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Effects of process parameters on periodic impact force exerting on cutting tool in ultrasonic vibration-assisted oblique turning

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Advances in Manufacturing 2022年第3期10卷 411-427页

作者： Long-Xu yao Zhan-Qiang Liu Qing-hua Song Bing Wang yu-Kui Cai School of Mechanical Engineering Shandong UniversityJinan 250061People's Republic of China Key Laboratory of High Efficiency and Clean Mechanical Manufacture of Ministry of Education/Key National Demonstration Center for Experimental Mechanical Engineering Education Jinan 250061People's Republic of China

During ultrasonic vibration-assisted machining,the large impact force induced by tool-workpiece reengagement(TWR)is an important factor that affects tool ***,mechanical analysis into process factors that affect the impact force and their influencing mechanisms are ***,a prediction model for the instantaneous cutting force during both TWR and the stable turning process,which depends on the process parameters and material properties,is firstly proposed based on the kinematic and dynamic analysis of ultrasonic vibration-assisted oblique turning(UVAOT).The results calculated using the developed cutting force model agree well with the experimental results presented in the ***,the linear change law of the instantaneous cutting force with cutting time during the actual TWR is clarified using the proposed *** effect of the UVAOT process parameters on the average impact force during the periodic TWR process is discussed,and the influence mechanism is analyzed from the perspective of mechanics.A positive linear correlation is discovered between the feed speed and average impact *** ultrasonic amplitude and cutting speed do not significantly affect the average impact force of the new sharp cutting *** findings are consistent with the experimental observations of tool chipping and are applicable to select process parameters for reducing tool chipping during UVAOT.

关键词： Kinematics Dynamics Ultrasonic vibrationassisted oblique turning(UVAOT) Impact force Cutting force

Properties of Titanium isotopes in complex momentum representation within relativistic mean-field theory

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Nuclear Science and Techniques 2022年第9期33卷 93-100页

作者： Tai-hua Heng yao-Wu Chu School of Physics and Optoelectronic Engineering Anhui UniversityHefei 230601China

The self-consistent quadruple potential is deduced within the relativistic mean-field(RMF)framework and substituted into the Hamiltonian,which is calculated using the complex momentum representation(CMR).Considering even-even titanium isotopes as an example,this study investigated various properties,including the resonant states of neutron-rich nuclei in the RMF-CMR model,and used them to describe the binding *** abrupt decrease in the two-neutron separation energy(S_(2n))corresponds to the traditional magic *** resonant and bound states are simultaneously exposed in the complex moment plane,where the continuum is along the integration *** four oblate neutron-rich nuclei^(72-78)Ti are weakly bound or resonant because their Fermi energies are approximately 0 *** root-meansquare(RMS)radii of these nuclei increase suddenly compared with those of others(neutron number N<48).Moreover,^(78)Ti and^(76)Ti are determined as drip-line nucleons by the value of S_(2n) and the energy levels,***,the weak-bounded character can be represented by diffuse density probability distributions.

关键词： Resonant states Self-consistent potential Complex momentum representation

Preparation and Visible-Light Photocatalytic Activity of FeTPP-Cr-TiO2 Microspheres

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Chinese Journal of Chemical Physics 2016年第6期29卷 717-724,I0002页

作者： Bing-hua yao Chao Peng Yang-qing He Wen Zhang Yan yu Ting Zhang DepartmentofAppliedChemistry XianUniversityofTechnologyXi'an710048China DepartmentofCivilEngineering UniversityofArkansasFayetteville72701USA SchoolofMaterialsScienceandEngineering XianUniversityofTechnologyXi'an710048China

Tetraphenyl-porphyrin iron （FeTPP） was chosen to sensitize Cr doped TiO2 （Cr-TiO2） nanoparticles, a novel multimodified photocatalyst FeTPP-Cr-TiO2 with excellent visible- light photocatalytic activity was successfully synthesized. The FeTPP-Cr-TiO2 microspheres were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electronic microscopy, X-ray photoelectron spectroscopy, UV-Vis diffuse reflectance spectra and N2 adsorption-desorption isotherms. The photocatalytic activity of FeTPP-Cr-TiO2 was evaluated by degradations of methylene blue in aqueous solution under irradiation with Xe lamp （150 W）. The results showed that the FeTPP-Cr-TiO2 multimodified photocatalyst was anatase phase with high specific surface area （74.7 m^2/g）, and exhibited higher photocatalytic degradation efficiency than Cr-TiO2 and FeTPP-TiO2. The photocatalytic degradations of three quinolone antibiotics （lomefioxacin, norfioxacin, and ofioxacin） were further estimated for the feasibility of practical application of catalyst in wastewater treatment. It is desirable that photodegradation of antibiotics with FeTPP-Cr-TiO2 achieved pretty high degradation rates and all followed the pseudo first-order reaction model, and the rate constants k of 3.02×10^-2, 2.81×10^-2, and 3.86×10^-2 min-1 and the half-lifes t1/2 of 22.9, 24.6, and 17.9 min were achieved respectively.

