An intelligent method to design die profile for rubber forming of complex curved flange part

Ling‑Yun Zhang,Shuai Zhou,Tian‑Zhang Zhao,Yi‑Pan Zeng 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.1

Rubber forming is an important forming process for the manufacture of aircraft sheet metal parts. The springback is one of the main defects in rubber forming. Classical springback compensation by displacement adjustment method using finite simulation is not satisfactory. In this research, the algorithms of compensating the arc and flange surface of complex curved flange with correction formula are proposed by experiment. The correction formula was developed based on the CATIA V5 R19 using Component Application Architecture. Compensate profile is presented including surface pick up, line pick up, division, compensation, extending, and trimming. The die profile of part with complex curved flanges in aircraft could be designed rapidly. It was found that the forming pressure has a little effect on the springback. This is within the tolerance limits of the part. The results reveal the method can achieve the industrial part precisely. The method is demonstrated on an aircraft wing rib part.

Characterization and Antioxidant Activity of the Exopolysaccharide Produced by Bacillus amyloliquefaciens GSBa-1

( Wen Zhao ),( Jian Zhang ),( Yun-yun Jiang ),( Xiao Zhao ),( Xiao-na Hao ),( Liu Li ),( Zhen-nai Yang ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.8

The exopolysaccharide (EPS) produced by Bacillus amyloliquefaciens GSBa-1 was isolated and purified by ethanol precipitation, and DEAE-cellulose and Sepharose CL-6B chromatographies. The molecular mass of the purified EPS was determined to be 54 kDa. Monosaccharide analysis showed that the EPS was composed of predominantly glucose, and it was further confirmed by NMR spectroscopy to be α-glucan that consisted of a trisaccharide repeating unit with possible presence of two α-(1→3) and one α-(1→6) glucosidic linkages. Microstructural analysis showed that the EPS appeared as ellipsoid or globose with a smooth surface. The EPS had a degradation temperature at 240℃. Furthermore, the EPS had strong DPPH and hydroxyl radical scavenging activities, and moderate superoxidant anion scavenging and metal ion-chelating activities. This is the first characterization of a glucan produced by B. amyloliquefaciens with strong antioxidant activity. The results of this study suggest the potential of the EPS from B. amyloliquefaciens GSBa-1 to serve as a natural antioxidant for application in functional products.

A brain somatic RHEB doublet mutation causes focal cortical dysplasia type II

Shanshan Zhao,Zhenghui Li,Muxian Zhang,Lingliang Zhang,Honghua Zheng,Jinhuan Ning,Yanyan Wang,Feng-Peng Wang,Xiaobin Zhang,Hexia Gan,Yuanqing Wang,Xian Zhang,Hong Luo,Guojun Bu,Huaxi Xu,Yi Yao,Yun-wu 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Focal cortical dysplasia type II (FCDII) is a cerebral cortex malformation characterized by local cortical structure disorganization, neuronal dysmorphology, and refractory epilepsy. Brain somatic mutations in several genes involved in the PI3K/AKT/mTOR pathway are associated with FCDII, but they are only found in a proportion of patients with FCDII. The genetic causes underlying the development FCDII in other patients remain unclear. Here, we carried out whole exome sequencing and targeted sequencing in paired brain–blood DNA from patients with FCDII and identified a brain somatic doublet mutation c.(A104T, C105A) in the Ras homolog, mTORC1 binding (RHEB) gene, which led to the RHEB p.Y35L mutation in one patient with FCDII. This RHEB mutation carrier had a dramatic increase of ribosomal protein S6 phosphorylation, indicating mTOR activation in the region of the brain lesion. The RHEB p.Y35L mutant protein had increased GTPλS-binding activity compared with wild-type RHEB. Overexpression of the RHEB p. Y35L variant in cultured cells also resulted in elevated S6 phosphorylation compared to wild-type RHEB. Importantly, in utero electroporation of the RHEB p.Y35L variant in mice induced S6 phosphorylation, cytomegalic neurons, dysregulated neuron migration, abnormal electroencephalogram, and seizures, all of which are found in patients with FCDII. Rapamycin treatment rescued abnormal electroencephalograms and alleviated seizures in these mice. These results demonstrate that brain somatic mutations in RHEB are also responsible for the pathogenesis of FCDII, indicating that aberrant activation of mTOR signaling is a primary driver and potential drug target for FCDII.

