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From Self-assembled Monolayers to Chemically Patterned Brushes:Controlling the Orientation of Block Copolymer Domains in Films by Substrate Modification

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Chinese Journal of Polymer Science 2016年第6期34卷 659-659,660-678页

作者： xiao-sa Jin Yuan-yuan Pang 季生象 Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Block copolymer lithography is emerging as one of the leading technologies for patteming nanoscale dense features. In almost all potential applications of this technology, control over the orientation of cylindrical and lamellar domains is required for pattern transfer from the block copolymer film. This review highlights the state-of-art development of brushes to modify the substrates to control the assembly behaviors of block copolymers in films. Selected important contributions to the development of self-assembled monolayers, polymer brushes and mats, and chemically patterned brushes are discussed.

关键词： Self-assembly Block copolymer Neutral brush Chemical pattern Wetting behavior.

Crustal deformation and tectonic levels of Nujiang Gorge since the Miocene

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Science China Earth Sciences 2018年第1期61卷 93-108页

作者： LIU ZhiCheng JI JianQing sa xiao CHEN YaPeng ZHONG DaLai China Earthquake Disaster Prevention Center Beijing 100029 China School of Earth and Space Sciences Peking University Beijing 100871 China Power China beijing Engineering Corporation Limited Beijing 100024 China Institution of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Crustal deformation shows different patterns at different depths due to changes in the physical properties of *** levels can be defined based on the geometry and deformation mechanisms of crustal deformation patterns. Nujiang Gorge, with a high riverbed drop, great erosion depth, and strong deformation, has rock exposures at different tectonic levels and thus provides an ideal lab for deformation study. This paper takes the Nujiang Gorge from Chawalong to Fugong as the object to identify structural deformation patterns at different depths through field study and deformation analysis. At depth, the primary form of deformation is flow deformation, as shown on the outcrops at Maji. Ductile shear deformation can be found in many outcrops within the study region, e.g., the Gaoligong dextral shear zone and Puladi-Songta sinistral shear zone that lie to the south and north of Maji, respectively. Further to the north of Puladi, the dominated deformation pattern is similar fold and dense sub-vertical foliation. In addition, brittle faults, as evidence of shallow deformation, can be seen overprinting on the deeper deformation features all over the region. Based on those observations, this paper identifies four tectonic levels from depth to the surface: flow deformation, ductile shear deformation, similar fold, and brittle fault deformation, all of which result from the NEE-SWW compressive stress field. Further evidence from studies on the region′s thermal evolution and regional tectonics suggests that the development of different tectonic levels is closely linked to the discrepant uplift or denudation since the Miocene(~21 Ma).

关键词： Tectonic level Nujiang Gorge Flow deformation Ductile shear deformation Thermal evolution

Density Effects on Plant Height Growth and Inequality in Sunflower Populations

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Journal of Integrative Plant Biology 2006年第5期48卷 513-519页

作者： sa xiao Shu-Yan Chen Lu-Qiang Zhao Gang Wang Laboratory of Arid Agroecology School of Life Sciences Lanzhou University Lanzhou 73000 China

Comparisons between competing and non-competing sunflower （Helianthus annuus L.） populations demonstrate pronounced effects of density on plant height growth, height-to-crown width ratio, and s popuiaUon＇s height inequality. In the present study, non-destructive measurements of height and the prolected crown area of sunflower plants were taken at seven times from emergence to fruit maturation in even-aged monospeclflc stands with initial densities of 1, 4, 16, and 64 plants/m^2. The mean height of populations Increased and then decreased with increasing population density; the height Inequalities of uncrowded populations decreased during stand growth, whereas the height inequaiiUes of crowded popuisUons decreased first and then increased during stand development. The interindlvidual relationships between the relative height growth rate and height within uncrowded populations became significantly negative during population growth, whereas these relationships were negative first and then became positive during the development of crowded populations. In the uncrowded populations, the static Interindlvldual relationship between height-to-crown width ratio and volume was positive, whereas for the crowded population these relationships became negative with increasing competition for light. The data suggest that the plastic responses of plant height and height-to-crown width ratio to light competition will become more Intense with increasing competition Intensity. The results of the present study argue strongly for the Importance of size-dependent Individual-level plastic responses due to size-asymmetric light competition In generating the variations in population height inequality.

