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Manufacturing Error Effects on Mechanical Properties and Dynamic Characteristics of Rotor Parts under High Acceleration

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 920-932页

作者： Mei-Hui jia Cheng-Lin Wang Bin ren School of Logistics Beijing Wuzi UniversityBeijing 101149China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China

Stress, strain and vibration characteristics of rotor parts should be changed significantly under high acceleration, manufacturing error is one of the most important reason. However, current research on this prob- lem has not been carried out. A rotor with an acceleration of 150,000 g is considered as the objective, the effects of manufacturing errors on rotor mechanical properties and dynamic characteristics are executed by the selection of the key affecting factors. Through the force balance equation of the rotor infinitesimal unit establishment, a theoretical model of stress calculation based on slice method is pro- posed and established, a formula for the rotor stress at any point derives. A finite element model （FEM） of rotor with holes is established with manufacturing errors. The chan- ges of the stresses and strains of a rotor in parallelism and symmetry errors are analyzed, which verify the validity of the theoretical model. The pre-stressing modal analysis is performed based on the aforementioned static analysis. The key dynamic characteristics are analyzed. The results demonstrated that, as the parallelism and symmetry errors increase, the equivalent stresses and strains of the rotor slowly increase linearly, the highest growth rate does not exceed 4%, the maximum change rate of natural frequency is 0.1%. The rotor vibration mode is not significantlyaffected. The FEM construction method of the rotor with manufacturing errors can be utilized for the quantitative research on rotor characteristics, which will assist in the active control of rotor component reliability under high acceleration.

关键词： High acceleration Rotor Manufacturingerror Stress and strain Dynamic characteristics

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Synthesis, Spectroscopic, Thermochemical Properties of Lanthanide Complexes with 3,4-Diethoxybenzoic Acid and 1,10-Phenanthroline

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Chemical Research in Chinese Universities 2015年第6期31卷 1039-1045页

作者： QI Xiaoxia ren ning ZHANG Dahai ZHANG jianjun Testing and Analysis Center Hebei Normal University Shijiazhuang 050024 P. R. China College of Chemistry & Material Science Hebei Normal University Shijiazhuang 050024 P. R. China College of Chemical Engineering & Material Handan College Handan 056005 P. R. China

Three novel lanthanide complexes [Ln（3,4-DEOBA）3phen]2[Ln=Eu（1）, Tb（2）, Dy（3）; 3,4-DEOBA=3,4- diethoxybenzoate; phen=1,10-phenanthroline] were synthesized and characterized by elemental analysis, molar con- ductance, X-ray diffraction and infrared spectrometry. The luminescence spectra＇of complexes 1 and 2 show the cha- racteristic emission of EU^3＋ ion（^5D0→7F0-3） and Tb^3＋ ion（^5D4→^7F6-3）. The thermal decomposition mechanism of the title complexes and the analysis of the evolved gases were investigated by thermogravimetry/differential scanning calorimetry-Fourier transform infrared（TG/DSC-FTIR） technology. The results indicate the complexes are thermally stable. In the thermal decomposition of the complexes, phen molecules lost firstly, and then 3,4-DEOBA ligand de- composed into H20, CO2 and other gaseous molecules. Besides, several gaseous organic fragments were also detected. The heat capacities of complexes 1--3 were measured by DSC in a temperature range of 263.15--340.15 K. Based on the fitted polynomial and thermodynamic equations, the smoothed heat capacities and thermodynamic functions of the three complexes were calculated. The study on biological activity showed that the complexes exhibited good an- tibacterial activity against Candida albicans, Staphylococcus aureus and Escherichia coll.

关键词： Lanthanide complex Thermodynamics Thermal decomposition Heat capacity 3,4-Diethoxybenzoic acid

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Integrated agronomic practices management improved grain formation and regulated endogenous hormone balance in summer maize (Zea mays L.)

