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Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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science China Earth sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2, WANG Qingfei1,2 , huang Dinghua3., WAN Li4. yang Liqiang1,2 & GAO Bangfei1,2 1. State Key Laboratory of Geological Processes and Mineral Resources, China {3. of Geo{4.s, Beijing 100083. China 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing {4. of Ministry of Education, China {3. of Geo- {4.s, Beijing 100083. China 3. Faculty of Earth {4.s, China {3. of Geo{4.s, Wuhan 4.0074. China 4. {14. of Mathematics and information {4., Guangzhou {3., Guangzhou 5104.5, China 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing technology of Ministry of Education China University of Geosciences Beijing 100083 China 3. Faculty of Earth sciences China University of Geosciences Wuhan 430074 China 4. school of Mathematics and information {3. Guangzhou University Guangzhou 510405 China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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science China Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2, CUI Yuezhi3. huang Zhenli4. XUE Gang1 & YU Wentao1 1. State Key Laboratory of Crystal Materials, Shandong university, Jinan 250100, China 2. {3. of {4. {4. and Engineering, Shandong university, Jinan 250100, China 3. Department of Chemical Engineering, Light Industry College of Shandong, Jinan 250100, China 4. Key Laboratory of Biomedical Photonics, Ministry of Education, Huazhong university of {4. and technology, Wuhan 4.0074. China 1. State Key Laboratory of Crystal Materials Shandong University 250100 Jinan China 2. school of information science and Engineering Shandong University 250100 Jinan China 3. Department of Chemical Engineering Light Industry College of Shandong 250100 Jinan China 4. Key Laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2,4.dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2,4.dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2-methyl-4.6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2). NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064.nm fundamental laser, NEt-1 powder crystals radiate a 2-order harmonic light with an intensity 4..8 times that of urea. The Λ typed NMe-2 molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P21 space group. Its powder crystals exhibit a 2-order harmonic intensity 4..2 times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2-order nonlinear optical (NLO) efficiency on the micro 2-order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

Wideband chaos generation using a VCSEL with intensity modulation optical injection for random number generation

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science China(information sciences) 2024年第6期67卷 457-458页

作者： Yu huang Shuangquan GU Yuhang FENG Yigong yang Shuiying {3. Pei ZHOU Nianqiang LI school of Optoelectronic science and Engineering & Collaborative Innovation Center of Suzhou Nano science and {3. Soochow University State Key Laboratory of Integrated Service Networks Xidian University Key Lab of Advanced Optical Manufacturing Technologies of Jiangsu Province & Key Lab of Modern Optical Technologies of Education Ministry of China Soochow University

Physical random numbers have been widely used in modern network society,such as the generation of cryptographic keys for classical and quantum cryptography systems[1].Among the many sources of physical entropy,chaotic semiconductor lasers have attracted wide attention due to their desired characteristics including larger bandwidth,low cost,and monolithic integration[2].

关键词： Optical signal processing

Molten metal-organic complex to synthesize versatile ultrathin nonlayered oxides

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Nano Research 2024年第4期17卷 3147-3155页

作者： Kaisi Liu Jiabin Wu Qun Li Hongrun Jin Yongxin Luo Bei Qi Simin Dai jianquan Zhao Liang huang Jun Zhou Hubei Key Laboratory of Biomass Fibers and Eco-Dyeing&Finishing Wuhan Textile UniversityWuhan 430200China Wuhan National Laboratory for Optoelectronics School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhan 430074China Analytical and Testing Center Huazhong University of Science and TechnologyWuhan 430074China

Two-dimensional(2D)materials have attracted a great deal of research interest because of their unique electrical,magnetic,optical,mechanical,and catalytic properties for various *** date,however,it is still difficult to fabricate most functional oxides as 2D materials unless they have a layered ***,we report a one-step universal strategy for preparing versatile non-layered oxide nanosheets by directly annealing the mixture of metal nitrate and dimethyl imidazole(2-MI).The 2-MI plays the key role for 2D oxides since 2-MI owns a very low molten point and sublimation temperature,in which its molten liquid can coordinate with metal ions,forming a metal-organic framework,and easily puffing by its gas molecules.A total of 17 materials were prepared by this strategy,including non-layered metal oxide nanosheets as well as metal/metal oxide loaded nitrogen-doped carbon *** as-prepared cobalt particle-loaded nitrogen-doped carbon nanosheets(Co@N/C)exhibit remarkable bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalytic activity and ***,the Zn-air battery utilizing a Co@N/C catalyst exhibits high power density of 174.3.mW·cm^(-2).This facile strategy opens up a new way for large-scale synthesis of 2D oxides that holds great potential to push 2D oxides for practical applications.

