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原状海砂对混凝土力学性能的影响

硅酸盐通报 2024年第6期43卷 2149-2156页

作者：郑建岚王雅思叶艳福建江夏学院工程学院福州350108 福建省环保节能型高性能混凝土协同创新中心福州350108 福州大学土木工程学院福州350108

为探究高氯盐、高贝壳含量原状海砂混凝土的力学性能,以海砂的氯离子含量和贝壳含量为变量,设计并配制9组海砂混凝土,开展混凝土立方体抗压强度试验和单轴受压应力-应变全曲线试验。结果表明:随着氯离子含量增加,混凝土的孔结构细化,早... 详细信息

为探究高氯盐、高贝壳含量原状海砂混凝土的力学性能,以海砂的氯离子含量和贝壳含量为变量,设计并配制9组海砂混凝土,开展混凝土立方体抗压强度试验和单轴受压应力-应变全曲线试验。结果表明:随着氯离子含量增加,混凝土的孔结构细化,早期强度提高,单轴受压应力-应变全曲线峰值应力增大,峰值应变降低,弹性模量提高;随着贝壳含量增加,混凝土坍落度显著下降,混凝土的孔结构较疏松,强度降低,单轴受压应力-应变全曲线峰值应力降低,峰值应变增大,弹性模量降低。在现有模型基础上,提出关于氯离子含量、贝壳含量的模型参数计算式。

关键词：海砂混凝土原状海砂单轴受压应力-应变全曲线氯离子含量贝壳含量

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An improved method for edge detection based on neighbor distance for processing hemispheric photography

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Journal of Plant Ecology 2024年第2期17卷 134-145页

作者： yasi Liu Dayong Fan Han Sun Xiangping wang State Key Laboratory of Effcient Production of Forest Resources School of Ecology and Nature ConservationBeijing Forestry UniversityBeijing 100083China The Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing 100083China

Hemisphere photos are now widely applied to provide information about solar radiation dynamics,canopy structure and their contribution to biophysical processes,plant productivity and ecosystem *** present study aims to improve the original‘edge detection’method for binary classifcation between sky and canopy,which works not well for closed *** supposed such inaccuracy probably is due to the infuence of sky pixels on their neighbor canopy ***,we introduced a new term‘neighbor distance’,defned as the distance between pixels participated in the calculation of contrast at the edges between classifed canopy and sky,into the‘edge detection’*** showed that choosing a suitable neighbor distance for a photo with a specifc gap fraction can signifcantly improve the accuracy of the original‘edge detection’*** developed an ND-IS(Neighbor Distance-Iteration Selection)method that can automatically determine the threshold values of hemisphere photos with high accuracy and *** combines the modifed‘edge detection’method and an iterative selection method,with the aid of an empirical power function for the relationship between neighbor distance and manually verifed gap *** procedure worked well throughout a broad range of gap fractions(0.019-0.945)with different canopy compositions and structures,in fve forest biomes along a broad gradient of latitude and longitude across Eastern *** results highlight the necessity of integrating neighbor distance into the original‘edge detection’*** advantages and limitations of the method,and the application of the method in the feld were also discussed.

关键词： hemisphere photos ‘edge detection’method neighbor distance gap fraction forest

The fabrication,characterization and functionalization in molecular electronics

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International Journal of Extreme Manufacturing 2022年第2期4卷 49-91页

作者： Yi Zhao Wenqing Liu Jiaoyang Zhao yasi wang Jueting Zheng Junyang Liu Wenjing Hong Zhong-Qun Tian State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005People’s Republic of China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005People’s Republic of China

Developments in advanced manufacturing have promoted the miniaturization of semiconductor electronic devices to a near-atomic scale,which continuously follows the‘top-down’construction ***,huge challenges have been encountered with the exponentially increased cost and inevitably prominent quantum *** electronics is a highly interdisciplinary subject that studies the quantum behavior of electrons tunneling in *** aims to assemble electronic devices in a‘bottom-up’manner on this scale through a single molecule,thereby shedding light on the future design of logic circuits with new operating *** core technologies in this field are based on the rapid development of precise fabrication at a molecular scale,regulation at a quantum scale,and related applications of the basic electronic component of the‘electrode-molecule-electrode junction’.Therefore,the quantum charge transport properties of the molecule can be controlled to pave the way for the bottom-up construction of single-molecule *** review firstly focuses on the collection and classification of the construction methods for molecular ***,various characterization and regulation methods for molecular junctions are discussed,followed by the properties based on tunneling theory at the quantum scale of the corresponding molecular electronic ***,a summary and perspective are given to discuss further challenges and opportunities for the future design of electronic devices.

