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Journal of Ocean University of China 2020年第2期19卷 361-368页

作者： ZAI Xuerong liu Ang tian Yuhua CHAI Fanggang fu Yubin College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China

A novel sensor for ocean electric field testing has been fabricated by polyacrylonitrile-based on carbon fibers with electro-chemical *** surface profile characteristics of the carbon fibers were characterized by scanning electron microscope,Fourier transform infrared spectra and contact *** voltammetry and Tafel curves have been used to study its electro-chemical *** identical electrodes in sea water as the electric field sensor will swiftly respond to applied electric field which causes positive and negative ions to move in opposite direction,resulting in a electric potential difference(ΔE).Test result indicates that the offset potential is typically below 1 m V with a drift of 60-170μVd^-*** self noise level is 1.07 nV√Hz^(1/2)@1 *** electric field response indicates that the modified electrode pair shows better response to AC sine signal of amplitude and frequency(5 mV and 1 mHz)respectively than its *** electric field response model of the modified electrodes is creatively presented according to its electric double layer capacitance and Faraday *** advantages of the carbon fiber electric field electrode will make it have potential application prospect.

关键词： carbon fiber electrode electro-chemical oxidation modification electro-chemical performance electric field response electric field test

Ultracompact meta-imagers for arbitrary all-optical convolution

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Light(Science & Applications) 2022年第4期11卷 595-607页

作者： Weiwei fu Dong Zhao Ziqin Li Songde liu Chao tian Kun Huang Department of Optics and Optical Engineering University of Science and Technology of ChinaHefeiAnhui 230026China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefeiAnhui 230088China. Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefeiAnhui 230026China

Electronic digital convolutions could extract key features of objects for data processing and information identification in artificial intelligence,but they are time-cost and energy consumption due to the low response of *** massless photons enable high-speed and low-loss analog convolutions,two existing all-optical approaches including Fourier fItering and Green's function have either limited functionality or bulky volume,thus restricting their applications in smart ***,we report aloptical convolutional computing with a metasurface-singlet or-doublet imager,considered as the third approach,where its point spread function is modified arbitrarily via a complex-amplitude meta-modulator that enables functionality-unlimited *** one-and two-dimensional spatial differentiation,we demonstrate real-time,parallel,and analog convolutional processing of optical and biological specimens with challenging pepper-salt denoising and edge enhancement,which significantly enrich the toolkit of all-optical *** meta-imager approach bridges multi-functionality and high-integration in all-optical convolutions,meanwhile possessing good architecture compatibility with digital convolutional neural networks.

关键词： convolution enable arbitrary

Synthesis, Crystal Structure and Characterization of a New Hydrogen-bonded Organic Framework

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Chinese Journal of Structural Chemistry 2021年第8期40卷 1082-1087,971页

作者： SUN Jing liu Hai-Xiong liu tian-fu Jinshan College Fujian Agriculture and Forestry UniversityFuzhou 350002China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

The hydrogen-bonded organic framework(PFC-32),constructed by tetrahydroxyquinone(THQN)and diethylamine(DEA),was readily prepared via hydrothermal synthesis in DEF(N,N-diethylformamide).PFC-32 was characterized by PXRD,IR,UV-Vis,TGA and photoluminescence(PL).Single crystal analysis reveals that PFC-32 shows a three-dimensional(3 D)framework,where the THQN anions are coplanar and separated by DEA ***-32 displays intrinsic photoluminescence property owing to the alleviation of the aggregation-caused quenching(ACQ)effect caused byπ-πstacking.

