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Evaluating the lifetime performance index with the inverted exponentiated Rayleigh distribution based on censored sample

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International Journal of Modeling, Simulation, and Scientific Computing 2019年第5期10卷 15-33页

作者： shuo gao Wenhao Gui Department of Mathematics Beijing Jiaotong University Beijing 100044P.R.China

Lifetime performance index is a powerful and effective way to analyze whether a product achieves the specified *** this paper,we investigate the lifetime performance index for the inverted exponential Rayleigh distribution using progressive type II censored sample *** censored sample is able to greatly save the cost of the experiment and speed up the *** derive the estimation value of lifetime performance index using the maximum likelihood method,and conduct the hypothesis *** on extensive numerical simulation,the power function is utilized to assess effectiveness of hypothesis *** simulation results show that lifetime performance index is good for determining whether the lifetime of the product reaches the ***,a practical dataset is provided to give a demonstration for the procedures of lifetime performance evaluation.

关键词： Maximum likelihood estimation lifetime performance index progressive type II censoring Monte Carlo simulation power function inverted exponentiated Rayleigh distribution

Performance Analysis of Cooling Wall of Supercritical CO_(2) Coal-Fired Plants

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Journal of Thermal Science 2022年第6期31卷 1881-1890页

作者： WANG Yanjuan YU Binhui gao shuo LIU Qibin XU Jinliang The Beijing Key Laboratory of Multiphase Flow and Heat Transfer North China Electric Power UniversityBeijing 102206China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Using supercritical CO_(2)(S-CO_(2)) instead of water steam as heat transfer fluid for coal-fired power plants is another way to further improve the power generation efficiency. In this paper, a multi-field coupling model that integrates fluid flow, heat transfer and thermal stress is proposed to solve the complex problem. The effects of the key operating parameters on the performances of the cooling wall are numerically investigated. More details of the characteristics of fluid dynamics, thermal stress, pressure drop, coupled heat transfer and the whole flow and temperature fields in the S-CO_(2) cooling wall are revealed and discussed. A comparison study is made between the cooling wall tube and waterwall tube. Both temperature and thermal deformations of cooling wall tube are much higher than that of water. Numerical simulation results indicate that inclination angle has little effects on the temperature distribution, while increase of pressure drop is obvious as the inclination angle increases. Increasing tube diameter can effectively reduce both the pressure drop and the temperature of the cooling wall tube. As a result, a new insight is introduced for the design of S-CO_(2) power cycle.

关键词： supercritical CO_(2) cooling wall coal-fired power plant heat transfer

A New Structure of Cooling Wall Tube for Supercritical CO_(2)Coal-Fired Power Plants

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Journal of Thermal Science 2023年第3期32卷 1239-1250页

作者： WANG Yanjuan gao shuo JIANG Qiongqiong LI Yi LIU Qibin XU Jinliang The Beijing Key Laboratory of Multiphase Flow and Heat Transfer North China Electric Power UniversityBeijing 102206China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

In terms of developing supercritical CO_(2)(sCO_(2))coal-fired power plants,enhancing cooling wall performance is one of significant factors to improve system *** this paper,a new cooling wall tube structure is proposed to match the non-uniform heat flux(NUH)with the thermal resistance by changing the cooling wall tube eccentricity.A three-dimensional multi-physical coupling model of cooling wall is constructed to compare the novel structure to the conventional *** properties of fluid dynamics,thermal stress,coupled heat transfer and cooling wall deformation are *** contrast to the traditional structure,the maximum temperature and circumferential temperature difference(CTD)of the proposed structure can be reduced by 2%and 27.4%,*** essential working parameters related to the performances of the cooling wall tube are *** maximum temperature of the new structure is reduced by 8-13 K and the maximum thermal stress is reduced by about 10%-15%under all the simulated working conditions when the eccentricity changes from 0 to *** proposed structure can effectively reduce the maximum temperature and circumferential temperature gradient under ***,a novel insight is put out for the design and optimization of the cooling wall tube in coal-fired power plants.

关键词： supercritical carbon dioxide cooling wall tube thermal-hydraulic structural coupling supereritical heat transfer

Co-Catalyzed Dehydrogenation Claisen Condensation of Secondary Alcohols with Esters

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Chinese Journal of Chemistry 2024年第22期42卷 2818-2824页

作者： shuo gao Wentao Hao Yuqi Ji Xiulin Li Chunyan Zhang Guoying Zhang State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuanShanxi 030o01China College of Ecology Taiyuan University of TechnologyTaiyuanShanxi 030001China Universityof ChineseAcademyof Sciences Beijing100049China

Comprehensive Summary Catalytic dehydrogenation,with its exceptional atom economy and chemoselectivity,offers a highly desirable yet challenging approach for converting multiple environmentally friendly alcohols into crucial ***,the utilization of catalysts based on abundant elements found on Earth for alcohol dehydrogenation to produce acryl ketone holds significant promise as a versatile strategy in synthesizing key building blocks for numerous pharmaceutical *** present study describes a practical Co-catalyzed cascade dehydrogenative Claisen condensation of secondary alcohols with esters,facilitating the synthesis of a wide range of *** introduce a catalytic system based on novel and scalable indazole NNP-ligands coordinated to cobalt for efficient dehydrogenations of secondary alcohols,and propose a plausible reaction mechanism supported by control experiments and labeling ***,it allows for the streamlined synthesis of multiple pharmaceuticals in one-pot.

