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Exploration of the Mechanisms for the Low Sensitivity of Deposition Flux to Upstream Sediment Reduction in the North Passage, Yangtze Estuary

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China Ocean Engineering 2023年第4期37卷 533-546页

作者： WANG xiao-guang ZHANG Wei tong Chao-feng LEI Zhi-yi QIN Jie JI xiao-mei HUANG Rui The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

Deltas are densely populated industrialized regions,and home to important ports and navigation *** to human interferences,the Yangtze Estuary has experienced a significant reduction in sediment load caused by the Three Gorges Dam(TGD),as well as adjustment to local morphodynamics by the Deep-water Navigation Channel(DNC).While the dramatic reduction in sediment triggers the increased channel erosion,the deposition flux of the DNC located at the estuary mouth has little *** explore the physical mechanism of this phenomenon,a two-dimensional model is used to establish the relationship between sediment load and the sediment budget of channels based on the bathymetry in *** results show that the tidal reach and the inner estuary have a negative sediment *** the seasonal characteristics of water and sediment fluxes become less obvious *** analysis shows that the influence of upstream sediment load on deposition flux decreases along the channel,with a transition from deposition to erosion occurring in the tidal *** the last-level bifurcation,the annual siltation of sediment in the North Passage(NP)decreases by 4.5%with low *** is attributed to the reduction of sediment load partially mitigated by riverbed erosion and cascade *** addition,the lateral sediment supply,which accounts for 68%of the sediment input in the NP,is ***,this study strengthens the understanding of the relationship between sediment load and artificially deepened systems,thus allowing for better management of estuarine sediment and navigation channel.

关键词： delta navigation channel sediment load erosion and deposition sediment budget Yangtze Estuary

Synthesis,Characterization and DFT Calculation of a New Silver(I) Iodid Templated by Conjugated Cation:(ipq)_4Ag_4I_8

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Chinese Journal of Structural Chemistry 2006年第9期25卷 1148-1153页

作者： xiao guang-Can Center of Analysis and Measurement Fuzhou University Fuzhou Fujian 350002 China

A silver iodide, （ipq）4Ag418 1, has been synthesized in the presence of ipq （ipq = N-（isopentyl）-quinolinium） acting as a structure-directing reagent （SDA）. Compound 1 crystallizes in the triclinic system, space group PT, with a = 9.850（2）, b = 11.564（2）, c = 16.111（3） ,A ,α = 104.64（3）, β = 105.73（3）, γ = 94.37（3）o, V= 1688.3（7） A^3, Z = 2, D,= 2.205 g/cm^3, F（000） = 1042, C28H33Ag2l4N2, Mr= 1120.90, μ（MoKa） = 4.836 mm^-1, the final R = 0.0363 and wR = 0.0761 for 5465 observed reflections with 1 〉 2σ（I）. 1 consists of uncoordinated structure-directing molecule and inorganic moiety tuned by organic SDA. Tetrameric Ag4I8^4- anion in 1 is composed of edgesharing AgI4 tetrahedra and AgI3 planar triangles. Electrostatic interaction between organic counter cations and inorgan!c moieties is present and contributes to the crystal packing. 1 was further characterized with IR, UV-Vis, elemental analysis and cyclic voltammetry. Based on the crystal structure data, quantum chemical calculation with DFr method was used to reveal the electronic structure and optical property of 1.

关键词： coordination polymers template synthesis iodide quaternary ammonium

Blockage robust millimeter-wave networks

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Science China(Information Sciences) 2017年第8期60卷 77-79页

作者： guang YANG Ming xiao KTH Royal Institute of Technology

Millimeter-wave(mm Wave)technique(from around 24 GHz to 300 GHz)becomes a key enabler of high date rates for future mobile communications[1].In spite of many appealing benefits,mm Wave communications also encounter several critical challenges,i.e.,very weak capability in penetration,diffraction and high-order reflections,due to the short wavelength[2].That indicates,the transmission in mm Wave bands can be blocked easily if any obstacle,e.g.,human body or vehicle in motion,occurs on the propagation path.