关键词： tetrahydroyquinone diethylamine hydrogen-bonded organic framework

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联体婴儿分离手术家属主观幸福感变化及手术伦理学评估

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四川医学 2011年第10期32卷 1529-1531页

作者：吴天福刘铭谭毅何延政廖斌泸州医学院附属医院儿外科血管外科胸外科四川泸州646000

目的探讨联体婴儿分离手术家属主观幸福感变化及与分离手术伦理学实践的关系。方法纳入我科经治3例连体婴儿,均为足月产对称胸腹联体双胎,于我院行联体婴儿分离术,伦理学评价由我院伦理委员会进行。记录患儿直系亲属手术前后及随访期间M... 详细信息

目的探讨联体婴儿分离手术家属主观幸福感变化及与分离手术伦理学实践的关系。方法纳入我科经治3例连体婴儿,均为足月产对称胸腹联体双胎,于我院行联体婴儿分离术,伦理学评价由我院伦理委员会进行。记录患儿直系亲属手术前后及随访期间MUNSH评分变化。结果①3例联体婴儿均顺利接受联体婴儿分离术,其中例2中小双因严重心脏畸形术后48h因心衰、呼衰死亡;②3例联体婴儿分离术后发育正常,未见手术并发症;③术后患儿直系亲属MUNSH评分评分显著高于术前(P<0.05)。结论联体婴儿分离术是涉及生命权和健康权的社会伦理问题,因重视分离术术前伦理学评价。连体婴儿分离术的进行应尊重家属意见、社会背景、文化差异及手术风险等多因素进行评价。

关键词：联体婴儿伦理学评估主观幸福感

A force transfer mechanism for triggering landslides during rainfall infiltration

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Journal of Mountain Science 2018年第11期15卷 2480-2491页

作者： liu Gang TONG fu-guo ZHAO Yi-tong tian Bin College of Hydraulic & Environment Engineering China Three Gorges University

Shallow slope failures induced by rainfall infiltration occur frequently, and the relevant triggering mechanisms have been widely ***-induced landslides are widely recognized to be caused by increases in soil weight, seepage force and pore water pressure or decreases in soil mechanical properties. However, even when all these factors are considered, some landslides still cannot be explained well. The increased pore water pressure in a slope reduces the effective stress of the soil and may trigger slope failure. Similarly, the pore gas pressure in a slope also reduces the effective stress of the soil but has been neglected in previous studies. As the viscosity of air is nearly negligible when compared with that of water, the pore gas pressure spreads faster, and its influence is wider, which is harmful for the stability of the slope. In this paper, the effects of pore gas pressure are considered in a shallow slope stability analysis, and a self-designed experiment is conducted to validate the force transfer *** simulation results show that the pore gas pressure in the slope increases sharply at different locations under heavy rainfall conditions and that the pore gas pressure causes a rapid decrease in the slope safety factor. Laboratory experimental results show that the pore gas pressure throughout the whole unsaturated zone has the same value, which indicates that the gas pressure could spread quickly to the whole sample.

关键词： Landslide Force transfer mechanism Rainfall infiltration Water-air two-phase flow

A Review of Research on Warm-Sector Heavy Rainfall in China

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Advances in Atmospheric Sciences 2019年第12期36卷 1299-1307页

作者： Jianhua SUN Yuanchun ZHANG Ruixin liu Shenming fu fuyou tian Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Beijing Municipal Weather Forecast Center Beijing 100089China National Meteorological Center China Meteorological AdministrationBeijing 100081China

Warm-sector heavy rainfall (WSHR) events in China have been investigated for many years. Studies have investigated the synoptic weather conditions during WSHR formation, the categories and general features, the triggering mechanism, and structural features of mesoscale convective systems during these rainfall events. The main results of WSHR studies in recent years are summarized in this paper. However, WSHR caused by micro- to mesoscale systems often occurs abruptly and locally, making both numerical model predictions and objective forecasts difficult. further research is needed in three areas:(1) The mechanisms controlling WSHR events need to be understood to clarify the specific effects of various factors and indicate the influences of these factors under different synoptic background circulations. This would enable an understanding of the mechanisms of formation, maintenance, and organization of the convections in WSHR events.(2) In addition to South China, WSHR events also occur during the concentrated summer precipitation in the Yangtze River-Huaihe River Valley and North China. A high spatial and temporal resolution dataset should be used to analyze the distribution and environmental conditions, and to further compare the differences and similarities of the triggering and maintenance mechanisms of WSHR events in different regions.(3) More studies of the mechanisms are required, as well as improvements to the model initial conditions and physical processes based on multi-source observations, especially the description of the triggering process and the microphysical parameterization. This will improve the numerical prediction of WSHR events.