关键词： Cobalt Pincer Ligand Dehydrogenation Claisen Condensation 3-Hydroxy-prop-2-en-1-one Alcohols 3d transition metals Enols Enones

采用提篮钢板技术治疗粉碎性髌骨下极骨折的疗效分析

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骨科临床与研究杂志 2025年第1期10卷 26-31页

作者：齐巍高烁王一兵周力唐山市第二医院创伤一科 063000 首都医科大学附属北京积水潭医院创伤骨科 100035

目的探讨应用提篮钢板技术治疗粉碎性髌骨下极骨折的临床疗效。方法回顾性分析唐山市第二医院创伤一科2021年3月至2024年3月应用提篮钢板技术治疗的18例粉碎性髌骨下极骨折患者的临床资料,其中男10例,女8例,年龄21~73(44.1±14.2)岁;左... 详细信息

目的探讨应用提篮钢板技术治疗粉碎性髌骨下极骨折的临床疗效。方法回顾性分析唐山市第二医院创伤一科2021年3月至2024年3月应用提篮钢板技术治疗的18例粉碎性髌骨下极骨折患者的临床资料,其中男10例,女8例,年龄21~73(44.1±14.2)岁;左膝7例,右膝11例;交通伤8例,摔伤10例。应用提篮钢板技术治疗粉碎性髌骨下极骨折。住院期间观察记录患者年龄、性别、术前疼痛评分(FPS-R)。患者出院后于术后6周、8周、10周、12周、6个月、12个月门诊复查随访,记录骨折愈合时间、膝关节屈曲康复时间、末次随访FPS-R,末次随访B?stman髌骨骨折疗效评分。结果18例患者术前FPS-R评分6(4,6)分,切口均一期愈合,无失访患者;随访时间6~12个月;骨折愈合时间8(6,8.5)周;膝关节屈曲康复时间:90°需3(3,4)周,120°需6(6,8)周,全范围需10(8,10)周;末次随访FPS-R评分2(0,2)分;末次随访B?stman髌骨骨折疗效评分29(28,30)分,优17例,良1例,优良率为100%。18例患者骨折愈合良好,未出现感染、切口愈合不良、内固定物失效、内固定激惹等并发症。结论应用提篮钢板技术治疗粉碎性髌骨下极骨折疗效确切、满意。该技术可达到骨折坚强内固定、早期功能锻炼的目的,术后并发症少,骨折愈合率高,膝关节功能恢复好,疗效优良率高。该技术内固定材料获取容易,手术技术简单,适合在基层医院推广应用。

关键词：骨折固定术内骨固定钢丝髌骨下极骨折微型接骨板

Synthesis and Crystal Structure of 1D Cd-amine Coordination Polymer and Its Luminescent Properties

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Chemical Research in Chinese Universities 2014年第5期30卷 720-725页

作者： XU Mengying LIU Zhigang FAN Ruiqing gao Song CHEN shuo YANG Yulin Department of Chemistry Harbin Institute of Technology Harbin 150001 P. R. China

A novel one dimension（1D） cadmium coordination polymer {[Cd（mpda）3]·2（NO3）}n（1） was synthesized via refluxing a mixture of tetradentate Schiff base ligand N,N＇-bis（2-pyridinylethylidene）phenylene-1,3-diamine（L） and Cd（NO3）2 in acetonitrile, whose structure was characterized by means of single crystal X-ray diffraction, FTIR spectroscopy, elemental analysis and proton nuclear magnetic resonance（1H NMR）. Center metal Cd（II） ion is six-coordinated by six nitrogen atoms from six different m-phenylenediamine（mpda）, giving rise to a [CdN6] octahe- dral coordination environment. The two adjacent cadmium centers are linked by three mpda molecules leading to the construction of 1D chain structure. The crystal structure is stabilized by N-H…O hydrogen bonds to form three-dimension supramolecule. Compound 1 exhibits intense yellow luminescence in solid state at 298 K（λem=554 nm）, which shows a blue shift at 77 K（ca. 147 nm）. Additionally, fluorescence characteristics of compound 1 were investigated in different solvents（polarity： DMSO〉CH3CN〉CH3OH〉CHC13〉toluene） at 298 and 77 K. The results show that the emission peak of compound 1 in solvent exhibits a slight bathochromic shift. However, the emission peaks of compound 1 in CH3OH and CHC13 are red shift compared with that in CH3CN. It is revealed that the lumi- nescence behavior of compound 1 depends on not only the polarity of solvent but also the hydrogen bonding proper- ties between solvent and solute. In addition, the emission peak of compound 1 in solution shows a red shift obviously at 77 K than that at 298 K（ca. 144-159 nm）, with the fluorescence lifetime increased at 77 K. The lifetime in DMSO at 77 K（r=12.470μs） was the longest one. The quantum yield of compoud 1 increases with increasing the polarity of solvent within a range of 1.8%-8.3 %.