关键词： height inequality light competition plasticity size dependent.

A Throughput-Aware Joint Vehicle Route and Access Network Selection Approach Based on SMDP

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China Communications 2020年第5期17卷 243-265页

作者： Jiandong Xie sa xiao Ying-Chang Liang Li Wang Jun Fang National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 116024China Center for Intelligent Networking and Communications(CINC) University of Electronic Science and Technology of China(UESTC)Chengdu 611731China Research and Development Center Huawei TechnologiesStockholm 16494Sweden

In intelligent transportation system(ITS), the interworking of vehicular networks(VN) and cellular networks(CN) is proposed to provide high-data-rate services to vehicles. As the network access quality for CN and VN is location related, mobile data offloading(MDO), which dynamically selects access networks for vehicles, should be considered with vehicle route planning to further improve the wireless data throughput of individual vehicles and to enhance the performance of the entire ITS. In this paper, we investigate joint MDO and route selection for an individual vehicle in a metropolitan scenario. We aim to improve the throughput of the target vehicle while guaranteeing its transportation efficiency requirements in terms of traveling time and distance. To achieve this objective, we first formulate the joint route and access network selection problem as a semi-Markov decision process(SMDP). Then we propose an optimal algorithm to calculate its optimal policy. To further reduce the computation complexity, we derive a suboptimal algorithm which reduces the action space. Simulation results demonstrate that the proposed optimal algorithm significantly outperforms the existing work in total throughput and the late arrival ***, the heuristic algorithm is able to substantially reduce the computation time with only slight performance degradation.

关键词： mobile data offloading network selection route selection semi-Markov decision process vehicular network

Tailoring the separation performance of a carbon nanotube-based mixed matrix membrane decorated with metal–organic framework

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Chinese Journal of Chemical Engineering 2023年第12期64卷 87-95页

作者： Hui-Yong Wu Hong-Xin Fu Yu Liu xiao-sa Zhang Wen-Ze Li Jian Luan College of Science Shenyang University of Chemical TechnologyShenyang 110142China College of Sciences Northeastern UniversityShenyang 110819China

Synthesis of mixed matrix membranes(MMM)using carbon nanotubes(CNTs)has shown great prospects for achieving excellent selective separation because of its special ***,the preparation of highly selective MMM faces challenges,which is attributed to the obstacles encountered by CNTs dispersion in polymer matrix and elimination of interface defects.A novel CNT-based composite decorated with metal–organic framework(MOF)was synthesized and applied to the preparation of *** was post modified,and then carboxyl groups were inserted on the outer surface of *** synthetic MMM(Cu-MOF-en@MWCNT)not only has selective adsorption on dyes,but also has selective photodegradation on *** method of using CNTs to wrap the outside of MOF has great potential in dye *** performance of MMM was further improved by decorating MOF on the filler to improve the selectivity to the designated dye.

关键词： Composites Carbon nanotube Metal-organic framework Organic crosslinking Selectivity Adsorbents

A modified multi-group model of angular and momentum distribution of cosmic ray muons for thickness measurement and material discrimination of slabs

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Nuclear Science and Techniques 2018年第2期29卷 111-117页

作者： sa xiao Wei-Bo He Ming-Cong Lan Ying Chen Mao-Bing Shuai Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China Science and Technology on Surface Physics and Chemistry Laboratory Mianyang 621900China

Muon tomography is a capable imaging technique to measure the geometry of high-Z objects. However,most existed algorithms used in muon tomography have obscured the effects of angular distribution and momentum spectra of cosmic ray muons and reduced the spatial resolution. We present a modified multi-group model that takes into account these effects and calibrates the model by the material of lead. Performance tests establish that the model is capable of measuring the thickness of a Pb slab and identifying the material of an unknown slab on a reasonable exposure timescale, in both cases of complete and incomplete angular data. Results show that the modified multi-group model is helpful for improvements in image resolution in real applications.