A Novel Capacitive Negative Electrode Material of Fe3N

Zhi-Yun Zhao,Wei-Bin Zhang,Xue-Jing Ma,Kai Li,Yue Zhao,Jian-Fei Gao,Long Kang,Ling-Bin Kong 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.1

A capacitive negative electrode material of Fe3N has been synthesized via a simple precursor ammoniation treatment. Electrochemical measure shows that the electrode exhibits a specific capacitance of 270 F · g -1 at a current density of 0.5A · g -1 in 6M KOH, 66% of the initial value remains at a specific current density of 5A · g -1. Capacitance retention after 5000 cycles is about 61.5% of the initial capacitance. The electrochemical performance is relatively great in comparison with the literature reports of some Fe-based compounds. Because of the low cost and simple preparation method of Fe3N, the material is promising in electrochemical capacitive energy storage applications.

ROOM-TEMPERATURE FERROMAGNETISM IN SnO 2 NANOFIBERS AND NANOTUBES PREPARED BY ELECTROSPINNING

JIAN-GUO ZHAO,WEI-YING ZHANG,ZHAO-JUN LIU,ZHONG-LI LIU,YA-JUAN ZHANG,ER-QING XIE,XIU-YUN AN,YONG-FENG CHEN,CHANG-YOU ZHANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.2

SnO 2 nano¯bers and nanotubes were synthesized by electrospinning method. Magnetizationmeasurement indicates that the SnO 2 nano¯bers and nanotubes annealed in air at 500?C exhibitthe room-temperature ferromagnetism and the ferromagnetism of nanotubes is stronger than thenano¯bers. Selected area electron di®raction, X-ray di®raction and Raman measurements showthat all the samples possess a typical rutile structure and no other impurity phases are observed. The results of the Raman spectra also indicate that there are lots of defects existing in thefabricated samples. The observed room-temperature ferromagnetism in SnO 2 nano¯bers andnanotubes possibly originates from oxygen vacancies. The ¯eld cooled (FC) and zero-¯eld-cooled(ZFC) magnetization curves indicate that the Curie temperature T C is above 300 K.

Effectiveness and Safety of Dabrafenib in the Treatment of 20 Chinese Children with BRAFV600E-Mutated Langerhans Cell Histiocytosis

Ying Yang,Dong Wang,Lei Cui,Hong-Hao Ma,Li Zhang,Hong-Yun Lian,Qing Zhang,Xiao-Xi Zhao,Li-Ping Zhang,Yun-Ze Zhao,Na Li,Tian-You Wang,Zhi-Gang Li,Rui Zhang 대한암학회 2021 Cancer Research and Treatment Vol.53 No.1

Purpose We sought to investigate the effectiveness and safety of dabrafenib in children with BRAFV600E-mutated Langerhans cell histiocytosis (LCH). Materials and Methods A retrospective analysis was performed on 20 children with BRAFV600E-mutated LCH who were treated with dabrafenib. Results The median age at which the patients started taking dabrafenib was 2.3 years old (range, 0.6 to 6.5 years). The ratio of boys to girls was 2.3:1. The median follow-up time was 30.8 months (range, 18.9 to 43.6 months). There were 14 patients (70%) in the risk organ (RO)+ group and six patients (30%) in the RO– group. All patients were initially treated with traditional chemotherapy and then shifted to targeted therapy due to poor control of LCH or intolerance to chemotherapy. The overall objective response rate and the overall disease control rate were 65% and 75%, respectively. During treatment, circulating levels of cell-free BRAFV600E (cfBRAFV600E) became negative in 60% of the patients within a median period of 3.0 months (range, 1.0 to 9.0 months). Grade 2 or 3 adverse effects occurred in five patients. Conclusion Some children with BRAFV600E-mutated LCH may benefit from monotherapy with dabrafenib, especially high-risk patients with concomitant hemophagocytic lymphohistiocytosis and intolerance to chemotherapy. The safety of dabrafenib is notable. A prospective study with a larger sample size is required to determine the optimal dosage and treatment duration.