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Journal of Integrative Agriculture 2020年第7期19卷 1768-1776页

作者： YU ning-ning ZHANG Ji-wang LIU Peng ZHAO Bin ren Bai-zhao State Key Laboratory of Crop Biology Ministry of Science and Technology/College of AgronomyShandong Agricultural UniversityTai’an 271018P.R.China

Compared with single agronomic practices management during grain formation, knowledge about integrated agronomic practices management on grain-filling characteristics and physiological function of endogenous hormones was limited. In order to clarify this issue, two field experiments, integrated agronomic practices management(IAPM), T1(local conventional cultivation practices), T2(an optimized combination of cropping systems and fertilizer treatment), T3(treatment based on high-yield studies), and T4(further optimized combination of cropping systems and fertilizer treatment), and nitrogen rate testing(NAT)(four nitrogen rates, 0, 129.0, 184.5, and 300.0 kg N ha–1) were performed with summer maize hybrid Zhengdan 958(ZD958). Results showed that with increased nitrogen rate, the endogenous hormone balance was promoted and the grain-filling characteristics were improved sufficiently to resulting in a significant increase in grain yield. However, the grain-filling characteristics deteriorated and yield was reduced with excessive nitrogen fertilization. However, IAPM could promote hormone balance and improve grain filling characteristic. The indole-3-acetic acid(IAA), zeatin riboside(ZR), and gibberellin(GA3) contents under T2 and T4 treatments were higher and the abscisic acid(ABA) content was lower, and the ZR and GA3 contents under T3 were higher than those under T1. Those resulted in the maximum grain-filling rate(Wmax) and the active grain-filling period(P) under T2, T3 and T4 were significantly increased than those under T1, and hence promoted kernel weight and grain yield. So IAPM promoted hormone balance by improving tillage model, optimizing fertilizer rate and fertilization period, appropriately increasing planting density and delaying harvest, which promoted grain filling rate and lengthened active grain-filling period, finally increased grain yield.

关键词： grain fling endogenous hormone integrated agronomic practices management summer maize

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Three Types of Expression in Dark-Soliton Perturbation Theory Based on Squared Jost Solutions

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Communications in Theoretical Physics 2007年第1期47卷 15-18页

作者： AO Sheng-Mei YAN jia-ren College of Physics and Information Science Hunan Normal University Changsha 410081 China

Three types of expression in the dark-soliton perturbation theory based on squared Jost solutions are invesgigaged in ghis paper. It is shown that there are three formally different results about the effects of perturbagion on a dark soliton, and it is proved by means of a transformation between two integral variables that they are essentially equivalent.

关键词： dark soliton perturbation theory squared Jost solution soliton velocity first-order correction

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Expression of midkine and its clinical significance in esophageal squamous cell carcinoma

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World Journal of Gastroenterology 2006年第13期12卷 2006-2010页

作者： Ying-jia ren Qing-Yun Zhang Department of Immunology The School of Ontology Peking University Beijing Institute for Cancer Research Beijing 100036 China Department of Medical Laboratory Beijing Cancer Hospital Beijing 100036 China

AIM： To investigate the expression of midkine in eso- phageal squamous cell carcinoma （ESCC） and analyze its relationship with clinicopathological features. METHODS： RT-PCR and immunocytochemical staining were used to detect the expression of midkine mRNA and protein in EC109 cells, respectively. Then the expression of midkine in 66 cases of ESCC samples were detected by immunohistochemistry using monoclonal antibodies against human midkine. RESULTS： Midkine was expressed in EC109 cell by RT- PCR and imrnunocytochemistry. The immunoreactivity was detected in 56.1% （37/66） of the ESCC samples. The expression of midkine was found in cytoplasm of tumor cells. Notably, the intensity of midkine was stronger at the area abundant in vessels and the invading border of the tumors. Midkine was more intensely expressed in well differentiated tumors （76.9 %） than in moderately and poorly differentiated tumors （43.1% and 41.2%, respectively）（P〈0.05）. There was no statistically significant correlation between midkine expression and gender, age, clinical stage, lymph node metastasis or survival in ESCC. CONCLUSION： IVlidkine is overexpressed in ESCC. It may play a role in tumor angiogenesis and invasion. The expression of midkine is correlated with tumor cell differentiation in ESCC. The more poorly tumor cells differentiate, the weaker midkine expresses.