关键词： Titanium dioxide Chromium doping Metalloporphyrin Multimodified pho-tocatalyst Visible-light photocatalysis Antibiotics

Research on hybrid multi-terminal high-voltage DC technology for offshore wind farm integration

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Journal of Modern Power Systems and Clean Energy 2013年第1期1卷 34-41页

作者： Peng ZHAN Chenghao LI Jinyu WEN yu hua Meiqi yao Naihu LI State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and TechnologyWuhan 430074Chin Grid Technology Center(China)Co.Ltd. Shanghai 201114China

Multi-terminal high-voltage DC(MTDC)technology is a promising way to transmit large amounts of offshore wind power to the main *** paper proposes a hybrid MTDC scheme to integrate several offshore wind farms into the onshore power grids at different locations.A hybrid four-terminal HVDC system comprising two onshore line commutated converters(LCCs)and two voltage source converters(VSCs)connecting an offshore wind farm is constructed in PSCAD/EMTDC.A coordination control scheme based on the VSCs’AC voltage control and the LCCs’DC voltage droop control is designed to ensure smooth system operation and proper power sharing between onshore AC *** operational characteristics of the system are *** addition,a black start-up method without any auxiliary power supply for the VSCs is *** transmission scheme is tested through simulations under various conditions,including start-up,wind speed variation,and the disconnection of one VSC or of one LCC.

关键词： Hybrid multi-terminal HVDC Offshore wind farm Droop control Voltage source converter Line commutated converter

Formation of infinite 2D water layers in a crystal host

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Chinese Chemical Letters 2009年第7期20卷 861-864页

作者： Cai hua Zhou Li Jun Zhou Long Tang yao yu Wang Department of Chemistry & Chemical Engineering Yan'an University Yan'an 716000 PR China Department of Chemistry/Shaanxi Key Laboratory of Physico-inorganic Chemistry Northwest University Xi'an 710069 PR China Department of Applied Chemistry Xidian University Xi'an 710071 PR China

A self-assembled, （H20）38 cluster stabilized by a mono-nuclear copper（H） complex 1 namely { [Cu（phen）2（CO3）].7H2O} is characterized by X-ray diffraction studies. The adjacent （H2O）38 clusters connect together resulting in an infinite 2D water layer structure. The water morphology is stable at room temperature, but upon thermal decomposition, the water loss is irreversible. C 2009 Cai hua Zhou. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Water cluster Supramolecular Hydrogen-bonding

Endemic medicinal plant distribution correlated with stable climate,precipitation,and cultural diversity

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Plant Diversity 2023年第4期45卷 479-484页

作者： Gang Feng Ying-Jie Xiong hua-yu Wei yao Li Ling-Feng Mao Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau&Inner Mongolia Key Laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhotChina Co-Innovation Center for Sustainable Forestry in Southern China College of Biology and the EnvironmentNanjing Forestry UniversityNanjingChina

Medicinal plants provide crucial ecosystem services,especially in developing countries such as China,which harbors diverse endemic medicinal plant species with substantial cultural and economic ***,understanding the patterns and drivers of medicinal plant distribution is ***,few studies have investigated the patterns and drivers of endemic medicinal plants distribution in ***,we linked endemic medicinal plants distribution with possible explanatory variables,i.e.,paleoclimate change,contemporary climate,altitudinal range and ethnic minority human population size at the prefecture city level in *** results show that endemic medicinal plants are concentrated in southern China,especially in southwestern ***,both endemic medicinal plant species richness and the ratio of endemic medicinal plant species richness are negatively associated with glacialinterglacial anomaly in temperature,and positively associated with contemporary precipitation and altitudinal *** addition,we found that endemic medicinal plant species richness is positively associated with ethnic minority population sizes as well as its ratio to the overall population *** findings suggest that the distribution of endemic medicinal plants is determined by multiple ***,our findings stress that dramatic future climate changes and massive anthropogenic activities in southern China pose great challenges to the conservation of China's endemic medicinal plants.