关键词： molecular electronics molecular junction molecular electronic device fabrication and functionalization

3D-Integrated metasurfaces for full-colour holography

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Light(Science & Applications) 2019年第1期8卷 400-408页

作者： Yueqiang Hu Xuhao Luo Yiqin Chen Qing Liu Xin Li yasi wang Na Liu Huigao Duan State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan University410082 ChangshaPeople’s Republic of China Kirchhoff Institute for Physics University of HeidelbergIm Neuenheimer Feld 22769120 HeidelbergGermany

Metasurfaces enable the design of optical elements by engineering the wavefront of light at the subwavelength *** to their ultrathin and compact characteristics,metasurfaces possess great potential to integrate multiple functions in optoelectronic systems for optical device ***,current research based on multiplexing in the 2D plane has not fully utilised the capabilities of metasurfaces for multi-tasking ***,we demonstrate a 3D-integrated metasurface device by stacking a hologram metasurface on a monolithic Fabry–Pérot cavity-based colour filter microarray to simultaneously achieve low-crosstalk,polarisation-independent,high-efficiency,full-colour holography,and *** dual functions of the device outline a novel scheme for data recording,security encryption,colour displays,and information *** 3D integration concept can be extended to achieve multi-tasking flat optical systems by including a variety of functional metasurface layers,such as polarizers,metalenses,and others.

关键词： surfaces recording integrate

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再生骨料强化方法研究进展

材料导报 2021年第5期35卷 5053-5061页

作者：王雅思郑建岚游帆福州大学土木工程学院福州350108 福建江夏学院工程学院福州350108 福建省环保节能型高性能混凝土协同创新中心福州350108

再生骨料混凝土作为新型环保材料,满足节约资源和能源、减少环境污染以及可持续发展战略的要求,是绿色混凝土的主要研究方向和推广方向。再生骨料表面附着老水泥砂浆,表面粗糙、棱角多,并含有大量孔洞以及二次破碎过程产生的微裂纹,与... 详细信息

再生骨料混凝土作为新型环保材料,满足节约资源和能源、减少环境污染以及可持续发展战略的要求,是绿色混凝土的主要研究方向和推广方向。再生骨料表面附着老水泥砂浆,表面粗糙、棱角多,并含有大量孔洞以及二次破碎过程产生的微裂纹,与天然骨料相比,再生骨料存在密度低、吸水率大、压碎指标大、坚固性差、离散性大等不足,且再生骨料与其表面附着砂浆间存在薄弱界面区,使再生骨料混凝土的性能受到影响、工程应用受到限制。因此,提高再生骨料性能是再生骨料混凝土研究中的关键问题之一。传统提高再生骨料混凝土性能的方法主要聚焦在混凝土拌和阶段,通过改善拌和方法、加入矿物掺合料、优化混凝土配合比设计,或通过优化再生骨料级配、降低再生骨料取代率,以弱化再生骨料对再生骨料混凝土性能的不利影响,但本质上并未改善再生骨料的缺陷。而对再生骨料进行强化处理可改善再生骨料的性能。现有再生骨料强化方法主要从再生骨料表面附着砂浆着手,通过物理、化学或生物方法去除老砂浆或增强老砂浆来提高再生骨料的性能,如机械研磨、火山灰质浆液浸泡、纳米材料改性、二氧化碳强化法等。此外,通过骨料重组法对再生骨料成分进行分类、重组,也可在一定程度上提高再生骨料性能,进而达到改善再生骨料混凝土性能的目的。本文总结了国内外已有再生骨料强化方法的研究进展,分别介绍了去除老砂浆、增强老砂浆、骨料重组三类再生骨料强化方法及其作用机理,总结分析了再生骨料强化方法的强化效果,提出进一步研究再生骨料强化的方向。

关键词：再生骨料附着水泥砂浆强化

TG−FTIR−MS和TG−GC/MS联用研究地沟油的热裂解特性

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中南大学学报（自然科学版） 2021年第4期52卷 1297-1306页

作者：张舒雯王亚思刘慧利丁宝平昆明理工大学冶金节能减排教育部工程研究中心云南昆明650093 昆明理工大学化学工程学院云南昆明650500

采用热重-红外-质谱联用技术(TG-FTIR-MS)和热重-气质联用技术(TG-GC/MS)分析地沟油热裂解过程中热重分析仪逸出气相产物的组成成分,探究地沟油的热裂解反应过程和热裂解特性。研究结果表明:地沟油热裂解释放气相产物的主要成分包括甘... 详细信息

