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Mechanical Properties Study of Reinforced Thermoplastic Pipes Under A Tensile Load

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China Ocean Engineering 2020年第6期34卷 806-816页

作者： wang yang-yang LOU Min TONG Bing wang Sen School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao 266580China Hoisting Machinery Business Division Xuzhou Construction Machinery Group(XCMG)Xuzhou 221000China Weihai Nacheon Pipeline Co. Ltd.Weihai 264400China

This paper presents a study on the tensile properties of reinforced thermoplastic pipes(RTPs). A mechanical model of RTPs with an arbitrary number of reinforced layers under tensile action is constructed by combining the constitutive relationship of elastoplastic materials with the continuous displacement condition. On this basis, the effects of various parameters such as the winding angle, the number of structurally reinforced layers, and the inner polyethylene(PE) liner thickness on the tensile properties of the RTPs were analyzed, and a tensile test was carried out for validation. The results showed that the winding angle of the structurally reinforced layers was the main factor affecting an RTP's tensile performance— decreases in the winding angle significantly improved its tensile ability,especially the longitudinal strength. With ±45° as the demarcation point, the winding angle smaller than ±45° will result in higher strength in longitudinal direction, and the lifting effect on RTP's mechanical properties of the increasing number of reinforcement layers was better than that of the increasing thickness of the lining layer;when the winding angle was larger than ±45°, the opposite results were obtained. The fibre load was more sensitive to the winding angle than the PE load.

关键词： reinforced thermoplastic pipes tensile properties winding angle polyethylene

Heat Transfer Effectiveness of Three-Fluid Separated Heat Pipe Exchanger

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Journal of Thermal Science 2011年第1期20卷 64-69页

作者： Chengming Shi yang wang Ying yang Quan Liao College of Power Engineering Chongqing University Chongqing 400044 China

A heat transfer model for three-fluid separated heat pipe exchanger was analyzed,and the temperature transfer matrix for general three-fluid separated heat exchanger working in parallel-flow or counter-flow mode was *** was found that the forms of temperature transfer matrix are similar for heat pipe rows with equal or different heat transfer surface ***,by using the temperature transfer matrix of the heat pipe exchanger,the relationship between heat transfer effectiveness θ 1,θ 2 and M,NTU,U,Δt i were derived for the exchanger operating in parallel-flow or counter-flow mode,and a simple special example was adopted to demonstrate the correctness of these relationships.

关键词： heat pipes three-fluid heat exchangers heat transfer effectiveness temperature transfer matrix

Autonomous Path Planning For Robot Manipulators in Manufacturing Environment

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International Journal of Minerals,Metallurgy and Materials 1998年第2期12卷 104-107页

作者： Wei wang yang yang Kui Yuan Information Engineering School, UST Beijing, Beijing 100083, China Information Engineering School UST Beijing Beijing 100083 China

A robot intelligent path planning system(RIPPS), which can be used as a robot off-line programming tool was introduced in this paper. C-space modeling and path search are key parts of the system. A fast C-space modeling is presented based on critical collision joint angle(CCJA), C-obstacle boundary can be computed by the feature points of obstacles. A modified A* algorithm is used for path search, although the path is slightly sub-optimal, a tremendous speed increase is achieved. RIPPS runs on a Silicon Graphic 4D/70 workstation, simulation results show that the system is efficient and practical for robot collision-free autonomous path planning in a structured and known environment.

关键词： robot path plalanning A~* algorithm

Arabidopsis Galacturonosyltransferase （GAUT） 13 and GAUT14 Have Redundant Functions in Pollen Tube Growth

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Molecular Plant 2013年第4期6卷 1131-1148页

作者： Li wang Wei wang You-Qun wang yang-yang Liu Jing-Xin wang Xue-Qin Zhang De Ye Li-Qun Chen State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University Beijing 100193 China

Cell wall biosynthesis is indispensable for pollen tube growth. Despite its importance to sexual reproduction, the molecular mechanisms of pollen tube wall biosynthesis remain poorly understood. Here, we report functional characterization of two putative Arabidopsis galacturonosyltransferase genes, GAUT13 and GAUT14, which are essential for pollen tube growth. GAUT13 and GAUT14 encode the proteins that share a high amino acid sequence identity and are located in the Golgi apparatus. The T-DNA insertion mutants, gaut13 and gaut14, did not exhibit any observable defects, but the gaut13 gaut14 double mutants were defective in pollen tube growth; 35.2-37.3% pollen tubes in the heterozygous double mutants were swollen and defective in elongation. The outer layer of the cell wall did not appear distinctly fibrillar in the double mutant pollen tubes. Furthermore, distribution of homogalacturonan labeled with JIM5 and JIM7 in the double mutant pollen tube wall was significantly altered compared to wild-type. Our results suggest that GAUT13 and GAUT14 function redundantly in pollen tube growth, possibly through participation in pectin biosynthesis of the pollen tube wall.