关键词： non-layered oxide nanosheet metal/metal oxide@N/C oxygen evolution reaction(OER) oxygen reduction reaction(ORR) Zn-air battery

Brillouin Klein space and half-turn space in three-dimensional acoustic crystals

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science Bulletin 2024年第13期69卷 2050-2058页

作者： Zhenxiao Zhu Linyun yang Jien Wu Yan Meng xiang Xi Bei Yan Jingming Chen Jiuyang Lu Xueqin {3. Weiyin Deng Ce Shang Perry Ping Shum Yihao yang Hongsheng Chen Kexin xiang Gui-Geng Liu Zhengyou Liu Zhen Gao State Key Laboratory of Optical Fiber and Cable Manufacture technology Department of Electronic and Electrical EngineeringSouthern University of Science and TechnologyShenzhen 518055China school of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China Key Laboratory of Artificial Micro-and Nanostructures of Ministry of Education and school of Physics and technology Wuhan UniversityWuhan 430072China King Abdullah university of science and technology(KAUST) Physical Science and Engineering Division(PSE)Thuwal 23955-6900Saudi Arabia Interdisciplinary Center for Quantum information State Key Laboratory of Modern Optical InstrumentationZJU-Hangzhou Global Science and Technology Innovation CenterCollege of Information Science and Electronic EngineeringZJU-UIUC InstituteZhejiang UniversityHangzhou 310027China Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore Institute for Advanced Studies Wuhan UniversityWuhan 430072China

The Bloch band theory and Brillouin zone(BZ)that characterize wave-like behaviors in periodic mediums are two cornerstones of contemporary physics,ranging from condensed matter to topological *** theoretical breakthrough revealed that,under the projective symmetry algebra enforced by artificial gauge fields,the usual two-dimensional(2D)BZ(orientable Brillouin two-torus)can be fundamentally modified to a non-orientable Brillouin Klein bottle with radically distinct manifold ***,the physical consequence of artificial gauge fields on the more general three-dimensional(3.)BZ(orientable Brillouin three-torus)was so far ***,we theoretically discovered and experimentally observed that the fundamental domain and topology of the usual 3. BZ can be reduced to a non-orientable Brillouin Klein space or an orientable Brillouin half-turn space in a 3. acoustic crystal with artificial gauge *** experimentally identify peculiar 3. momentum-space non-symmorphic screw rotation and glide reflection symmetries in the measured band ***,we experimentally demonstrate a novel stacked weak Klein bottle insulator featuring a nonzero Z2 topological invariant and self-collimated topological surface states at two opposite surfaces related by a nonlocal twist,radically distinct from all previous 3. topological *** discovery not only fundamentally modifies the fundamental domain and topology of 3. BZ,but also opens the door towards a wealth of previously overlooked momentum-space multidimensional manifold topologies and novel gaugesymmetry-enriched topological physics and robust acoustic wave manipulations beyond the existing paradigms.

关键词： Momentum-space non-symmorphic symmetry Brillouin Klein space and half-turn space Acoustic Klein bottle insulator Self-collimated topological surface states

Calibration based universal JPEG steganalysis

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science in China(Series F) 2009年第2期52卷 260-268页

作者： huang FangJun1,2 & huang jiwu1,2 1 {3. of {{4. science and technology,Sun Yat-Sen university,Guangzhou 510275,China 2 Guangdong Key Lab. of {{4. Security technology,Sun Yat-Sen university,Guangzhou 510275,China school of information science and {3. Sun Yat-Sen University Guangzhou 510275 China Guangdong Key Lab. of information Security technology Sun Yat-Sen University Guangzhou 510275 China

For steganalysis of JPEG images, features derived in the embedding domain appear to achieve a preferable performance. However, with the existing JPEG steganography, the minor changes due to the hidden secret data are not easy to be explored directly from the quantized block DCT （BDCT） coefficients in that the energy of the carrier image is much larger than that of the hidden signal. In this paper, we present an improved calibration-based universal JPEG steganalysis, where the microscopic and macroscopic calibrations are combined to calibrate the local and global distribution of the quantized BDCT coefficients of the test image. All features in our method are generated from the difference signal be- tween the quantized BDCT coefficients of the test image and its corresponding microscopic calibrated image, or calculated as the difference between the signal extracted from test image and its corresponding macroscopic calibrated image. The extracted features will be more effective for our classification. Moreover, through using the Markov empirical transition matrices, both magnitude and sign dependencies along row scanning and column scanning patterns existed in intra-block and inter-block quantized BDCT coefficients are employed in our method. Experimental results demonstrate that our proposed scheme outperforms the best effective JPEG steganalyzers having been presented.