关键词： Midkine Esophageal squamous cell carcinoma Expression

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Global Probabilistic Voltage Sensitivity Analysis of Active Distribution Networks Based on the Compound Gaussian Mixture Model

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Dianwang Jishu/Power System Technology 2025年第1期49卷 295-305页

作者： Zhang, ren Wang, jian Shang, Jie Hai, Chen Liu, Haoming School of Electrical and Power Engineering Hohai University Jiangsu Province Nanjing 211100 China College of Artificial Intelligence and Automation Hohai University Jiangsu Province Nanjing 211100 China

The stochasticity of the high penetration of distributed generations (DGs) exacerbates the voltage fluctuation of the active distribution networks (ADNs) and complicates its voltage safety analysis. Therefore, this paper proposes a global probability voltage sensitivity analysis method based on the compound Gaussian mixture model (GMM). Firstly, a shared node path impedance-based global voltage sensitivity analytical model of ADN is derived to quantify the impact of global power fluctuations on node voltage. Considering that the voltage fluctuation has the non-Gaussian characteristic under the superposition influence of power uncertainty injected by multiple nodes, the GMM is used to characterize the probability characteristics of DG and load forecasting errors. Then, based on the affine transformation of the global sensitivity matrix to the GMM of DG and load forecasting error, the probability analytic expression of the voltage fluctuation is constructed, which is caused by the uncertainty of DG and load. Finally, based on the GMM characteristic function, the compound GMM characteristic function of the combined influence of the uncertainty of DG and load on voltage fluctuation is derived, and the global probabilistic voltage sensitivity analysis model based on the compound GMM is established. The case study results show that the proposed method can reflect the probability characteristics of the impact of all node power fluctuations on node voltage, and can quickly and accurately calculate the probability of over-voltage in ADNs. © 2025 Power System Technology Press. All rights reserved.

关键词： Affine transforms

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The Weyl’s Theorem and Its Perturbations in Semisimple Banach Algebra

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Acta Mathematica Sinica,English Series 2021年第5期37卷 675-688页

作者： Ying Ying KONG Li ning jiaNG Yan Xun ren School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081P.R.China

Denote a semisimple Banach algebra with an identity e by *** paper studies the Fredholm,Weyl and Browder spectral theories in a semisimple Banach algebra,and meanwhile considers the properties of the Fredholm element,the Weyl element and the Browder ***,for a∈A,we give the Weyl’s theorem and the Browder’s theorem for a,and characterize necessary and sufficient conditions that both a and f(a)satisfy the Weyl’s theorem or the Browder’s theorem,where f is a complex-valued function analytic on a neighborhood ofσ(a).In addition,the perturbations of the Weyl’s theorem and the Browder’s theorem are investigated.

关键词： Semisimple Banach algebra Fredholm element Browder element Weyl’s theorem perturbation

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LIPUS Enhance Elongation of Neurites in Rat Cortical Neurons through Inhibition of GSK-3β

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Biomedical and Environmental Sciences 2010年第3期23卷 244-249页

作者： CONG ren jia-MOU LI XIN LIN Department of Orthopedics Beijing Tiantan Hospital Capital Medical University Beijing 100050 China