关键词： Schiffbase Cd(II)-amine compound Luminescence Crystal structure

Enhanced electrocatalytic CO_(2)reduction to formic acid using nanocomposites of In_(2)O_(3)@C with graphene

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Nano Research 2024年第6期17卷 5031-5039页

作者： Wenxiang Li shuo gao Chuanruo Yang Juntao Yang Amjad Nisar Guolei Xiang Junsu Jin Beijing Key Laboratory of Membrane Science and Technology Beijing University of Chemical TechnologyBeijing 100029China Nanomaterials Research Group PDPINSTECHIslamabad 44000Pakistan Institute of Industrial Chemistry College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China

In_(2)O_(3)is an effective electrocatalyst to convert CO_(2)to formic acid(HCOOH),but its inherent poor electrical conductivity limits the efficient charge transfer during the ***,the tendency of In_(2)O_(3)particles to agglomerate during synthesis further limits the exposure of active *** we address these issues by leveraging the template effect of graphene oxide and employing InBDC as a self-sacrificing template for the pyrolysis synthesis of In_(2)O_(3)@*** resulting In_(2)O_(3)@C/rGO-600 material features In_(2)O_(3)@C nanocubes uniformly anchored on a support of reduced graphene oxide(rGO),significantly enhancing the active sites *** conductive rGO network facilitates charge transfer during electrocatalysis,and the presence of oxygen vacancies generated during pyrolysis,combined with the strong electron-donating ability of rGO,enhances the adsorption and activation of CO_(2).In performance evaluation,In_(2)O_(3)@C/rGO-600 exhibits a remarkable HCOOH Faradaic efficiency exceeding 94.0%over a broad potential window of−0.7 to−1.0 V(*** hydrogen electrode(RHE)),with the highest value of 97.9%at−0.9 V(***)in a ***,the material demonstrates an excellent cathodic energy efficiency of 71.6%at−0.7 V(***).The study underscores the efficacy of uniformly anchoring metal oxide nanoparticles onto rGO for enhancing the electrocatalytic CO_(2)reduction performance of materials.

关键词： In_(2)O_(3)@C nanocomposite electrochemical CO_(2)reduction reduced graphene oxide oxygen vacancy

Piezoelectric-Based Smart Bone Plate for Fracture Healing Progress Monitoring

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Journal of Shanghai Jiaotong university(Science) 2022年第4期27卷 561-569页

作者： gao Zihang WANG Xin ZHAO Yifana JIN Zhehuia WANG Gang gao shuo School of Instrumentation Science and Optoelectronic Engineering Beihang UniversityBeijing100083China Beijing Advanced Innovation Center for Big Data-Based Precision Medicine Interdisciplinary Innovation Institute of Medicine and EngineeringBeihang UniversityBeijing100083China

Fracture healing progress monitoring techniques attract global research attention due to the importance of selecting the timing of removing the fixation *** this end,in this research,we present a piezoelectric-based smart internal fixation device,in which a piezoelectric sandwich structure is laminated to the surface of a bone *** the content,we explain the reasons for utilizing piezoelectric films,elaborate the mechanism of fracture monitoring,and introduce the mechanical parameters of the *** simulation and experimental results show that the electrical output of the device is associated with the elastic modulus of the filler between the tested broken bones when the working load is maintained,indicating that the bone recovery progress could be successfully detected by the developed technique.

关键词： piezoelectric device bone plate fracture healing monitoring Internet of Health Things

Effect of Zr on solidification and microstructure of a Ni-based superalloy with high Al and Ti contents

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China Foundry 2022年第1期19卷 17-26页

作者： Guang-di Zhao Xi-min Zang Fang Liu Wei-wei Zhang shuo gao Xue Li Jing Guo School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The total content of Al and Ti in advanced Ni-based wrought superalloys is up to 7.5wt.%,which makes it easier to form harmful nonequilibrium eutectic(γ+γ′)andη*** has been reported that the addition of certain amount of Zr can modify precipitation of the nonequilibrium phases obviously,but the mechanism is still *** effect of Zr ranging from<0.0006wt.%to 0.150wt.%on solidification behavior,segregation and microstructure of a Ni-based superalloy with high Al and Ti contents was investigated,eliminating the interferences of C and *** show that increase in Zr content significantly promotes the formation of eutectic(γ+γ′),ηand Zr-rich phase in the interdendritic *** the Zr-rich phase,Zr dissolves slightly in the eutecticγ′and obviously in theη*** interesting phenomenon is discovered that the Zr addition significantly increases the area fraction of liquid pools and enlarges the forming range ofγdendrites,which suggests that Zr markedly retards the *** affects the eutectic(γ+γ′)andηformation mainly due to the retard of solidification and dissolution of Zr in *** retard of solidification obviously increases the residual liquid fraction and *** can serve as a forming element for the eutectic(γ+γ′)andηphase,and the obvious dissolution of Zr inηphase significantly decreases the critical concentration of Ti for its precipitation.

关键词： zirconium Ni-based superalloy solidification behavior segregation