关键词： Muon tomography Modified multi-group model Angular distribution Momentum spectra

Effects of size variation and spatial structure on plastic response of plant height to light competition

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Chinese Science Bulletin 2010年第12期55卷 1135-1141页

作者： CHEN ShuYan ZHANG JiaLin JIA Peng XU Jin WANG Gang xiao sa Key Laboratory of Arid and Grassland Ecology of Ministry of Education School of Life Science Lanzhou University Lanzhou 730000 China

Plants only interact with neighbors over restricted distances,so local conditions are of great significance for *** this study,a spatially-explicit,individual-based model was constructed to explore the effects of size variation and spatial structure on adaptive plasticity of plant height in response to light *** the model a plant maintains its height at an optimal value in order to maximize its growth rate,and this optimal height increases with the increase of the intensity of light competition experienced by the individual *** the spatial pattern of the population is non-uniform or there is size variation among individual plants,the height growth curves of individuals different from each other vary due to the differences in the local light environment,and there is also variation in the allocation of photosynthate to height growth among the individual *** is no ESS height or height growth strategy on which all plants will *** results indicate that the plasticity of plants' height growth reactions to the light competition should be considered at the individual level and they argue strongly for the importance of the spatial pattern and neighborhood effects in generating the diversity of heights and height growth strategies in plant population.

关键词：空间结构光响应竞争塑料株高空间分布格局变异单株生长曲线

Material discrimination using cosmic ray muon scattering tomography with an artificial neural network

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Radiation Detection Technology and Methods 2022年第2期6卷 254-261页

作者： Weibo He Dingyue Chang Rengang Shi Maobing Shuai Yingru Li sa xiao Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China Key Laboratory of Green Manufacturing of Superlight Elastomer Materials of State Ethnic Affairs Commission Hubei Minzu UniversityEnshi 445000China

Introduction Muon scattering tomography(MST)can be employed to scan cargo containers and vehicles for special nuclear materials by using cosmic ***,the flux of cosmic ray muons is relatively low for direct ***,the detection has to be done in a short timescale with small numbers of muons to satisfy the demands of practical *** In this paper,we propose an artificial neural network(ANN)algorithm for material discrimination using *** muon scattering angles were simulated using Geant4 to formulate the training set,and the muon scatter angles were measured by Micromegas detection system to create the test *** The ANN-based algorithm presented here ensures a discrimination accuracy of 98.0%between aluminum,copper and tungsten in a 5 min measurement of 4×4×4 cm^(3)blocks.

关键词： Muon scattering tomography Cargo container inspection Material discrimination Artificial neural network classifier

Recent Advances in Passive Digital Image Security Forensics： A Brief Review

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Engineering 2018年第1期4卷 29-39页

作者： Xiang Lin Jian-Hua Li Shi-Lin Wang Alan-Wee-Chung Liew Feng Cheng xiao-sa Huang School of Cyber Security Shanghai Jiao Tong University Shanghai 200240 China School of Information and Communication Technology Gold Coast Campus Griffith University Southport OLD 4222 Australia

With the development of sophisticated image editing and manipulation tools, the originality and authen- ticity of a digital image is usually hard to determine visually, In order to detect digital image forgeries, various kinds of digital image forensics techniques have been proposed in the last decade, Compared with active forensics approaches that require embedding additional information, passive forensics approaches are more popular due to their wider application scenario, and have attracted increasing academic and industrial research interests, Generally speaking, passive digital image forensics detects image forgeries based on the fact that there are certain intrinsic patterns in the original image left during image acqui- sition or storage, or specific patterns in image forgeries left during the image storage or editing, By ana- lyzing the above patterns, the originality of an image can he authenticated, In this paper, a brief review on passive digital image forensic methods is presented in order to provide a comprehensive introduction on recent advances in this rapidly developing research area, These forensics approaches are divided into three categories based on the various kinds of traces they can he used to track-that is, traces left in image acquisition, traces left in image storage, and traces left in image editing, For each category, the forensics scenario, the underlying rationale, and state-of-the-art methodologies are elaborated, Moreover, the major limitations of the current image forensics approaches are discussed in order to point out some possible research directions or focuses in these areas,

关键词： Digital image forensicsImage-tampering detectionMultimedia security