关键词： Wave work in AP of as link TDMA Blockage robust millimeter-wave networks is or MBS MAC wave that

Circular Polarization of Fast Radio Bursts in the Curvature Radiation Scenario

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Research in Astronomy and Astrophysics 2022年第7期22卷 206-213页

作者： Hao tong Hong-guang Wang School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China

The curvature radiation is applied to the explanation of the circular polarization of fast radio bursts(FRBs).Significant circular polarization is reported in both apparently non-repeating and repeating *** radiation can produce significant circular polarization at the wing of the radiation *** the curvature radiation scenario,in order to see significant circular polarization in FRBs,(1) more energetic bursts,(2) bursts with electrons having higher Lorentz factor,and(3) a slowly rotating neutron star at the center are *** rotational period of the central neutron star may explain why some FRBs have high circular polarization,while others do *** possible difference in refractive index for the parallel and perpendicular components of electric field,the position angle may change rapidly over the narrow pulse window of the radiation *** position angle swing in FRBs may also be explained by this non-geometric origin,besides that of the rotating vector model.

关键词： stars:magnetars (stars:)pulsars:general polarization

Influence of severity and types of astigmatism on visual acuity in school-aged children in southern China

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International Journal of Ophthalmology(English edition) 2018年第8期11卷 1377-1383页

作者： Li-Li Wang Wei Wang xiao-tong Han Ming-guang He Zhongshan Ophthalmic Center State Key Laboratory of OphthalmologySun Yat-Sen University

AIM： To investigate the influence of astigmatism on visual acuity in school-aged children, and to define a cutoff for clinically significant astigmatism. METHODS： This is a population-based, cross-sectional study. Among 5053 enumerated children aged 5-15 y in guangzhou, 3729（73.8%） children aged 7-15 with successful cycloplegic auto-refraction（1% cyclopentolate） and a reliable visual acuity measurement were included. Ocular measurement included external eye, anterior segment, media and fundus and cycloplegic auto-refraction. Primary outcome measures included the relationship between severity and subtypes of astigmatism and the prevalence of visual impairment. Three criteria for visual impairment were adopted： best-corrected visual acuity（BCVA） ≤0.7, uncorrected visual acuity（UCVA） ≤0.5 or 〈0.7 in the right ***： Increases of cylinder power was significantly associated with worse visual acuity（UCVA： β=0.051, P〈0.01; BCVA： β=0.025, P〈0.001）. A substantial increase in UCVI and BCVI was seen with astigmatism of 1.00 diopter（D） or more. Astigmatism ≥1.00 D had a greater BCVI prevalence than cylinder power less than 1.00 D（OR=4.20, 95%CI： 3.08-5.74）, and this was also true for hyperopic, emmetropic and myopic refraction categories. Oblique astigmatism was associated with a higher risk of BCVI relative to with the rule astigmatism in myopic refractive category（OR=12.87, 95%CI： 2.20-75.38）.CONCLUSION： Both magnitude and subtypes of astigmatism influence the prevalence of visual impairment in school children. Cylinder ≥1.00 D may be useful as a cutoff for clinically significant astigmatism.

关键词： astigmatism visual acuity children population-based study

Fault-Tolerant Controlled Quantum Dialogue Using Logical Qubit

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Chinese Journal of Electronics 2018年第2期27卷 263-269页

作者： xiao Min LIU guang School of Cyber Security and Information Law Chongqing University of Posts and Telecommunications College of Computer Science and Technology Chongqing University of Posts and Telecommunications

The information leakage is a challenge in the design of Controlled quantum dialogue(CQD) protocols and the CQD protocol over noise channel has not been well researched. A CQD protocol without information leakage over an ideal channel is first proposed, where single photons are used to carrying secret information and pre-shared keys are used to authenticate identity and control information decoding for the prevention of information leakage, moreover, a novel kind of the unitary encoding operations with good property on the quantum operation discrimination are adopted to avoid active attacks from outside eavesdropper. By substituting logical qubits for single photons and constructing unitary encoding operations with the same property based on logical qubits,three fault-tolerant versions of the proposed CQD protocol are obtained, which can combat collective-dephasing,collective-rotation and all kinds of unitary collective noise,respectively. The security and efficiency analysis show the proposed protocols are appropriate for secure quantum dialogue in practice.