关键词： Altitudinal range Cultural diversity Endemic medicinal plant Glacial-interglacial climate change Precipitation Spatial distribution

MdMYB8 is associated with flavonol biosynthesis via the activation of the MdFLS promoter in the fruits of Malus crabapple

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Horticulture Research 2020年第1期7卷 2552-2564页

作者： hua Li yu Li Jiaxuan yu Ting Wu Jie Zhang Ji Tian yuncong yao Beijing Advanced Innovation Center for Tree Breeding by Molecular Design Beijing University of AgricultureBeijingChina Department of Plant Science and Technology Beijing University of AgricultureBeijingChina College of Horticulture China Agricultural UniversityBeijingChina

Flavonols are polyphenolic compounds that play important roles in plant stress resistance and *** are also valuable components of the human *** Malus crabapple cultivar‘Flame’provides an excellent model for studying flavonol biosynthesis due to the high flavonol content of its fruit *** obtain a more detailed understanding of the flavonol regulatory network involved in fruit development,the transcriptomes of the fruit of the Malus cv.‘Flame’from five continuous developmental stages were analyzed using RNA sequencing.A flavonol-related gene module was identified through weighted gene coexpression network analysis(WGCNA),and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis indicated that phytohormones are involved in regulating flavonol biosynthesis during fruit development.A putative transcription factor,MdMYB8,was selected for further study through hub gene correlation network analysis and yeast one-hybrid *** overexpression or RNAi knockdown of MdMYB8 in transgenic‘Orin’apple calli resulted in a higher or lower flavonol content,respectively,suggesting that MdMYB8 is a regulator of flavonol *** transcriptome analysis provides valuable data for future studies of flavonol synthesis and regulation.

关键词： activation synthesis network

Character Formulas for a Class of Simple Restricted Modules over the Simple Lie Superalgebras of Witt Type

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Chinese Annals of Mathematics,Series B 2020年第1期41卷 49-60页

作者： yu-Feng yao Department of Mathematics Shanghai Maritime UniversityShanghai 201306China

Let F be an algebraically closed field of prime characteristic, and W(m, n, 1) be the simple restricted Lie superalgebra of Witt type over F, which is the Lie superalgebra of superderivations of the superalgebra ■(m;1) ■∧(n), where ■(m;1) is the truncated polynomial algebra with m indeterminants and ∧(n) is the Grassmann algebra with n indeterminants. In this paper, the author determines the character formulas for a class of simple restricted modules of W(m, n, 1) with atypical weights of type Ⅰ.

关键词： Restricted Lie superalgebra Witt type Lie superalgebra Restricted representation Typical(atypical) weight Character formula

Analysis of the effect of repair materials for orbital blowout fracture on complications

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International Journal of Ophthalmology(English edition) 2019年第11期12卷 1746-1750页

作者： Qi-hua Xu Jin-Hai yu yao-hua Wang An-An Wang Hong-Fei Liao Department of Ocular Trauma Orbital DiseaseAffiliated Eye Hospital of Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Jiangxi Research Institute of Ophthalmology&Visual Sciences Nanchang 330006Jiangxi ProvinceChina

AIM: To investigate the effect of repair materials for orbital blowout fractures on the occurrence of postoperative complications. METHODS: The clinical data and follow-up data of 54 subjects with orbital blowout fractures were retrospectively analyzed. The study was divided into three groups according to the used repair materials: titanium mesh(16 cases), Medpor(12 cases), and Medpor titanium mesh(26 cases). All test data were analyzed using the SPSS version 23.0 statistical software. The mean age and duration of disease between the groups were compared through oneway analysis of variance. The Chi-square(χ~2) test was used to compare the number of males and females, different fracture types, and different surgical approaches among groups. The χ~2 test was used to compare the frequencies for complications in each ***: The baseline characteristics of age and gender in each group were matched(F=1.763, P=0.172;χ~2=0.026, P=0.987). In addition, there was no difference in the type of fracture and surgical approach(χ~2=0.460, P=0.977;χ~2=0.691, P=0.952), or the incidence of complications(χ~2=0.081, P=0.960) between the three groups. CONCLUSION: Although there is no difference in effect of various repair materials on the incidence of complications, the effect of repair materials on postoperative complications of orbital blowout fractures should not be ignored.

关键词： orbital blowout fracture repair materials postoperative complications