关键词： Arabidopsis cell wall GAUT13 GAUT14 pectin pollen tube.

分子印迹技术在牛奶中四环素类残留检测中的应用研究进展

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食品安全质量检测学报 2025年第4期16卷 215-223页

作者：商健苏新科乔帅王杨阳李建文渭南市检验检测研究院渭南714000

四环素类抗生素在畜牧业中广泛应用,其进入牛奶的主要途径为环境带入和奶牛直接摄取,而四环素类经食物链积累毒性,会威胁人类健康。分子印迹技术可定制与四环素类特异性结合的高分子网络聚合物,具有诸多优势,如选择性高、机械性能良好... 详细信息

四环素类抗生素在畜牧业中广泛应用,其进入牛奶的主要途径为环境带入和奶牛直接摄取,而四环素类经食物链积累毒性,会威胁人类健康。分子印迹技术可定制与四环素类特异性结合的高分子网络聚合物,具有诸多优势,如选择性高、机械性能良好、成本低、耐高温和酸碱、可重复使用等,在牛奶中四环素类残留检测中发挥重要作用。分子印迹结合固相萃取技术能简化前处理过程、优化方法,有效解决牛奶基质复杂带来的分离纯化难题,具体包括固相萃取、固相微萃取、分散固相萃取、磁固相萃取等4种固相萃取与色谱联用技术;基于分子印迹技术的特异性识别能力与传感器(涵盖分子印迹电化学、荧光、光子晶体、等离子体共振、光电传感器这5类传感器)联用能提高选择性、稳定性及响应速度等,操作简单,尤其适用于现场快速筛查。本文分别介绍了上述技术和传感器在牛奶中四环素类残留检测的研究进展,分析讨论其应用效果,并指出未来分子印迹技术在该领域的努力方向,为后续研发及应用提供参考。

关键词：分子印迹技术牛奶四环素类

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Engineering strategies of biomaterial-assisted exosomes for skin wound repair:Latest advances and challenges

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Chinese Chemical Letters 2025年第1期36卷 99-109页

作者： yang Xu Le Ma yang wang Chunmeng Shi Institute of Rocket Force Medicine State Key Laboratory of Trauma and Chemical PoisoningThird Military Medical University(Army Medical University)Chongqing 400038China

The treatment of skin wounds,especially chronic wounds,remains a critical clinical challenge and places a heavy burden on patients and healthcare *** recent years,the engineering strategy of using biomaterial-assisted exosomes has emerged as a powerful tool for skin *** to treatments such as debridement and regular dressing changes,the design of biomaterial-assisted exosomes not only maintains the bioactivity of exosomes at the wound site but also provides an appropriate microenvironment for the repair of complex tissues,thereby accelerating wound *** review systematically introduces the general characteristics of exosomes and their functions in skin wound healing,highlights recent advances in classification of natural exosomes and engineering methods which enriching their functions in intercellular ***,various emerging and innovative approaches based on biomaterials delivery of exosomes are comprehensively *** review seeks to bring an in-depth understanding of bioactive dressings based on exosomes therapeutic strategies,aiming to facilitate new clinical application value.

关键词： Exosomes Biomaterials Hydrogel Delivery system Wound healing

Effects of femtosecond laser ablation on the surface morphology and microstructure of a bulk TiCuPdZr glass alloy

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Rare Metals 2009年第3期28卷 272-276页

作者： wang Hongshui LIANG Chunyong CHEN Xueguang wang Lei yang yang yang Jianjun ZHU Shengli LI Changyi School of Materials Science and Engineering Hebei University of Technology Tianjin 300130 China Key Laboratory of the Ministry of Education of China for Opto-electronic Information Science and Technology Institute of Modem Optics Nankai University Tianjin 300071 China School of Materials Science and Engineering Tianjin University Tianjin 300072 China Stomatological Hospital Tianjin Medical University Tianjin 300070 China