关键词： Controlled quantum dialogue(CQD) Single photon Logical qubit Noise channel

Hot deformation map and its application of GH4706 alloy

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International Journal of Minerals,Metallurgy and Materials 2014年第5期21卷 462-468页

作者： Shuo Huang Lei Wang Xin-tong Lian guang-pu Zhao Fang-fei Li xiao-min Zhang Key Lab for Anisotropy and Texture of Materials Northeastern University Department of High Temperature Materials Central Iron and Steel Research Institute

The hot deformation behaviors of GH4706 alloy were investigated using compression tests in a deformation temperature range from 900℃ to 1200℃ with a strain rate range of 0.001-1 s-1. Hot processing maps were developed on the basis of the dynamic material model and compression data. A three-dimensional distribution of power dissipation parameter （η） with strain rate and temperature reveals that η decreases in sensitivity with an increase in strain rate and a decrease in temperature. Microstructure studies show that the grain size of GH4706 alloy increases when η is larger than 0.32, and the microstructure exhibits local deformation when r/is smaller than 0.23. The hot processing map at the strain of 0.7 exposes a domain peak at 7=0.32 for the temperature between 940℃ and 970℃ with the strain rate from 0.015 s-1 to 0.003 s-1, and these are the optimum parameters for hot working.

关键词： superalloys nickel alloys deformation microstructure dynamic recrystallization

Dispersion modeling and health risk assessment of dioxin emissions from a municipal solid waste incinerator in Hangzhou,China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第1期13卷 69-78页

作者： xiao-jun MA Xu-guang JIANG Yu-qi JIN Hong-mei LIU xiao-dong LI tong CHEN Jian-hua YAN State Key Laboratory of Clean Energy Utilization Institute for Thermal Power E~Tgineering Zhejiang University Hangzhou 310027 China

The emission of dioxins from municipal solid waste incinerators(MSWIs) has become a widespread *** effect of meteorological parameters(wind speed,atmospheric stability and mixing height) on the hourly ground level concentration(GLC) of dioxins was estimated using air dispersion ***,the health risks of dioxin exposure were evaluated for children and adults using the Nouwen *** total environmental exposure via air inhalation and food ingestion was calculated,based on linear fit *** results indicate that potentially severe pollution from dioxins occurs at a wind speed of 1.5 m/s with atmospheric stability class *** addition,local residents in the study area are exposed to severe weather conditions most of the time,and the risk exposures for children are far higher than those for *** total exposure for children far exceeds the tolerable daily intake of dioxin recommended by the World Health Organization(WHO) of 1-4 pg TEQ/(kg·d) under severe weather *** from modeling calculations of health risk assessment were consistent with dioxin levels obtained during actual monitoring of emissions.

关键词： Dioxins Meteorology Air dispersion model Health risk assessment Dioxin exposure

Characteristics and efficiency of a new vibrating screen with a swing trace

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Particuology 2013年第5期11卷 601-606页

作者： Jianzhang xiao Xin tong School of Mechanical Engineering and Automation Huaqiao University

A new vibration type and motion characteristics were proposed according to the principle of manual sie- ving. A mechanical model of the new motion was established and the characteristics of the new vibrating screen were analyzed to establish its equation of motion by using the vibration theory, to include as tech- nological parameters, amplitude, movement velocity, and throwing index through theoretical calculation. The efficiency of particle screening was studied at different values of frequency and swing declination angle. The discrete element method （DEM） was used to simulate the screening with the swing trace. The functional relationship between screening efficiency and the parameters was fitted with the least square method. The results show that high frequency and large swing angle are suitable for small particles, while small values are suitable for particles close to the aperture size. Compared to the linear vibration trace, both screening efficiency and processing capacity were effectively improved.

关键词： Motion characteristicSwing traceScreening efficiencySimulation