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Numerical and experimental evaluation for density-related thermal insulation capability of entangled porous metallic wire material

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Defence Technology（防务技术） 2023年第5期23卷 177-188页

作者： Tao Zhou Rong-zheng Fang Di Jia pei Yang Zhi-ying Ren Hong-bai bai 92578 Troops of the Chinese People's Liberation Army Beijing100055PR China School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou350116PR China Institute of Metal Rubber&Vibration Noise Fuzhou UniversityFujianFuzhou350116PR China

Entangled porous metallic wire material(EPMWM)has the potential as a thermal insulation material in defence and *** order to optimize its thermophysical properties at the design stage,it is of great significance to reveal the thermal response mechanism of EPMWM based on its complex structural *** the present work,virtual manufacturing technology(VMT)was developed to restore the physics-based 3D model of *** this basis,the transient thermal analysis is carried out to explore the contact-relevant thermal behavior of EPMWM,and then the spiral unit containing unique structural information are further extracted and *** particular,the thermal resistance network is numerically constructed based on the spiral unit through the thermoelectric analogy method to accurately predict the effective thermal conductivity(ETC)of ***,the thermal diffusivity and specific heat of the samples were obtained by the laser thermal analyzer to calculate the ETC and thermal insulation factor of *** results show that the ETC of EPMWM increases with increasing temperature or reducing density under the experimental *** numerical prediction is consistent with the experimental result and the average error is less than 4%.

关键词： Entangled porous metallic wire material (EPMWM) Virtual manufacturing technology(VMT) Thermal resistance network Effective thermal conductivity(ETC) Thermal insulation factor

Patterned surfaces for biological applications:A new platform using two dimensional structures as biomaterials

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Chinese Chemical Letters 2017年第4期28卷 675-690页

作者： wen-Dong Liu bai Yang State Key Laboratory of Supramolecular Structure and Materials International Joint Research Laboratory of Nano-Micro Architecture ChemistryCollege of ChemistryJilin UniversityChangchun 130012China

With the highly interdisciplinary of research and great development of microfabrication techniques,patterned surfaces have attracted great attention of researchers since they possess specific regularity and orderness of *** recent years,series of two dimensional patterned structures have been successfully fabricated,and widely used in anti-reflection,anti-fogging,self-cleaning,and sensing,*** the meantime,patterned structures have been gradually used in biologically relative fields such as biomaterials,aiming to deepen the perception of organism and understand the vital movements of human *** this review,we provide a brief introduction on current status of techniques for two dimensional patterns fabrication,the applications of patterned surfaces in biologically related fields,and give out a prospective on the development of these patterned surfaces in the future.

关键词： Pattern Microfabrication Sensing Adhesion Biomolecule Biomedical

Applying sub-band energy extraction to noise cancellation of ultrasonic NDT signal

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1134-1140页

作者： Qi ZHANG pei-wen QUE Wei LIANG Institute of Automation Detection Shanghai Jiao Tong University Shanghai 200240 China

In ultrasonic non-destructive tests, the echo signal at the flaw is highly complex due to the interference of multiple echoes with random amplitudes and phases, and is disturbed by all kinds of noises, such as thermal noise, digitalization noise, and structure noise. In this paper, the ultrasonic signal was decomposed by empirical mode decomposition (EMD) to obtain the in-trinsic mode function (IMF) components according to ultrasonic defect echo signals occuring at the corresponding time, and the energy of the ultrasonic signal was concentrated. The IMF component selection criterion based on sub-band energy extraction was proposed to extract the ultrasonic signal component accurately and automatically from IMF components. When the selected IMF components were filtered by a band pass filter, the signal-to-noise ratio (SNR) was enhanced greatly.

关键词： Empirical mode decomposition (EMD) Signal-to-noise ratio (SNR) De-noising Non-destructive testing (NDT) Intrinsic mode function (IMF)

Prenatal ultrasonography and genetic analysis of fetal cleidocranial dysplasia:A case report

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World Journal of Clinical Cases 2025年第10期13卷 28-34页

作者： Feng Wang pei-Feng Dai wen-Juan Gao Department of Ultrasonography Weifang People’s HospitalWeifang 261000Shandong ProvinceChina

BACKGROUND Cleidocranial dysplasia(CCD)is an infrequent clinical condition with an autosomal dominant inheritance *** is characterized by abnormal clavicles,patent sutures and fontanelles,supernumerary teeth,and short *** 60%-70%of patients with CCD have mutations in the RUNX family transcription factor 2 ***,prenatal diagnosis of CCD is difficult when the family history is *** SUMMARY We report a rare case of fetal CCD with an unknown family history,confirmed by prenatal ultrasonography and genetic testing at a gestational age of 16 *** genetic reports indicated that the fetus carried pathogenic mutations in the RUNX family transcription factor 2 gene(c.674G>A).After careful consideration,the pregnant woman and her family decided to continue the *** Definitive prenatal diagnosis of CCD should include family history,ultrasound diagnosis,and genetic analysis,especially if family history is unknown.

关键词： Cleidocranial dysplasia Genetic analysis Ultrasonic diagnosis Prenatal Case report

Finite-time Adaptive Fault-tolerant Control for Nonlinear Systems With Multiple Faults

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IEEE/CAA Journal of Automatica Sinica 2019年第6期6卷 1417-1427页

作者： Huanqing Wang wen bai Peter Xiaoping Liu School of Mathematics Bohai UniversityJinzhou 121000China Department of Systems and Computer Engineering Carleton UniversityOttawaON K1S 5B6Canada

This paper focuses on the problem of adaptive finitetime fault-tolerant control for a class of non-lower-triangular nonlinear *** faults encountered in the control system include the actuator faults and the abrupt system *** applying backstepping design and neural networks approximation,an adaptive finite-time fault-tolerant control scheme is *** is shown that the proposed controller ensures that all signals in the closed-loop system are semi-globally practically finite-time stable and the track-ing error converges to a small neighborhood around the origin within finite *** simulation is carried out to explain the validity of the developed strategy.