The effects of femtosecond laser ablation on the surface characteristics and microstructure of a bulk TiCuPdZr glass alloy were investigated. The heat influence zone of femtosecond laser ablated with a laser energy of 100 μJ exhibits a ripple-like feather, while a porous structure appears on the surface of the specimen ablated by a 200 μJ femtosecond laser. The contents of Ti, Zr, and Pd on the ablated surface decrease and that of Cu increases with increasing laser energy. The crystallization process occurs on the glass alloy specimens during femtosecond laser ablation, and the crystallinity of a 100 μJ femtosecond laser-ablated specimen is greater than that of a 200 μJ femtosecond laser-ablated one.

关键词： femtosecond laser bulk glass alloy periodicity crystallization

Mechanism of calcium mitigating membrane fouling in submerged membrane bioreactors

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Journal of Environmental Sciences 2009年第8期21卷 1066-1073页

作者： ZHANG Hanmin, XIA Jie, yang yang, wang Zixing, yang FenglinKey Laboratory of Industrial Ecology and Environmental Engineering, MOE, School of Environmental and Biological Science and Technology, Dalian University of Technology, Dalian 116024, China. [a]Key Laboratory of Industrial Ecology and Environmental Engineering MOE School of Environmental and Biological Science and Technology Dalian University of Technology Dalian 116024 China

Two parallel membrane bioreactors （MBRs） were operated under different calcium dosages （168.5, 27 mg/L） to gain a better understanding of the mechanism of retarding membrane fouling by adding calcium. The results showed that the particle size of sludge flocs increased and the particle size distribution tended to be narrow at the optimum dosage （168.5 mg/L）. Calcium was effective in decreasing loosely bound extracellular polymeric substances （LB-EPS） in microbial flocs and soluble microbial products （SMP） in the supernatant at the dosage of 168.5 mg/L by strengthening the neutralization and bridging of EPS with flocs. Furthermore, the amount of CODs and CODc decreased in both the mixed liquor and the fouling cake layer on the membrane surface. In order to compare the filtration characteristics of cake layers from the MBRs with the two calcium dosages, the specific cake resistance and the compressibility coefficient were measured. The specific cake resistance from the MBR with optimum dosage （168.5 mg/L） was distinctly lower than that with low dosage （27 mg/L）. The compressibility coefficient of the cake layers under two dosages were respectively attained as 0.65, 0.91. Scanning electron microscopy （SEM） and three-dimensional confocal scanning laser microscope analysis （CLSM） images were utilized to observe the gel layer directly.

关键词： calcium membrane fouling loosely bound extracellular polymeric substances (LB-EPS) compressibility coefficient

Reconstructing forest and grassland cover changes in China over the past millennium

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Science China Earth Sciences 2025年第1期68卷 94-110页

作者： Fanneng HE Fan yang Yafei wang Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China Key Research Institute of Yellow River Civilization and Sustainable Development Henan UniversityKaifeng475001China University of Chinese Academy of Sciences Beijing100049China

Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations and terrestrial ecosystem carbon emission ***,because of limitations in historical data,quantitative estimations and spatially gridded reconstructions of these changes remain challenging,necessitating further methodological *** study focused on China's present-day land area over the past millennium,objectively capturing the characteristics and drivers of forest and grassland cover *** this basis,using the forest transition theory and the space-for-time substitution method,we depicted the historical deforestation process as an inverted“S”curve and developed a model to reconstruct historical forest area changes based on the functional relationship between the forest area and population size ***,a gridded forest allocation model was established on the basis of deforestation *** the grassland cover,we implemented regionspecific methods,such as the cropland area deduction method and the habitat constraint method,to quantitatively reconstruct historical ***,we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland *** results indicated the following.(1)The methods developed using population data as a proxy objectively reproduced the spatiotemporal evolution of forest and grassland cover in China over the past *** feasible methods offer a novel pathway for the quantitative reconstruction of historical forest and grassland cover changes.(2)The data indicated that China's forest area generally decreased over the past millennium,characterized by a“decrease-then-increase”*** forest area experienced three distinct phases:a slow decline(AD 1000–1650),a rapid decline(AD 16

关键词： Land use and land cover change Forest Grassland Quantitative reconstruction Gridded reconstruction China historical period