关键词： warm-sector heavy rainfall synoptic weather conditions triggering mechanism South China

An effective poly（p-phenylenevinylene） polymer adhesion route toward three-dimensional nitrogen-doped carbon nanotube/reduced graphene oxide composite for direct electrocatalytic oxygen reduction

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Nano Research 2016年第11期9卷 3364-3376页

作者： Yu fu Chungui tian Fangyuan liu Lei Wang Haijing Yan Bai Yang State Key Laboratory of Supramolecular Structure and Materials College of Chemistry Jifin University Changchun 130012 China Key Laboratory of functional Inorganic Material Chemistry Ministry of Education of the People's Republic of China Heilongjiang University Harbin 150080 China

Heteroatom-doped nanocarbons have excellent potential for use in the oxygen reduction reaction （ORR）. However, construction of three-dimensional （3D） N-doped carbon materials with good electrocatalytic performance remains a challenge. Herein, a poly（p-phenylenevinylene）（PPV）-precursor adhesion route was developed for construction of 3D N-doped reduced graphene oxide-PPV calcined-carbon nanotubes （N-RGO-PPV（c）-CNTs）. In the synthesis, the PPV- precursor plays the role of a ＂glue＂ for strong adhesion of the RGO and CNTs. At high temperature, PPV can undergo transformation from the glassy state to a viscous state. Thus, the N-RGO-PPV（c）-CNT composite with multi-porous structure and ridge-like folded graphene flakes could be formed during nitridation at high temperature, which was favorable for production of more active sites for the ORR. As an ORR catalyst, the N-RGO-PPV（c）-CNT composites exhibited superior catalytic activity in alkaline electrolyte. The obtained onset potential （Eonset） of 0.92 V and catalytic current density of 5.7 mA·cm^-2 at 0.6 V （vs. RHE） are comparable to those of the 20% Pt/C composite （0.98 V and 5.2 mA·cm^-2）. The electron transfer number for the N-RGO-PPV（c）-CNT catalyst was about 3.99, which is close to that of the 20% Pt/C （4.01） catalyst. Notably, the optimal N-RGO-PPV（c）-CNT catalyst shows better durability and methanol tolerance than commercial 20% Pt/C. The good performance of the N-RGO-PPV（c）-CNT catalyst for the ORR may be attributed to the synergistic effects of the unique 3D structure for effective mass-transfer, the effective N-doping for production of more active sites, and the good contact between the RGO and CNTs for easy charge-transfer.

关键词： three dimensionalgraphene/carbonnanotube nitrogen-doped electrocatalysis oxygen reduction

A Sulfonate-based Metal-organic Framework for the Transformation of CO and Epoxides into Cyclic Carbonates

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Chinese Journal of Structural Chemistry 2020年第11期39卷 2027-2032页

作者： XUE Huan LI Tao YIN Qi HUANG Ge liu tian-fu College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

An interesting metal-organic framework(MOF) PFC-31 was synthesized by a simple solvothermal reaction. X-ray crystallography reveals that PFC-31 crystallizes in monoclinic system, space group P21/c with a = 6.8410(17), b = 20.123(5), c = 7.689(2) ?, β = 104.239(7)°, V = 1026.0(5) ?3, Z = 2, C16 H22 CuN4 O8 S2, Mr = 526.03, μ = 1.322 mm-1, Dc = 1.703 g/cm3, F(000) = 542, GOOF = 1.214, R = 0.0975 and w R = 0.2324. According to X-ray analysis, PFC-31 shows one-dimensional chain constructed by Cu(Ⅱ) centers coordinating with two pyridine groups, two sulfonate groups and two DMF molecules. Owing to the orderly functionalized sulfonate group and Lewis metal sites, PFC-31 exhibits good catalytic capability for CO2 cycloaddition of epoxide under normal pressure and temperature.

