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A new look at roles of the cryosphere in sustainable development

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Advances in Climate Change Research 2019年第2期10卷 124-131页

作者： WANG Xiaoming LIU shi-wei ZHANG Jing-Lin State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100190 China

While the cryosphere may bring in adverse impacts on natural and built environment, it may also provide benefits resulting from cryosphere services. By looking into the effect of the cryosphere on human-being, the study develops a unified approach in the analysis of cryospheric risks and services, with one focusing on the adverse impacts by cryospheric hazards and another emphasizing on the benefits that people can obtain from the natural capitals in the cryosphere. Meanwhile, climate change could further alter and complicate the roles of the cryosphere, not only by the changes in risks to cryospheric hazards, but also the changes in services that could potentially add more risks. The study further proposed a risk-based approach for the development of climate adaptation in the cryosphere. The approach essentially takes options to reduce exposure and vulnerability of societies to cryospheric hazards, and to better manage natural capitals and demands together with enhancing utility of the cryosphere, so as to maintain the benefit of cryosphere services in a sustainable way. The study further addresses the role of cryosphere services in strengthening sustainable development in terms of its relation with the sustainable development goals (SDGs), and provides a preliminary results on how the services contributes to SDGs. Overall, the approach developed in this study creates a new way to comprehensively assess the effect of cryosphere changes on our society and identify measures to maximize the benefit while minimizing the risk in relation to the cryosphere.

关键词： Cryosphere Cryospheric science Cryosphere service Cryosphere change Climate change impact Climate change adaptation Risk management

Atlas Compatibility Transformation:A Normal Manifold Learning Algorithm

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International Journal of Automation and computing 2015年第4期12卷 382-392页

作者： Zhong-Hua Hao shi-wei Ma Fan Zhao School of Mechatronic Engineering and Automation Shanghai Key Laboratory of Power Station Automation TechnologyShanghai University

Over the past few years,nonlinear manifold learning has been widely exploited in data analysis and machine *** paper presents a novel manifold learning algorithm,named atlas compatibility transformation(ACT),It solves two problems which correspond to two key points in the manifold definition:how to chart a given manifold and how to align the patches to a global coordinate space based on *** the first problem,we divide the manifold into maximal linear patch(MLP) based on normal vector field of the *** the second problem,we align patches into an optimal global system by solving a generalized eigenvalue *** with the traditional method,the ACT could deal with noise datasets and fragment ***,the mappings between high dimensional space and low dimensional space are *** on both synthetic data and real-world data indicate the effection of the proposed algorithm.

关键词： Nonlinear dimensionality reduction manifold learning normal vector field maximal linear patch ambient space.

Tectonic evolution of the Dabashan orocline, central China: Insights from the superposed folds in the eastern Dabashan foreland

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Geoscience Frontiers 2013年第6期4卷 729-741页

作者： wei shi Jianhua Li Mi Tian Guoli Wu Key Laboratory of Neotectonic Movement and Geohazard Ministry of Land and Resources Institute of Geomechanics Chinese Academy of Geological Sciences Wuxi Research Institute of Petroleum Geology Institute of Geology and Geophysics Chinese Academy of Sciences

The Dabashan orocline is situated in the northwestern margin of the central Yangtze block,central *** studies have defined the orthogonal superposed folds growing in its central-western segment thereby confirming its two-stage tectonic evolution *** mapping has revealed that more types of superposed folds have developed in the eastern segment of the orocline,which probably provides more clues for probing the structure and tectonic history of the Dabashan *** this paper,based on geological mapping,structural measurements and analyses of deformation,we have identified three groups of folds with different trends （***-,NE-and nearly E-trending folds） and three types of structural patterns of superposed folds in the eastern Dabashan foreland （***-axial,oblique,and conjunctional superposed folds）.In combination with geochronological data,we propose that the synaxial superposed folds are due to two stages of ～N-S shortening in the west and north of the Shennongjia massif,and that oblique superposed folds have been resulted from the superposition of the NW-and NE-trending folds onto the early ～ E-W folds in the east of the Shennongjia massif in the late Jurassic to early *** conjunctional folds are composed of the NW-and NE-trending folds,corresponding to the regional-scale dual-orocline in the eastern Sichuan as a result of the southwestward expansion of the Dabashan foreland during late Jurassic to early Cretaceous,coeval with the northwestward propagation of the Xuefengshan *** of the structure and geochronology of the belt shows that the Dabashan orocline is a combined deformation belt primarily experiencing a twostage tectonic evolution history in Mesozoic,initiation of the Dabashan orocline as a foreland basin along the front of the Qinling orogen in late Triassic to early Jurassic due to collisional orogeny,and the final formation of the Dabashan orocline owing to the southwestward propagation of th

