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Experimental investigation on color variation mechanisms of structural light in Papilio maackii ménétriès butterfly wings

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Science China(Technological Sciences) 2007年第4期50卷 430-436页

作者： REN LuQuan QIU ZhaoMei HAN ZhiWu GUAN HuiYing WU LiYan Key Laboratory for Terrain-Machine Bionics Engineering Ministry of EducationCollege of Biological and Agricultural EngineeringJilin UniversityChangchun 130022China

The body color in animals results from billions of years of their natural evolution in order to evade natural enemies, catch quarries or display themselves beauty, in-vestigation on mechanisms of structural light is an important aspect of bionics. Based on the phenomenon of Papilio maackii ménétriès’ blue scales changing into green ones immediately after dropping some alcohol aqua on the underwing sur-face and soon returning back to the original color, the relationship between micro-structure, optics characteristic of scales and changing color effect were studied using the Olympus Stereomicroscope, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Ultraviolet (UV)-Visible Spectropho-tometer. The color variation mechanisms of blue scales of Papilio maackii mé-nétriès in Chinese Northeast were revealed in this paper. When visible lights trav-eled through the concaver structure with multilayer reflector and the filled medium with different refractive indices, the reflected lights in definite wavelengths pro-duced interference and color at that wavelength came into being. It has important academic reference value to biomimetics design of video stealth materials.

关键词： video stealth Papilio maackii ménétriès color variation of structural light

Assessing the influence of harvesting intensities on structural diversity of forests in south-west Germany

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Forest Ecosystems 2019年第3期6卷 249-260页

作者： Felix Storch Gerald Kadler Jürgen Bauhus Chair of Silviculture University of FreiburgD-79085 FreiburgGermany Department of Biometry Forest Research Institute of Baden-WürttembergD-79100 FreiburgGermany

Background: To increase ecosystem resilience and biodiversity, the maintenance and improvement of structural and compositional diversity of forests has become an important goal in forest management for many forest owners and jurisdictions. At the same time, future harvesting intensity (HI) may increase to meet the demand for woody biomass by an increasing bioeconomy sector. Yet, the influence of HI on forest structural diversity is largely unknown. Here, we address this issue by analyzing the relationship between HI and structural diversity based on large-scale national forest inventory (NFI) data, where the latter is quantified using a previously developed Forest Structure Index and HI is expressed as wood volume removal during the period 2002-2012 for the same inventory plots. Results: Our results show a surprisingly small impact of harvesting intensity on changes in structural diversity for most of the analysed types of forests. Only intense harvesting (> 80%-90% of initial growing stock) led to a significant reduction in structural diversity. At low to moderate HI most aspects of structural diversity were positively influenced. Only the quadratic mean DBH and the volume of large trees (≥ 40 cm DBH) were substantially negatively influenced at HI > 60% and 70% of initial growing stock, respectively. Conclusions: In several forest types, HI could be increased without a reduction in overall structural diversity. Hence, structural diversity in these selectively managed forests appears to be a very resistant forest property in relation to HI. Other indicators at stand and landscape scale may be needed to adjust levels of HI that are suited to maintain forest biodiversity.

关键词： Large-scale inventory structural diversity index Harvesting intensity Changes in structural diversity

EFFECT　OF　MILLING　INTENSITY　ON　structural　CHANGES　OF　MIXED　Al－Fe－Ni　POWDERS　IN　MECHANICAL　ALLOYING　PROCESS

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中国有色金属学会会刊：英文版 1996年第3期6卷 143-145,149页

作者： Liu Zuyan Liang Guoxian Wang Erde(School of Materials Science and Engineering,Harbin Institute of Technology, Harbin 150001) School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

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关键词： Al-Fe-Ni powder structural change milling intensity mechanical alloying

Comprehensive analysis of the influence of structural and dynamic parameters on the accuracy of nano-precision positioning stages

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Frontiers of Mechanical Engineering 2019年第3期14卷 255-272页

作者： Chengyuan LIANG Fang YUAN Xuedong CHEN Wei JIANG Lizhan ZENG Xin LUO State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074 China

Nano-precision positioning stages are characterized by rigid-flexible coupling systems. The complex dynamic characteristics of mechanical structure of a stage, which are determined by structural and dynamic parameters, exert a serious influence on the accuracy of its motion and measurement. Systematic evaluation of such influence is essential for the design and improvement of stages. A systematic approach to modeling the dynamic accuracy of a nano-precision positioning stage is developed in this work by integrating a multi-rigid-body dynamic model of the mechanical system and measurement system models. The influence of structural and dynamic parameters, including aerostatic bearing configurations, motion plane errors, foundation vibrations, and positions of the acting points of driving forces, on dynamic accuracy is investigated by adopting the H-type configured stage as an example. The approach is programmed and integrated into a software framework that supports the dynamic design of nano-precision positioning stages. The software framework is then applied to the design of a nano-precision positioning stage used in a packaging lithography machine.