Analysis on the creep response of bolted rock using bolted burgers model

Zhao, Tong-Bin,Zhang, Yu-Bao,Zhang, Qian-Qing,Tan, Yun-Liang Techno-Press 2018 Geomechanics & engineering Vol.14 No.2

In this paper, the creep behavior of bolted rock was analyzed by using the unconfined creep tests and the numerical results. Based on the test results, the Bolted Burgers creep model (B-B model) was proposed to clarify the creep mechanism of rock mass due to rock bolts. As to the simulation of the creep behaviour of bolted rock, a new user-defined incremental iterative format of the B-B model was established and the open-source $FLAC^{3D}$ code was written by using the object-oriented language (C++). To check the reliability of the present B-B creep constitutive model program, a numerical model of a tunnel with buried depth of 1000 m was established to analyze the creep response of the tunnel with the B-B model support, the non-support and the bolt element support. The simulation results show that the present B-B model is consistent with the calculated results of the inherent bolt element in $FLAC^{3D}$, and the convergence deformation can be more effectively controlled when the proposed B-B model is used in the $FLAC^{3D}$ software. The big advantage of the present B-B creep model secondarily developed in the $FLAC^{3D}$ software is the high computational efficiency.

Identificaton and Analysis of Specific Fragments Associated with Cytoplasmic Male Sterility in Chinese Cabbage (Brassica campestris L. ssp. pekinensis)

Zhang De. Shuang,Zhang Feng. lan,Wang Yong. jian,Fang Zhi. yuan,Yu Yang Jun,Zhao Xiu Yun,Xu Jia Bing 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-

One-Pot Preparation of Graphene-Based Polyaniline Conductive Nanocomposites for Anticorrosion Coatings

Yun Zhao,Jiangquan Ma,Kun Chen,Chuandong Zhang,Chao Yao,Shixiang Zuo,Yong Kong 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.5

Graphene-based polyaniline (PANI/RGO), used as conductive filler, was synthesized through a new one-pot emulsion polymerization technology. Graphene dispersion (RGO) was obtained by ultrasonically reducing graphene oxide (GO) in a hot sodium hydroxide solution in the absence of any toxic reductant, such as hydrazine hydrate. Sodium dodecyl benzene sulfonate (SDBS), in which RGO sheets were dispersed, was synthesized using dodecyl benzenesulfonic acid (DBSA) and NaOH. In this RGO/SDBS mixture, polyaniline (PANI), doped with multiple acids (HClDBSA), was then uniformly polymerized on the surface of the RGO sheets. The experimental results showed that this reaction improved the dispersion of the RGO in the PANI system, and increased the homogeneous distribution of the formed PANI particles on the RGO surface. The synthesized composite material (PANI/RGO) had good thermal stability, electrical conductivity (about 11.71 S · cm -1) and water dispersibility. Based on its excellent properties, the PANI/RGO was combined with waterborne epoxy resin to prepare anticorrosion coatings. The corrosion resistance of these coatings was studied using Tafel plots, along with other critical properties tested by the national standards. The results suggested that the surface resistivity of the coatings could be as high as 2.48 X 10 8 Ω with the addition around 3 wt.% of the PANI/RGO meeting good antistatic standards. In addition, the antistatic coatings had outstanding corrosion resistance, as well as tremendous physical and chemical properties.

Fragrance Composition in Six Tree Peony Cultivars

Zhao, Jing,Hu, Zeng-Hui,Leng, Ping-Sheng,Zhang, Hui-Xiu,Cheng, Fang-Yun Korean Society of Horticultural Science 2012 원예과학기술지 Vol.30 No.6

Tree peony is a traditional famous flower of China, and plays an important role in Chinese traditional culture. But the floral scent of tree peony in vivo is little known. In this study, in order to explore the floral composition of tree peony, floral volatiles of six cultivars, including Paeonia suffruticosa 'Zhaofen' (ZF), P. suffruticosa 'Luoyanghong' (LYH), P. ostii 'Fengdanbai' (FDB), P. ${\times}$ lemonei 'High noon' (HN), P. ${\times}$ lemonei 'Renown' (R), and P. rockii 'Gaoyuanshenghuo' (GYSH) were collected by dynamic headspace and then identified by Automated Thermal Desorption-Gas Chromatography/Mass Spectometry. The results showed that floral fragrances of the six cultivars were qualitatively and quantitatively distinct. A total of 105 volatiles involving ten categories were detected. But not all volatile categories were emitted from these cultivars. The six peony cultivars emitted some shared compounds and peculiar compounds. The total released amounts of volatiles emitted from six cultivars were found significantly different, which was greatest for 'GYSH'. The most abundant volatile compounds detected from 'ZF', 'LYH', 'FDB', 'HN', 'R', and 'GYSH' were respectively ${\alpha}$-pinene, 2,3-dihydroxy propanal, 3-methyl-1-butanol, 2-ethyl-1-hexanol, acetic acid 1-methylethyl ester, and 5-ethyl-2,2,3-trimethyl heptane. This result may contribute to exploring the biosynthesis and emission mechanism of floral scent in tree peony.