Objective Low-intensity pulsed ultrasound （LIPUS） has been reported to enhance proliferation and to alter protein production in various kinds of cells. In the present study, we measured the neurites length after LIPUS treatment to define the effectiveness of LIPUS stimulation on neurons, and then we examined the acticity of GSK-3β to study the intracellular mechanism of neurite＇s outgrowth. Methods LIPUS was applied to cultured primary rat cortical neurons for 5 minutes every day with spatial- and temporal average intensities （SATA） of 10 mW/cm^2, a pulse width of 200 microseconds, a repetition rate of 1.5 KHz, and an operation frequency of 1 MHz. Neurons were photographed on the third day after LIPUS treatment and harvested at third, seventh, and tenth days for immnoblot and semi-quantitative RT-PCR analysis. Results Morphology change showed that neurite extension was enhanced by LIPUS. There was also a remarkable decrease of proteins, including p-Akt, p-GSK-3β, and p-CRMP-2, observed on the seventh and tenth days, and of GSK-3β mRNA expression, observed on the seventh day, in neurons treated with LIPUS. Conclusion LIPUS can enhance elongation of neurites and it is possible through the decreased expression of GSK-3β.

关键词： LIPUS Rat cortical neurons GSK-3β

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Radical cation salts induced domino reaction of anilines with enol ethers:Synthesis of 1,2,3,4-tetrahydroquinoline derivatives

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Chinese Chemical Letters 2011年第6期22卷 671-674页

作者： Xiao Dong jia Yan ren Cong Dde Huo Wen Juan Wang Xiang ning Chen Qiong Fu Xi Cun Wang Key Laboratory of Eco-Environment-Related Polymer Materials Ministry of EducationGansu Key Laboratory of Polymer Materials College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China

A domino reaction of anilines with cyclic and acyclic enol ethers induced by catalytic amounts of TBPA^（·＋）（5 mol%） was investigated and a series of 2,4-disubstituted-1,2,3,4-tetrahydroquinolines were *** from cyclic enol ethers, when acyclic enol ethers were used in the reaction,they serve as surrogates of acetaldehyde,producing a series of 2-methyl-4- anilino-1,2,3,4-tetrahydroquinolines.A single electron transfer mechanism was proposed to rationalize the products formation.

关键词： Domino reaction Radical cation salts 1 2 3 4-Tetrahydroquinoline Enol ether

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Microstructure and texture evolution of Cu-Cr-Co-Ti alloys during the two-stage cryorolling

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Rare Metals 2024年第9期43卷 4535-4547页

作者： jia-Jun Zhang Long-jian Li Zhi-Feng Liu Zong-ning Chen En-Yu Guo Hui-Jun Kang ren-Geng Li Tong-Min Wang Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Center of Hyper-Gravity Experimental and Interdisciplinary Research Zhejiang UniversityHangzhou 310058China ningbo Institute of Dalian University of Technology Ningbo 315000China Key Laboratory for Light-Weight Materials Nanjing Tech UniversityNanjing 210009China

This study entailed an investigation of the mechanical properties,microstructural and texture orientation evolutions of Cu-Cr-Co-Ti alloys prepared via twostage cryorolling and intermediate aging *** this end,X-ray diffraction and electron backscatter diffraction were *** results indicate that the two-stage cryorolling and intermediate aging treatments led to the development of profuse twin bundles and significantly enhanced the mechanical *** initial cryorolling led to coplanar slip and developed a strong Y({111})orientation,accelerating the formation of Goss({011})orientation and a Brass-type *** intermediate aging treatment relieved the restriction on dislocation slip and reoriented the grains toward the Copper({112})and Z({111})*** Z orientation,with a relatively high volume fraction,dominated the *** cryorolling intensified twinning and shear banding,transforming the Copper-type shear bands into Brass-type shear bands with rhomboidal prism *** areas inside the Brasstype shear bands exhibited a Y orientation,and the areas outside the shear bands exhibited a stable Brass-type *** evident decrease in the weighted Schmid factors demonstrated that the two-stage cryorolling and intermediate aging treatment can modify the texture evolution and aid the design of high-performance Cu alloys.

关键词： Copper alloys Two-stage cryorolling Macrotexture evolution Electron backscatter diffraction Schmid factor

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