关键词： nano-precision positioning stage analysis and design structural and dynamic parameters dynamic accuracy systematic modeling

Application of forecasting structural cracks technique of 3DMove in Chengdao buried hill

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Science China Earth Sciences 2005年第9期48卷 1403-1410页

作者： WU Shiguo1, 2, WANG Xiuling2, JI Yuxin2, LIU Yuzhen2 & HAN Wengong2 1. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China 2. Geophysical Research Institute, Shengli Oil Field, Dongying 257002, China Institute of Oceanology Chinese Academy of Sciences Qingdao China Geophysical Research Institute Shengli Oil Field Dongying Chin

3DMove software, based on the three-dimension structural model of geologic inter- pretation, can forecast reservoir cracks from the point of view of formation of the structural ge- ology, and analyze the characteristics of the cracks. 3DMove software dominates in forecasting cracks. We forecast the developments and directions of the cracks in Chengbei buried hill with the application of forecasting technique in 3DMove software, and obtain the chart about strain distributing on top in buried hill and the chart about relative density and orientation and the chart about the analysis of crack unsealing. In Chengbei 30 buried hill zone, north-west and north-east and approximately east-west cracks in Cenozoic are very rich and the main directions in every fault block are different. Forecasting results that are also verified by those of drilling approxi- mately accord with the data from well logging, the case of which shows that the technique has the better ability in forecasting cracks, and takes more effects on exploration and exploitation of crack reservoir beds in ancient buried hill reservoirs.

关键词： 3DMove, structural crack, buried hill, structural restoration.

Strong and Superhydrophobic Wood with Aligned Cellulose Nanofibers as a Waterproof structural Material

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Chinese Journal of Chemistry 2020年第8期38卷 823-829页

作者： Yongfeng Li Chaoji Chen Jianwei Song Chunpeng Yang Yudi Kuang Azhar Vellore Emily Hitz Mingwei Zhu Feng Jiang Yonggang Yao Amy Gong Ashlie Martini Liangbing Hu Department of Materials Science and Engineering University of MarylandCollege ParkMaryland20742USA Mechanical Engineering University of CaliforniaMercedCalifornia95343USA

Lightweight structural materials are important for the energy efficiency of applications,particularly those in the building ***,inspired by nature,we developed a strong,superhydrophobic,yet lightweight material by simple in situ growth of nano-SiO2 and subsequent densification of the wood *** situ generation of SiO2 nanoparticles both inside the wood channels and on the wood surfaces gives the material superhydrophobicity,with static and dynamic contact angles of 159.4°and 3°,*** of the wood to remove most of the spaces among the lumen and cell walls results in a laminated,dense structure,with aligned cellulose nanofibers,which in turn contributes to a high mechanical strength up to 384.2 MPa(7-times higher than natural wood).Such treatment enables the strong and superhydrophobic wood(SH-Wood)to be stable and have excellent water,acid,and alkaline *** high mechanical strength of SH-Wood combined with its excellent structural stability in harsh environments,as well its low density,positions the strong and superhydrophobic wood as a promising candidate for strong,lightweight,and durable structural materials that could potentially replace steel.

关键词： fibers proof structural

New few parameters differential evolution algorithm with application to structural identification

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第1期6卷 1-14页

作者： Rita Greco Ivo Vanzi Department of Civil Engineering Environmental Territory Building and Chemical Polytechnic University of Bari Department of Engineering and Geology University of Chieti-Pescara "G.d'Annunzio"

Differential evolution algorithm(DEA) is a stochastic, population-based global optimization method. In this paper, we propose new schemes for both mutation and crossover operators in order to enhance the performances of the standard DEA. The advantage of these proposed operators is that they are "parameters-less", without a tuning phase of algorithm parameters that is often a disadvantage of DEA. Once the modified differential evolutions are presented, a large comparative analysis is performed with the aim to assess both correctness and efficiency of the proposed operators. Advantages of proposed DEA are used in an important task of modern structural engineering that is mechanical identification under external dynamic loads. This is because of the importance of using a "parametersless" algorithm in identification problems whose characteristics typically vary strongly case by case, needing of a continuous set up of the algorithm proposed. This important advantage of proposed optimizers, in front of other identification algorithms, is used to develop a computer code suitable for the automatic identification of a simple supported beam subject to an impact load, that has been tested both using numerical simulations and real standard tests dynamic. The results point out that this algorithm is an interesting candidate for standard applications in structural identification problems.

关键词： Differential evolution Parametric identification structural identification Optimization

Tunable structural coloration of ultrathin zirconia nanotubes film

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Rare Metals 2023年第10期42卷 3304-3310页

作者： Xi-Di Sun Hui-Wen Yu Cheng-Yan Zhao Jing Zhang Yi Shi Li-Jia Pan Collaborative Innovation Center of Advanced Microstructures School of Electronic Science and EngineeringNanjing UniversityNanjing210093China CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing100083China

Zirconium(Zr) is a rare metal widely used in aero space and military ***,its single color does not meet the requirements of camouflage and ***,a series of ultrathin structural colorations of Zr by coating it with a on... 详细信息

关键词： structural film coating

Geological analysis and physical modeling of structural pumping in high effective formation of Kela 2 gas field

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Science China Earth Sciences 2006年第10期49卷 1070-1078页

作者： ZHAO Wenzhi1, WANG Hongjun1, SHAN Jiazeng2, WANG Zecheng1 & XU Dafeng1 1. Research Institute of Petroleum Exploration and Development, Petrochina, Beijing 100083, China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China Research Institute of Petroleum Exploration and Development Petrochina Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

In a 3-D closed geological body, in case “structural expanding” inside is induced by stress, it can produce the pressure difference between the expanding cell and surrounding rock, then generate a pumping force directed toward the cell and accelerate the directional flow of fluid in the strata. The structural style and conditions of gas reservoir-formation in the Kuqa depression are favorable to the structural pumping. According to similarity principle, a physical modeling of structure formation and gas filling process of the Kela 2 gas field has justified the occurrence of structural pumping and its important role in gas-reservoir formation with high efficiency under the compressive and well-sealed circumstance. Therefore, authors propose that structural pumping is an important mechanism of gas reservoir-formation with high efficiency in the Kuqa depression.

关键词： Kela 2 gas field, structural pumping, gas-reservoir formation mechanism, high efficiency,physical modeling.