关键词： Adaptive control backstepping faults finite time

Modification of ash flow properties of coal rich in calcium and iron by coal gangue addition

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Chinese Journal of Chemical Engineering 2021年第7期34卷 239-246页

作者： Huaizhu Li Lingxue Kong Jin bai Zongqing bai Zhenxing Guo wen Li Key Laboratory of Coal Processing and Efficient Utilization Ministry of EducationXuzhou 221116China State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China

Flow property of coal ash and slag is an important parameter for slag tapping of entrained flow *** viscosity of slag with high contents of calcium and iron exhibits the behavior of a crystalline slag,of which viscosity sharply increases when temperature is lowered than temperature of critical viscosity(TCV).The fluctuation in temperature near the TCVcan cause an accumulation of slag inside the *** order to prevent slag blockage,it is necessary to adjust the ash composition by additive to modify the flow property of coal rich in calcium and *** components of coal gangue are Al_(2)O_(3) and SiO_(2),which is a potential additive to modify the ash flow properties of these *** this work,we investigated the ash flow properties of a typical coal rich in calcium and iron by adding coal gangue with different SiO_(2)/Al_(2)O_(3)*** results showed that the ash fusion temperatures(AFTs)firstly decreased,and then increased with increasing amount of coal gangue *** composition of coal ash rich in calcium and iron moved from gehlenite primary phase to anorthite,quartz and corundum primary *** slags with coal gangue addition behaved as a glassy slag,of which the viscosity gradually increased as temperature ***,a high SiO_(2)/Al_(2)O_(3)ratio of coal gangue was beneficial to modify the slag viscosity *** of coal gangue with a high SiO_(2)/Al_(2)O_(3)ratio impeded formation of crystalline phases during *** work demonstrated that coal gangue addition was an effective way to improve the ash flow properties of the coal rich in calcium and iron for the entrained flow gasifier.

关键词： Coal gangue Coal rich in calcium and iron Ash fusion temperatures Viscosity-temperature characteristic Phase transformation

D301 resin as a solid base for phosphine-free Heck reactions with heteroaryl halides

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Chinese Chemical Letters 2008年第4期19卷 399-402页

作者： wen pei Xiang Mei Wu College of Chemical Engineering and Materials Zhejiang University of TechnologyHangzhou 310014China College of Chemistry and Life Science Lishui UniversityLishui 323000China

A new and practical method of the D301 resin,a weak basic anion exchange resin with secondary amine functionality（Grade Matrix Structure：Styrene-DVB D301R）,used as base to Heck reactions catalyzed by palladium reagent without phosphine compound as ligand is *** was found that the D301 resin used as base is an efficient and reusable base and can be regenerated and recycled in the *** olefmation of heteroaryl halides prepared the corresponding products in good yields using D301 resin as base.

关键词： Hock reaction Palladium Phosphine-free catalysts D301 resin

利用电子病案资源促进妇产科学以问题为基础学习教学效果的探索

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中华医学教育杂志 2008年第5期28卷 66-67,90页

作者：白文佩焦建军廖秦平温宏武赵丽丽郝瀚李颖3 唐亮芳北京大学第一医院妇产科 100034 北京大学第一医院病案室 100034 北京大学医学部八年制临床医学专业2002级学生

病例讨论是以问题为基础学习（problem—based learning，PBL）教学模式的主要组成部分。根据教学对象和教学进度，选择合适的病例是达到良好教学目的的必要前提和保障。在临床医学工作中注意搜集、整理病案资源，经过电子化处理，可以... 详细信息

病例讨论是以问题为基础学习（problem—based learning，PBL）教学模式的主要组成部分。根据教学对象和教学进度，选择合适的病例是达到良好教学目的的必要前提和保障。在临床医学工作中注意搜集、整理病案资源，经过电子化处理，可以制作成为易于检索、易于阅读、资料完整、病种齐全的电子病案数据库。北京大学第一医院妇产科学教研室在教学中使用电子病案资源，体会到其教学资料丰富、齐全，获取资料快捷、方便的特点，提高了学生自主学习的浓厚兴趣；经过提炼之后，可以成为医学教育的共享资源。

关键词：电子病案妇产科学以问题为基础学习

Experimental study on calculation model of labyrinth emitter discharge under subsurface drip irrigation

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International Journal of Agricultural and Biological Engineering 2014年第6期7卷 14-19页

作者： Hou wen bai Dan Zhou wen Institute of Water Resources and Hydroelectric Engineering Xi'an University of TechnologyXi'an 710048China College of Conservancy North China University of Water Resources and Electric PowerZhengzhou 450011China

For different texture of soils,the grain composition is different with significant *** the emitter of subsurface drip irrigation(SDI)is buried in the soil,emitter discharge is influenced by soil *** experiment was conducted to investigate the relationship between the soil properties with emitter working pressure and emitter discharge of *** three different grain composition soils,and emitter working pressure,as well as soil clay content,soil bulk density and initial soil moisture content respectively as influence factors of emitter discharge of SDI,the experimental scheme was gained by uniform design.A calculation model for determination of the SDI emitter discharge was established by regression analysis with the first two kinds of soil test data,and its reliability was verified by the third kind of soil test *** model is simple with high accuracy,easy to use,and lays the foundation to study hydraulic elements of SDI field network,especially taking the soil clay content as an influencing factor has widened the scope of application of the *** achievement is of great significance for design and management of SDI.

关键词： subsurface drip irrigation emitter soil clay content discharge calculation model