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Chinese Chemical Letters 2014年第5期25卷 752-756页

作者： qing-Yun Liu qing-Yan Jia Ji-qin Zhu qian Shao Jun-Feng Fan Dong-Mei Wang Yan-Sheng Yin College of Chemistry and Chemical Engineering Ocean University of China College of Chemical and Environmental Engineering Shandong University of Science and Technology Institute of Marine Materials Science and Engineering Shanghai Maritime University

meso-Tetrakis（4-aminophenyl）porphyrin（TAPP） can self-assemble into nanostructures with different morphologies by a phase-transfer *** morphologies（nanospheres,nanorods and nanothorns）of porphyrin nanoaggregates could be easily tuned just by changing the concentration of porphyrin in a proper solvent at room *** images revealed the formation of highly ordered supramolecular arrays of TAPP,i.e. superlattice of TAPP molecules in nanoaggregates,which agreed well with the size of one molecule of ***–vis absorption spectra showed an obvious red shift of the Soret band of TAPP,indicating the formation of J-aggregates of TAPP in nanoaggregates.

关键词： Porphyrin Self-assembly Nanoaggregates Highly ordered Hydrogen bonding

Wear Resistance, Cytotoxicity and Antibacterial Properties of Polyetheretherketone Composite Modified by Carbon Fiber and Black Phosphorus

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Journal of Bionic Engineering 2022年第1期19卷 155-166页

作者： Jingdan Li qian Liang Wen qin Jing Ma School of Material Science and Engineering Taiyuan University of TechnologyTaiyuan030024China

High wear resistance,low cytotoxicity and excellent antibacterial properties are the basis for osseointegration of implant ***(PEEK)has been considered as a potential implant material due to its excellent biocompatibility,natural radiolucency and mechanical *** this work,to improve the wear resistance,cytotoxicity and antibacterial properties of PEEK,carbon fiber(CFR)and Black Phosphorus(BP)were used to synergistically modify PEEK by two methods,deposition of BP coating on CFR-PEEK and BP/CFR-PEEK coating on Ti6Al4V(TC4)through electrostatic *** CFR and BP synergistically modified PEEK,the friction coefficient of BP coating on CFR-PEEK and BP/CFR-PEEK coating were 0.14±0.01 and 0.09±0.02,*** wear volume of BP coating on CFR-PEEK(30.54±1.32)was higher than that of BP/CFR-PEEK coating(9.46±1.32),which indicated that BP/CFR-PEEK coating showed high wear *** difference in wear resistance may be caused by the fact that BP was not easily oxidized in BP/CFR-PEEK *** addition,BP coating on CFR-PEEK and BP/CFR-PEEK coating showed no obvious cytotoxicity to L929 cell and presented excellent antibacterial efficiency(up to 94.5%±2.8%and 96.0%±3.8%,respectively)against Staphylococcus aureus(***).It was concluded that BP/CFR-PEEK coating exhibited high wear resistance,low cytotoxicity and excellent antibacterial properties against ***,which might provide a foundation for osseointegration of implants.

关键词： Surface deposition Electrostatic spraying Wear resistance Cytotoxicity Antibacterial properties

A practical filter error method for aerodynamic parameter estimation of aircraft in turbulence

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Chinese Journal of Aeronautics 2023年第2期36卷 17-28页

作者： qing WANG Fengqi ZHENG Weiqi qian Di DING State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China Computational Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 62100China

It is common for aircraft to encounter atmospheric turbulence in flight *** is usually modeled as stochastic process noise in the flight dynamics *** this paper,parameter estimation of nonlinear dynamic system with both process and measurement noise was studied,and a practical filter error method was *** linearized Kalman filter of first-order approximation was used for state estimation,in which the filter gain,along with the system parameters and the initial states,constituted the parameter vector to be *** unknown parameters and measurement noise covariance were estimated alternately by a relaxation iteration method,and the sensitivities of observations to unknown parameters were calculated by finite difference *** practical aspects of the method application were *** proposed filter error method was validated by the flight simulation data of a research ***,the method was applied to the flight tests of a subscale aircraft,and the aerodynamic stability and control derivatives were *** the estimation results were compared with the results of the output error method to demonstrate the effectiveness of the *** is shown that the filter error method is superior to the output error method for flight tests in atmospheric turbulence.