关键词： Dabashan foreland belt Superposed folds Orocline Paleo-stress field Intra-continental orogeny Late Jurassic

Optical and SAR image registration based on improved nonsubsampled wavelet transform for sea islands

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Acta Oceanologica Sinica 2014年第5期33卷 86-95页

作者： shi wei SU Fenzhen WANG Ruirui LU Yongduo Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Collaborative Innovation Center of South China Sea Studies Nanjing University Beijing Forestry University National Marine Environmental Forecasting Center State Oceanic Administration

Homologous feature point extraction is a key problem in the optical and synthetic aperture radar （SAR） image registration for islands. A new feature point extraction method using a threshold shrink operator and non-subsampled wavelet transform （TSO-NSWT） for optical and SAR image registration was proposed. Moreover, the matching for this proposed feature was different from the traditional feature matching strategies and was performed using a similarity measure computed from neighborhood circles in low-frequency bands. Then, a number of reliably matched couples with even distributions were obtained, which assured the accuracy of the registration. Application of the proposed algorithm to SPOT-5 （multi-spectral） and YG-1 （SAR） images showed that a large number of accurately matched couples could be identified. Additionally, both of the root mean square error （RMSE） patterns of the registration parameters computed based on the TSO-NSWT algorithm and traditional NSWT algorithm were analyzed and compared, which further demonstrated the effectiveness of the proposed algorithm. The algorithm can supply the crucial step for island image registration and island recognition.

关键词： image registration islands South China Sea wavelet transform threshold shrink operator

Kolmogorov's ε-Entropy of Bounded Sets in Discrete Spaces and Attractors of Dissipative Lattice Systems

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Acta Mathematica Sinica,English Series 2007年第2期23卷 313-320页

作者： Sheng Fan ZHOU Qiu Li JIA wei shi Department of Applied Mathematics Shanghai Normal University Department of Mathematics and Physics He'nan University of Science and Technology Department of Mathematics Shanghai University

We obtain an estimate of the upper bound for Kolmogorov＇s ε-entropy for the bounded sets with small ＂tail＂ in discrete spaces, then we present a sufficient condition for the existence of a global attractor for dissipative lattice systems in a reflexive Banach discrete space and establish an upper bound of Kolmogorov＇s ε-entropy of the global attractor for lattice systems.

关键词： Kolmogorov's ε-entropy discrete space dissipative lattice system global attractor

The application of metal-organic frameworks in electrocatalytic nitrogen reduction

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Chinese Chemical Letters 2020年第7期31卷 1768-1772页

作者： Yihang Wang Qiang Li wei shi Peng Cheng Key Laboratory of Advanced Energy Materials Chemistry(MOE)and Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) College of ChemistryNankai UniversityTianjin 300071China

In recent years,the research of nitrogen reduction reaction(NRR)under ambient conditions has attracted wide attention for their relatively low energy consumption,in which rational design of electrocatalysts is the key to achieve high-performance ***-organic frameworks(MOFs),as a new kind of porous material,have been intensively studied in the past few decades owing to not only their structural versatility and tunability but also intrinsic *** to their structural features,MOFs also have potential applications in mild condition electrocatalysis of *** this review,the recently experimental and theoretical studies of MOFs in NRR electrocatalysts are briefly summarized.

关键词： Nitrogen reduction reaction Metal-organic frameworks Electrocatalysis Nanomaterials

Uniform to Accelerated Crystal Twisting Transition in Deuterate Polyethylene/Poly(ethylene-alt-propylene) Blend Films

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Chinese Journal of Polymer Science 2014年第9期32卷 1260-1270页

作者： Li-na Zhang wei-chao shi 韩志超程贺 State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences China Spallation Neutron Source Institute of High Energy Physics Chinese Academy of Sciences