采用热重-红外-质谱联用技术(TG-FTIR-MS)和热重-气质联用技术(TG-GC/MS)分析地沟油热裂解过程中热重分析仪逸出气相产物的组成成分,探究地沟油的热裂解反应过程和热裂解特性。研究结果表明:地沟油热裂解释放气相产物的主要成分包括甘油二酯、甘油一酯、脂肪酸、脂肪醛、脂肪酮、烷烃、烯烃、芳香烃和CO2等,气相产物的组成成分随温度升高发生显著变化。地沟油的热裂解过程分为3个阶段:第1阶段主要发生甘油三酯分子中C-O键的断裂生成甘油二酯、甘油一酯、脂肪酸和脂肪醛,第2阶段为热裂解第1阶段产生的酯类化合物及脂肪酸发生C-O键、C-C键的断裂和脱羧反应生成脂肪酸、脂肪醛、脂肪酮、烷烃、烯烃和CO2;第3阶段为脂肪酸的挥发和脱羧反应生成烷烃、烯烃和CO2以及共轭双烯与取代烯烃的Diels-Alder反应生成芳香烃。

关键词：地沟油热解气相产物热重−红外−质谱联用热重−气质联用

基于因果分析图法及层次分析法的空调工程施工质量控制

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上海理工大学学报 2013年第2期35卷 116-120页

作者：王瑾郭威刘金松王亚斯上海理工大学环境与建筑工程学院上海200093

将因果分析图法与层次分析法有机结合,联合应用于空调工程施工质量分析.首先用因果分析图法找出空调工程施工质量的影响因素,然后用层次分析法的判断矩阵对每层各影响因素的相对重要性给出判断.通过引入准确反映绝大多数人的分辨和判断... 详细信息

将因果分析图法与层次分析法有机结合,联合应用于空调工程施工质量分析.首先用因果分析图法找出空调工程施工质量的影响因素,然后用层次分析法的判断矩阵对每层各影响因素的相对重要性给出判断.通过引入准确反映绝大多数人的分辨和判断能力的标度,对判断矩阵采用近似计算的方法(方根法)计算判断矩阵的最大特征值λmax和相应因素排序的权值w,最终通过排序找出空调工程中质量控制的3个关键要素.

关键词：因果分析图法层次分析法空调工程质量控制

Kirigami-inspired multiscale patterning of metallic structures via predefined nanotrench templates

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Microsystems & Nanoengineering 2019年第1期5卷 59-69页

作者： Mengjie Zheng Yiqin Chen Zhi Liu Yuan Liu yasi wang Peng Liu Qing Liu Kaixi Bi Zhiwen Shu Yihui Zhang Huigao Duan School of Physics and Electronics State Key laboratory of Advanced Design and Manufacturing for Vehicle BodyHunan University410082 ChangshaPeople’s Republic of China College of Mechanical and Vehicle Engineering Hunan University410082 ChangshaPeople’s Republic of China AML Department of Engineering MechanicsAMLDepartment of Engineering Mechanics

Reliable fabrication of multiscale metallic patterns with precise geometry and size at both the nanoscale and macroscale is of importance for various applications in electronic and optical *** existing fabrication processes,which usually involve film deposition in combination with electron-beam patterning,are either timeconsuming or offer limited *** by the kirigami,an ancient handicraft art of paper cutting,this work demonstrates an electron-beam patterning process for multiscale metallic structures with significantly enhanced efficiency and *** to the kirigami,in which the final pattern is defined by cutting its contour in a paper and then removing the unwanted parts,we define the target multiscale structures by first creating nanotrench contours in a metallic film via an electron-beam-based process and then selectively peeling the separated film outside the *** with the conventional approach,which requires the exposure of the whole pattern,much less exposure area is needed for nanotrench contours,thus enabling reduced exposure time and enhanced geometric precision due to the mitigated proximity effect.A theoretical model based on interface mechanics allows a clear understanding of the nanotrench-assisted selective debonding behaviour in the peeling *** using this fabrication process,multiscale metallic structures with sub-10-nm up to submillimetre features can be reliably achieved,having potential applications for anti-counterfeiting and gap-plasmon-enhanced spectroscopy.

关键词： structures film template

钢结构被动式超低能耗住宅建筑气密性研究路径分析

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绿色建筑 2021年第4期13卷 75-76页

作者：王亚斯上海市建筑科学研究院有限公司上海201108

建筑气密性是决定建筑品质和性能的关键性指标之一。聚焦建筑气密性构造节点研究,重点阐述了钢结构被动式超低能耗住宅建筑气密性研究路径的思考。针对改善建筑气密、水密等问题,提出了研究路径,涵盖市场调研、设计优化、工艺研究、理... 详细信息

建筑气密性是决定建筑品质和性能的关键性指标之一。聚焦建筑气密性构造节点研究,重点阐述了钢结构被动式超低能耗住宅建筑气密性研究路径的思考。针对改善建筑气密、水密等问题,提出了研究路径,涵盖市场调研、设计优化、工艺研究、理论和试验论证、技术推广应用5个方面,可助力钢结构被动式超低能耗住宅建筑气密性技术研究和推广。

关键词：钢结构被动式超低能耗建筑气密性研究路径