increased peak areas of some other components both detected, like α-farnesene and indole, were more than peak areas of the base tea, with 30%- 95% loss after the 1st drying. The content change tendency of volatiles during 2nd scenting and the 2nd drying were consistent with those during 1st scenting and the 1st drying. After raising fragrance, the contents of some low boiling point volatiles and compounds not detected in the base tea increased.

VRML Database Access for 3D Real-time Data Visualization in MiWi<SUP>TM</SUP> Thermal Wireless Sensor Network

Xue-fen Wan(만설분),Yi Yang(양의),Jian Cui(최검),Tao Zheng(정도),Li Ma(마려) 대한전자공학회 2012 전자공학회논문지 Vol.49 No.12

본 논문에서는 중국 현지 염색 기업의 열 센서망에 적용 가능한 원격 가상 현실 제어 플랫폼에서 실행할 수 있는 데이터베이스 액세스를 가상 현실 모델링 언어 (VRML)를 소개하였다. 또한, 3차원 실시간 자료 시각화를 위한 가상 현실 모델링 언어-액티브엑스 서버 페이지(VRML-ASP)를 소개하였다. 나아가 이와 관련된 스크립트도 다루었을 뿐만 아니라, 열 센서 노드와 센서 영역에서의 움직임을 분석하였다. 이 데이터베이스 프레임워크는 마이크로칩에서 발표한 마이와이<SUP>TM</SUP>(MiWi<SUP>TM</SUP>)의 표준에 최적화되었다. 이러한 분석 결과를 근거로, 시스템 구성에 따라 가상 현실 모델링 언어-액티브엑스 서버 페이지(VRML-ASP) 데이터 액세스 프레임워크가 가상 현실 원격 산업 공정 제어 시스템을 위한 하나의 경쟁력 있는 데이터 관리 해결책이 될 수 있음을 확인할 수 있었다. A Virtual Reality Modeling Language (VRML) database access in remote virtual reality control platform for dyeing enterprise MiWi<SUP>TM</SUP> thermal sensor network is presented in this paper. The VRML-ASP framework is introduced for 3D real-time data plotting in this application. The activities of thermal sensor nodes and sensor area are analyzed. The database access framework is optimized for MiWi<SUP>TM</SUP> wireless sensor networks. The experimental results show that VRML-ASP database access framework could be a reliable and competitive data-manage candidate for targeted virtual reality remote industrial visualization application.

OsAREB1, an ABRE-binding protein responding to ABA and glucose, has multiple functions in Arabidopsis

( Xiao Fen Jin ),( Ai Sheng Xiong ),( Ri He Peng ),( Jin Ge Liu ),( Feng Gao ),( Jian Min Chen ),( Quan Hong Yao ) 생화학분자생물학회 2010 BMB Reports Vol.43 No.1

Extracellular loop 3 (EL3) and EL3-proximal transmembrane helix 7 of the mammalian type I and type II gonadotropin-releasing hormone (GnRH) receptors determine differential ligand selectivity to GnRH-I and GnRH-II.

Li, Jian Hua,Choe, Han,Wang, Ai Fen,Maiti, Kaushik,Wang, Chengbing,Salam, Abdus,Chun, Sang Young,Lee, Won-Kyo,Kim, Kyungjin,Kwon, Hyuk Bang,Seong, Jae Young American Society for Pharmacology and Experimental 2005 Molecular pharmacology Vol.67 No.4

<P>Mammalian type I and II gonadotropin-releasing hormone (GnRH) receptors (GnRHRs) show differential ligand preference for GnRH-I and GnRH-II, respectively. Using a variety of chimeric receptors based on green monkey GnRHR-2 (gmGnRHR-2), a representative type II GnRHR, and rat GnRHR, a representative type I GnRHR, this study elucidated specific domains responsible for this ligand selectivity. A chimeric gmGnRHR-2 with the extracellular loop 3 (EL3) and EL3-proximal transmembrane helix 7 (TMH7) of rat GnRHR showed a great increase in ligand sensitivity to GnRH-I but not to GnRH-II. Point-mutation studies indicate that four amino acids, Leu/Phe(7.38), Leu/Phe(7.43), Ala/Pro(7.46), and Pro/Cys(7.47) in TMH7 are critical for ligand selectivity as well as receptor conformation. Furthermore, a combinatory mutation (Pro(7.31)-Pro(7.32)-Ser(7.33) motif to Ser-Glu-Pro in EL3 and Leu(7.38), Leu(7.43), Ala(7.46), and Pro(7.47) to those of rat GnRHR) in gmGnRH-2 exhibited an approximately 500-fold increased sensitivity to GnRH-I, indicating that these residues are critical for discriminating GnRH-II from GnRH-I. [Trp(7)]GnRH-I and [Trp(8)]GnRH-I but not [His(5)]GnRH-I exhibit a higher potency in activating wild-type gmGnRHR-2 than native GnRH-I, indicating that amino acids at positions 7 and 8 of GnRHs are more important than position 5 for differential recognition by type I and type II GnRHRs. As a whole, these data suggest a molecular coevolution of ligands and their receptors and facilitate the understanding of the molecular interaction between GnRHs and their cognate receptors.</P>

Medical Image Registration Based on Inertia Matrix and Iterative Closest Point

Mei-sen Pan,Jian-jun Jiang,Qiu-sheng Rong,Fen Zhang 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.8

The closest iterative point algorithm (ICP) is widely used in medical image registration. But there exist some problems in the following aspects. First, due to its heavily computational load, it has a time-consuming process and a low registration efficiency. Second, due to the fact that it heavily depends on whether the initial rotation and translation matrices of the floating point set can be exactly extracted, it often traps in the local optimum and even fails to register images. In addition, due to the complexity of medical images, it is difficult to automatically extract the salutary feature points. In this paper, by computing the coordinate inertia matrices of the reference and floating images, the rotation angles are obtained and referred to as the initial rotation parameters of ICP for image registration. The edges of the reference and floating images are detected by the edge convolution kernel so-called B-spline gradient operator (BSGO) and then the binarization images involving the feature points are acquired. The experimental results reveal that, this proposed method has a fairly simple implementation, a low computational load, a fast registration and good alignment accuracy. Also, It can efficiently avoid trapping in the local optimum and cater to both mono-modality and multi-modality image registrations.

A Novel Hysteresis Control Strategy Based on Ampere-Second Balance of the Modulate Capacitor

Jin-Bin Zhao,Jian-Feng Dai,Ke-Qing Qu,Fen Li 전력전자학회 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.6

A novel hysteresis PWM control strategy for synchronous buck converter is proposed. The proposed control strategy is based on ampere-second balance of the modulate capacitor, which not only offers faster transient response to meet the challenges of the power supply requirements of fast dynamic load changes, but also provides better stability and solves the compensation problem of error amplifier in the conversional voltage PWM control. Finally, the steady-state and dynamic operation of the control method is analyzed and verified by simulation and experimental results.