关键词： JPEG steganography steganalysis microscopic calibration macroscopic calibration

Performance analysis of network coding for multicast relay system over Nakagami-m fading channels

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science China(information sciences) 2011年第11期54卷 2338-2348页

作者： ZHAO Rui 1,yang LvXi 2 & huang YongMing 2 1 school of {3. {{4. and Engineering,Huaqiao university,Xiamen 3.1021,China 2 school of {3. {{4. and Engineering,Southeast university,Nanjing 210096,China 1. school of information science and Engineering Huaqiao University Xiamen 361021 China2. School of Information Science and Engineering Southeast University Nanjing 210096 China

The outage probability performance of network coding for multicast relay system is analyzed in Nakagami-m fading *** transmission strategies,i.e.,complex field network coding (CFNC) and amplify-and-forward network coding (AFNC),are applied in the system,and the approximate expressions of outage probability are derived at high SNR and the conclusion is reached that the system diversity gains of two transmission strategies are both 2m,as is verified by numerical *** results also show that CFNC can outperform both AFNC and direct transmission without relay in the performances of system outage probability,sum rate and symbol error ratio.

关键词： multicast relay system network coding outage probability diversity gain

Modelling and simulation study on dynamic pollution accumulation process of composite insulator

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High Voltage 2024年第3期9卷 601-613页

作者： Zhongyi yang Dongxiong Liu xiangjun Zeng Caijin Fan Xin yang Yafei {3. school of Electrical and information Engineering Changsha University of Science and TechnologyChangshaChina State Key Laboratory of HVDC Electric Power Research InstituteCSGGuangzhouChina

With the widespread application of composite insulators in transmission lines,exploring the accumulation mechanism of pollution particles on composite insulator surfaces is of importance to ensure the safe and steady operation of the power *** the current theoretical shortcomings,this study categorises the accumulation process of particles on the insulator surface into three stages,namely‘spatial motion’,‘surface collision’,and‘surface motion’.The motion and rotation velocities in a multi-physics field are calculated in the spatial motion *** the surface collision stage,a parameter called‘neck height’is introduced to determine the optimum mechanics theory,and the normal deposition criterion is *** the surface motion stage,the sliding displacement and rolling displacement on the surface are calculated based on the rotation speed of the particles.A dynamic pollution accumulation model of the composite insulator is estab-lished based on the normal deposition criterion and tangential ***,numerical simulations are performed by using the finite element *** results show that the proposed model agrees with the actual insulator pollution accu-mulation,and the deposition model is still applicable for various types of composite insulators operating in different applied *** deposition probability of particles increases with the increasing particle *** the surface motion stage,particle displacement increases with particle size and wind velocity.

关键词： composite displacement dynamic

Hyperspectral remote sensing identification of marine oil emulsions based on the fusion of spatial and spectral features

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Acta Oceanologica Sinica 2024年第3期43卷 139-154页

作者： Xinyue huang Yi Ma Zongchen Jiang Junfang yang school of Geography and Marine science Nanjing UniversityNanjing 210023China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Marine Telemetry technology Innovation Center Ministry of Natural ResourcesQingdao 266061China Harbin Institute of technology Harbin 150001China China university of Petroleum(East China) Qingdao 266061China

Marine oil spill emulsions are difficult to recover,and the damage to the environment is not easy to *** use of remote sensing to accurately identify oil spill emulsions is highly important for the protection of marine ***,the spectrum of oil emulsions changes due to different water *** remote sensing and deep learning can use spectral and spatial information to identify different types of oil ***,hyperspectral data can also cause information redundancy,reducing classification accuracy and efficiency,and even overfitting in machine learning *** address these problems,an oil emulsion deep-learning identification model with spatial-spectral feature fusion is established,and feature bands that can distinguish between crude oil,seawater,water-in-oil emulsion(WO),and oil-in-water emulsion(OW)are filtered based on a standard deviation threshold–mutual information *** oil spill airborne hyperspectral data,we conducted identification experiments on oil emulsions in different background waters and under different spatial and temporal conditions,analyzed the transferability of the model,and explored the effects of feature band selection and spectral resolution on the identification of oil *** results show the following.(1)The standard deviation–mutual information feature selection method is able to effectively extract feature bands that can distinguish between WO,OW,oil slick,and *** number of bands was reduced from 22{4.to 13.4.after feature selection on the Airborne Visible Infrared Imaging Spectrometer(AVIRIS)data and from 126 to 100 on the S185 data.(2)With feature selection,the overall accuracy and Kappa of the identification results for the training area are 91.80%and 0.86,respectively,improved by 2.62%and 0.0{4.and the overall accuracy and Kappa of the identification results for the migration area are 86.53.and 0.80,respectively,improved by 3.{4.%and 0.05.(3.The oil emulsion id

关键词： oil emulsions identification hyperspectral remote sensing feature selection convolutional neural network(CNN) spatial-temporal transferability