关键词： Aircraft aerodynamics Atmosphere turbulence Flight tests Kalman filter Maximum likelihood estimation Measurement noise Parameter estimation Stability and control derivatives

Prevalence and characteristics of MAFLD in Chinese adults aged 40 years or older:A community-based study

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Hepatobiliary & Pancreatic Diseases International 2022年第2期21卷 154-161页

作者： Jing Zeng Li qin qian Jin Rui-Xu Yang Guang Ning qing Su Zhen Yang Jian-Gao Fan Department of Gastroenterology Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200092China Department of Endocrinology Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200092China Department of Endocrine and Metabolic Diseases Shanghai Institute of Endocrinology and MetabolismShanghai Clinical Center for Endocrine and Metabolic DiseasesRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China

Background: Nonalcoholic fatty liver disease(NAFLD) was recently proposed to be renamed metabolic dysfunction-associated fatty liver disease(MAFLD) with the diagnostic criteria revised. We investigated the similarities and differences in the prevalence and clinical characteristics of MAFLD and NAFLD in Chinese adults. Methods: A cross-sectional study of 9980 Chinese individuals aged 40 years or older was performed between 2011 and 2012 using randomized, stratifed cluster sampling in Shanghai, China. A detailed questionnaire and the results of abdominal ultrasonography, a standardized 2-h 75-g oral glucose tolerance test and blood biochemical examinations were collected. Results: A total of 9927 subjects were included in this study. The prevalence of MAFLD(40.3%) was significantly higher than that of NAFLD(36.9%)( P < 0.05). MAFLD was highly prevalent in type 2 diabetes mellitus(T2DM)(53.8%), impaired fasting glucose(35.7%) and impaired glucose tolerance(40.9%). High risk of advanced fbrosis based on fbrosis-4 was highly prevalent(14.7%) in lean MAFLD with T2DM. Among 9927 subjects, 3481(35.1%) fulflled the diagnostic criteria for MAFLD and NAFLD(MAFLD + NAFLD +), 521(5.2%) MAFLD + NAFLD-, and 181(1.8%) MAFLD-NAFLD +. The MAFLD + NAFLD-group had more signifcant metabolic disorders than those in the MAFLD + NAFLD + group(all P < 0.05). Among MAFLD-NAFLD + subjects, 82.9% had metabolic disorders. Conclusions: The new defnition of MAFLD may better reflect the pathogenesis related to metabolism. Future research should focus on studying the natural history, pathogenesis and treatment effectivity of the overlap and non-overlap of NAFLD and MAFLD subjects.

关键词： Nonalcoholic fatty liver disease Metabolic dysfunction-associated fatty liver disease Prevalence Oral glucose tolerance test

Empirical Likelihood Confidence Intervals for the Differences of Quantiles with Missing Data

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 105-116页

作者： Yong-song qin Yong-jiang qian School of Mathematical Sciences Guangxi Normal University Guilin Guangxi 541004 China

Suppose that there are two nonparametric populations x and y with missing data on both of them. We are interested in constructing confidence intervals on the quantile differences of x and y. Random imputation is used.... 详细信息

关键词： Empirical likelihood confidence Interval quantile missing data imputation

Parametric study of control mechanism of cortical bone remodeling under mechanical stimulus

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Acta Mechanica Sinica 2010年第1期26卷 37-44页

作者： YananWang qing-Hua qin Department of Engineering Australian National UniversityCanberra ACT 0200 Australia

The control mechanism of mechanical bone remodeling at cellular level was investigated by means of an extensive parametric study on a theoretical model described in this paper. From a perspective of control mechanism, it was found that there are several control mechanisms working simultaneously in bone remodeling which is a complex process. Typically, an extensive parametric study was carried out for investigating model parameter space related to cell differentiation and apoptosis which can describe the fundamental cell lineage behaviors. After analyzing all the combinations of 728 permutations in six model parameters, we have identified a small number of parameter combinations that can lead to physiologically realistic responses which are similar to theoretically idealized physiological responses. The results presented in the work enhanced our understanding on mechanical bone remodeling and the identified control mechanisms can help researchers to develop combined pharmacological-mechanical therapies to treat bone loss diseases such as osteoporosis.

关键词： Control mechanism Parametric study Mechanical bone remodeling

VIBRATION AND STABILITY OF VERTICAL UPWARD-FLUID-CONVEYING PIPE IMMERSED IN RIGID CYLINDRICAL CHANNEL

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Acta Mechanica Solida Sinica 2008年第5期21卷 431-440页

作者： qin qian Lin Wang Qiao Ni Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China

A theoretical model is developed for the vibration and stability of a vertical pipe subjected concurrently to two dependent axial flows. The external fluid, after exiting the outer annular region between the pipe and a rigid cylindrical channel, is conveyed upwards inside the pipe. This configuration thus resembles of a pipe that aspirating fluid. The equation of planar mo- tion is solved by means of the differential quadrature method （DQM）. Calculations are conducted for a slender drill-string-like and a bench-top-size system, for different confinement conditions of the outer annular channel. It is shown that the vibrations of these two systems are closely related to the degree of confinement of the outer annular channel. For a drill-string-like system with narrow annuli, buckling instability may occur in the second and third modes. For a bench-top-size system, however, both buckling and flutter may occur in the lowest three modes. The form of instability depends on the annuli size.