关键词： metal-organic frameworks sulfonate group Lewis metal sites cycloaddition

Preparation and Properties of Ultrathin Flexible Expanded Graphite Film via Adding Natural Rubber

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Chinese Journal of Polymer Science 2019年第8期37卷 806-814页

作者： Yan-Ling Mo Yu-Xin tian Yu-Hang liu Feng Chen Qiang fu College of Polymer Science and Engineering Sichuan University State Key Laboratory of Polymer Materials Engineering

Expanded graphite(EG) films exhibit potential use in a wide field including thermal management, conductive applications,and electromagnetic interference(EMI) shielding. However, their poor tensile strength and brittleness are crucial deficiencies for commercial applications. To address these defects, in our work, natural rubber(NR) is employed to improve EG films for better mechanical strength and flexibility. The origin of the strengthening effect of EG films by the addition of natural rubber mainly arises from the formation of a simulate shell structure. Compared to the neat EG films, the addition of merely 2 wt% NR can give rise to superior ductility. further, the loading of 10 wt% NR realizes a significant mechanical enhancement of the EG/NR films, i.e., 2.4 and 11.4 times increase in tensile strength and elongation at break, respectively. Besides, EG/NR films containing 10 wt% NR can still sustain excellent thermal and electric conductivities of 173 W·m^-1·K^-1 and 75 S·cm^-1, respectively. furthermore, a very high EMI of 41.4 dB is achieved as the film thickness reaches 50 μm. Thus, the lightweight EG/NR films with comprehensive performance as well as their virtue of green and simple large-scale preparation endow them with the possibility of designing next-generation flexible electronics.

关键词： Expanded graphite Natural rubber Composite films Thermal and electric properties

Hot Deformation Behavior and Microstructural Characteristics of Ti–46Al–8Nb Alloy

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Acta Metallurgica Sinica(English Letters) 2018年第9期31卷 933-944页

作者： tian-Rui Li Guo-Huai liu Mang Xu tian-Liang fu Yong tian Ra-Ja Devesh Kumar Misra Zhao-DongWang State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Laboratory for Excellence in Advanced Steel Research Department of MetallurgicalMaterials and BiomedicalEngineeringUniversity of Texas at E1 PasoE1 PasoTX 79968-0521USA

Hot deformation behavior, microstructural evolution and flow softening mechanism were investigated in Ti-46A1-8Nb alloy via isothermal compression approach. The true stress-strain curves exhibited typical work hardening and flow softening, in which the dependence of the peak stress on temperature and strain rate was obtained by hyperbolic sine equation with Zener-Hollomon （Z） parameter, and the activation energy was calculated to be 446.9 kJ/mol. The microstructural analysis shows that the alternate dark and light deformed ribbons of Al-rich and Nb-rich regions appeared and were associated with local flow involving solute segregation. The Al segregation promoted flow softening mainly arising from the recrystaUization of V phase with low stacking fault energy. The coarse recrystallized 7 and several massive phase were observed at grain boundaries. While in the case of Nb segregation, t/B2 phase harmonized bending of lamellae, combined with the growth of recrystallized γ grains and α ＋ β ＋ γ→α＋ γ transition under conditions of temperature and stress, leading to the breakdown of α2/γ lamellar colony. During the hot compression process, gliding and dissociation of dislocations occurred in γ phase that acted as the main softening mechanism, leading to extensive γ twins and cross twins in α/γ lamellae and at grain boundaries. In general, homogeneous microstructure during the hot defor- mation process can be obtained in TiAl alloy with high Nb addition and low Al segregation. The deformation substructures intrinsically promote the formability of Ti--46Al-8Nb alloy.

关键词： Titanium aluminides Deformation behavior Activation energy Dynamic recrystallization Local flow softening