A uniform to accelerated crystal twisting transition is observed in deuterate polyethylene/poly（ethylene-alt- propylene）（d-PE/PEP） blend films. And the band period is a function of initial d-PE concentration, quench depth and annealing time of phase separation. As Keith and Padden suggested, twisting of lamella is due to the unbalanced stress on its both sides, which can supply a satisfying explanation to banded spherulites formed in homogeneous systems. When it comes to d-PE/PEP blend system, in homogeneous 99% d-PE/PEP （weight fraction of d-PE） blend film, the formation of banded spherulite is observed as a result of uniform twisting of ribbon like d-PE lamellae along the radial direction. With the amorphous PEP piling up, it transfers into accelerated edge-on to fiat-on twisting due to crystallization assisted phase separation. The mechanism can be interpreted as following： d-PE molecules must inter-diffuse to the twisting growth front to continue the secondary nucleation and growth process. Meanwhile, the amorphous PEP molecules are rejected and accumulated at the twisting growth front. Once the d-PE lamella begins to twist because of unbalanced stress on both sides, the accumulated rubber phase at the growth front strengthens the unbalance and accelerates the edge-on to flat-on twisting. The concentration wave propagates further away with constant speed, and leads to concentric ring pattern with periodic nonuniform twisting along the radial direction. Since this is a kinetic effect, the band period can be controlled through initial d-PE concentration, quench depth and annealing time of phase separation. Our result shows that crystallization assisted phase separation can modify lamella growth kinetic pathway, thereby assisting concentric ring pattern formation.

关键词： Polyethylene/poly(ethylene-alt-propylene) (d-PE/PEP) blend Phase separation Crystallization.

Scattering of S0 Lamb Mode from a Blind Hole in a Plate Using Mindlin/Mindlin Plate Theory

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Chinese Physics Letters 2014年第3期31卷 86-90页

作者： ZHANG Hai-Yan YAO Jie-Cong MA shi-wei School of Communication and Information Engineering Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University Shanghai 200072 Shanghai Key Laboratory of Power Station Automation Technology School of Mechatronic Engineering and Automation Shanghai University Shanghai 200072

An analytical model of Lamb wave scattering from a circular blind hole in isotropic plates is presented using the Mindlin plate theory for describing in-plane and flexural wave modes simultaneously. The model makes use of the wave function expansion technique and the boundary conditions at the hole edge to evaluate the scattered far fields of three fundamental guided wave modes. Comparisons are made to existing approximate models using Poisson/Kirchhoff theory and Poisson/Mindlin theory and a 3D model using the exact 3D equations. The results reveal that the present model is more consistent with the exact 3D model at higher frequencies than existing approximate models.

关键词： LAMB waves RESEARCH SCATTERING (Physics) MINDLIN theory EQUATIONS PHYSICS research

A Mechanism Study of a Novel Acid-Activatable Michael-Type Fluorescent Probe for Thiols

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Chinese Journal of Chemical Physics 2015年第3期28卷 277-287,I0001页

作者： Yao Tong Chun-guang Dai Yi Ren shi-wei Luo Department of Chemistry University of Science and Technology of China Hefei 230026 China College of Chemistry and State Key Laboratory of Biotherapy Sichuan University Chengdu 610064 China

A Michael addition is usually taken as a base-catalysed reaction. However, our synthesized 2-（quinolin-2-ylmethylene） malonic acid （QMA） as a Michael-type thiol fluorescent probe is acid-active in its sensing reaction. In this work, based on theoretic calculation and experimental study on 7-hydroxy-2-（quinolin-2-ylmethylene） malonic acid, we demonstrated that QMA as a Michael acceptor is acid-activatable, i.e., it works only in solutions at pH〈7, and the lower the pH of solutions is, the higher reactivity QMA has. In alkaline solution, the malonate QMA[-2H＋]2- cannot react with both RSand RSH. In contrast, 2-（quinolin-2- ylmethylene） malonic ester （QME）, the ester of QMA, reveal a contrary pH effect on its sensing reaction, that is, it can sense thiols in alkaline solutions but not in acidic solutions, like a normal base-catalysed Michael addition. The values of activation enthalpies from theoretic calculation support the above sensing behavior of two probes under different pH conditions. In acidic solutions, the protonated QMA is more highly reactive towards electrophilic attack over its other ionized states in neutral and alkaline solutions, and so can react with lowly reactive RSH. In contrast, there is a big energy barrier in the interaction of QME with RSH （acidic solutions）, and the reaction of QME with the highly reactive nucleophile RS- is a low activation energy process （in alkaline solutions）. Theoretic calculation reveals that the sensing reaction of QMA undergoes a 1,4-addition process with neutral thiols （RSH）, and a 1,2-addition pathway for the sensing reaction of QME with RS-. Therefore, the sensing reaction of QMA is an acid-catalysed Michael addition via a 1,4-addition, and a normal base-catalysed Michael addition via a 1,2-addition.

关键词： Fluorescent probe Thiols Michael addition DFT calculation Transitionstate Activation enthalpy