关键词： pipe conveying fluid annular flow axial flow drill-string stability critical flow velocity

快速气相色谱法测定汽油单体烃组成及多项物性预测模型的建立

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石油炼制与化工 2025年第1期56卷 172-180页

作者：李长秀王亚敏张祎玮王征钱钦中石化石油化工科学研究院有限公司北京100083

建立了采用40 m×0.10 mm×0.20μm超细内径非极性色谱柱、氢气作载气的快速分析汽油馏分单体烃组成的方法(简称快速单体烃分析方法)。对于催化裂化汽油C_(3)~C_(12)组分可以得到367个色谱峰,正十二烷的保留时间为30.1 min。同一样品重... 详细信息

建立了采用40 m×0.10 mm×0.20μm超细内径非极性色谱柱、氢气作载气的快速分析汽油馏分单体烃组成的方法(简称快速单体烃分析方法)。对于催化裂化汽油C_(3)~C_(12)组分可以得到367个色谱峰,正十二烷的保留时间为30.1 min。同一样品重复测定3次的结果显示组分保留时间极差小于0.02 min,保留指数极差小于0.50。对于质量分数大于0.5%的单体烃组分,含量测定结果的相对标准偏差小于6%;对于质量分数小于0.5%的单体烃组分,含量测定结果的相对标准偏差小于10%。建立了根据汽油单体烃分析结果计算汽油的密度、饱和蒸气压、折射率、碳氢元素含量、平均相对分子质量、溴值的修正计算模型。根据修正模型计算样品的密度、折射率和饱和蒸气压,计算结果与实测结果有较好的一致性。根据快速单体烃分析方法的测定结果和采用50 m×0.20 mm×0.50μm非极性色谱柱的常规单体烃分析方法的测定结果计算多项物性参数,两种方法下的计算结果一致,说明建立的计算模型也适用于采用快速单体烃分析方法的测定结果计算样品的多项物性参数。

关键词：汽油单体烃快速分析气相色谱物性参数

Intelligent Silent Zone for Source-Location Privacy Based on Context-Awareness in WSNs

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第1期35卷 203-218页

作者： Zhou qian qin Xiaolin Ding Youwei College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China Jiangsu Key Laboratory of Internet of Things and Control Technology Nanjing 211106P.R.China

In many wireless sensor networks(WSNs)applications,the preservation of source-location privacy plays a critical role in concealing context information,otherwise the monitored entities or subjects may be put in *** traditional solutions have been proposed based on the creation of random routes,such as random walk and fake sources approach,which will lead to serious packet delay and high energy *** of applying the routing in a blind way,this article proposes a novel solution for source location privacy in WSNs by utilizing sensor ability of perceiving the presence a mobile attacker nearby,for patient attackers in particular to increase the safety period and decrease the data delivery *** proposed strategy forms an intelligent silent zone(ISZ)by sacrificing only a minority of sensor nodes to entice patient attackers away from real packet routing *** analysis and simulation results show that the proposed scheme,besides providing source location privacy energy efficiently,can significantly reduce real event reporting latency compared with the existing approaches.

关键词： source location privacy wireless sensor networks energy-efficiency context-aware

NONLINEAR RESPONSES OF A FLUID-CONVEYING PIPE EMBEDDED IN NONLINEAR ELASTIC FOUNDATIONS

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Acta Mechanica Solida Sinica 2008年第2期21卷 170-176页

作者： qin qian Lin Wang Qiao Ni Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China

The nonlinear responses of planar motions of a fluid-conveying pipe embedded in nonlinear elastic foundations are investigated via the differential quadrature method discretization （DQMD） of the governing partial differential equation. For the analytical model, the effect of the nonlinear elastic foundation is modeled by a nonlinear restraining force. By using an iterative algorithm, a set of ordinary differential dynamical equations derived from the equation of motion of the system are solved numerically and then the bifurcations are analyzed. The numerical results, in which the existence of chaos is demonstrated, are presented in the form of phase portraits of the oscillations. The intermittency transition to chaos has been found to arise.

关键词： fiuid-conveying pipe nonlinear elastic foundation chaotic motion bifurcation differential quadrature method discretization (DQMD)