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Corrosion Resistance of Graphene-Reinforced Waterborne Epoxy Coatings

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Journal of Materials Science & Technology 2016年第5期32卷 425-431页

作者： Shuan Liu lin gu Haichao Zhao Jianmin Chen Haibin Yu Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective Technologies Ningbo Institute of Materials Technologies and Engineering Chinese Academy of Sciences

Graphene （G） was dispersed uniformly in water and used as an inhibitor in waterborne epoxy coatings. The effect of dispersed G on anticorrosion performance of epoxy coatings was evaluated. The composite coatings displayed outstanding barrier properties against H20 molecule compared to the neat epoxy coating. Open circuit potential （OCP）, Tafel and electrochemical impedance spectroscopy （EIS） analysis confirmed that the corrosion rate exhibited by composite coatings with 0.5 wt% G was an order of magnitude lower than that of neat epoxy coating. Salt spray test results revealed superior corrosion resistance offered by the composite coating.

关键词： Waterborne epoxy coating Graphene Corrosion resistance Electrochemical impedance spectroscopy(EIS)

Efficient detection methods for amplify-and-forward relay-aided device-to-device systems with full-rate space-time block code

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Frontiers of Information Technology & Electronic Engineering 2017年第6期18卷 788-795页

作者： Kang-li ZHANG Cong ZHANG Fang-lin gu Jian WANG College of Electronic Science and Engineering National University of Defence Technology School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University

Relay-aided device-to-device (D2D) communication is a promising technology for the next-generation cellular network. We study the transmission schemes for an amplify-and-forward relay-aided D2D system which has multiple antennas. To circumvent the prohibitive complexity problem of traditional maximum likelihood (ML) detection for full-rate space-time block code (FSTBC) transmission, two low-complexity detection methods are proposed, i.e., the detection methods with the ML-combining (MLC) algorithm and the joint conditional ML (JCML)detector. Particularly, the method with the JCML detector reduces detection delay at the cost of more storage and performs well with parallel implementation. Simulation results indicate that the proposed detection methods achieve a symbol error probability similar to that of the traditional ML detector for FSTBC transmission but with less complexity, and the performance of FSTBC transmission is significantly better than that of spatial multiplexing transmission. Diversity analysis for the proposed detection methods is also demonstrated by simulations.

关键词： Device-to-device Relay Detection Full-rate space-time block code

Fine-grained Mg−1Mn−0.5Al−0.5Ca−0.5Zn alloy with high strength and good ductility fabricated by conventional extrusion

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Transactions of Nonferrous Metals Society of China 2022年第2期32卷 483-492页

作者： guang-lin gu Xiang-nan KE Fa-ping HU Shu-jie ZHAO guo-bin WEI Yan YANG Xiao-dong PENG Wei-dong XIE Joint International Laboratory for Light Alloys College of Materials Science and EngineeringChongqing UniversityChongqing 400044China guizhou Anda Aviation Forging Co. Ltd.Anshun 561005China

Mg−1Mn−0.5Al−0.5Ca−0.5Zn(wt.%)alloy was fabricated by conventional extrusion at 673 K with an extrusion ratio of 25:1,followed by aging at 473 *** microstructure was characterized by scanning electron microscopy,electron back-scattered diffraction,and transmission electron *** mechanical properties were determined by the tensile *** peak-aged sample shows fine recrystallized grains with an average grain size of 1.7μ*** fraction of Al−Ca particles in the alloy increases significantly after peak ***,botháañandác+añdislocations were observed to remain in the alloy after hot ***,the peak-aged sample exhibits simultaneously high strength and good ductility with the ultimate tensile stress,tensile yield stress,and tension fracture elongation of 320 MPa,314 MPa,and 19.0%,respectively.

关键词： Mg−Mn−Al−Ca−Zn alloy fine grain precipitate strength ductility

Dynamic evolution of shear rate-dependent behavior of rock discontinuity under shearing condition

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Journal of Central South University 2021年第6期28卷 1875-1887页

作者： gu lin-lin WANG Zhen ZHANG Feng GAO Fei WANG Xiao Department of Civil Engineering Nanjing University of Science and TechnologyNanjing 210094China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact The Army Engineering University of PLANanjing 210014China Department of Civil Engineering Nagoya Institute of TechnologyNagoya 4668555Japan School of Civil Engineering Southeast UniversityNanjing 210096China

Rock blocks sliding along discontinuities can cause serious disasters,such as landslides,earthquakes,or rock *** shear rate-dependent behavior is a typical time-dependent behavior of a rock discontinuity,and it is closely related to the stability of a rock *** further study the shear rate-dependent behavior of rock discontinuities,shear tests with alternating shear rates(SASRs)were conducted on rock discontinuities with various surface *** dynamic evolution of the shear rate dependency was studied in detail based on the shear test results,and three stages were identified with respect to the shear stress and shear deformation *** test results revealed that dynamic changes in shear stiffness and the energy storage abilities of the rock discontinuities occurred in relation to the shear rate-dependent behavior of crack growth,which increased with an increase in normal stress and/or the joint roughness *** stage of decreasing shear stiffness corresponded to a stage of noticeable shear rate-dependency,and the shear rate was found to have no influence on the initial crack stress.

关键词： shear rate-dependent behavior rock discontinuity dynamic evolution initial crack stress

Two-Dimensional Electron Gas with High Mobility Forming at BaO/SrTiO_(3) Interface

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Chinese Physics Letters 2022年第4期39卷 41-46页

作者： Cheng Cao Shengru Chen Jun Deng Gang Li Qinghua Zhang lin gu Tian-Ping Ying Er-Jia guo Jian-Gang guo Xiaolong Chen Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 101408China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

Two-dimensional electron gas(2DEG)with high electron mobility is highly desired to study the emergent properties and to enhance future device *** we report the formation of 2DEG with high mobility at the interface between rock-salt Ba O and perovskite Sr Ti O_(3).The interface consists of the ionically compensated Ba O_(1-δ) layer and the electronically compensated Ti O_(2) layer,which is demonstrated as a perfect interface without lattice *** so-formed interface features metallic conductivity with ultralow square resistance of7.3×10^(-4)Ω/□at 2 K and high residual resistance ratios R_(300 K)/R_(2 K) up to *** electron mobility reaches69000 cm^(2)·V^(-1)·s^(-1)at 2 K,leading to Shubnikov–de Haas oscillations of *** functional theory calculations reveal that the effective charge transfers from Ba O to the Ti 3d_(xy) orbital occur at the interface,leading to the conducting Ti O_(2) *** work unravels that Ba O can adapt itself by removing oxygen to minimize the lattice mismatch and to provide substantial carriers to Sr Ti O_(3),which is the key to forming 2DEGs with high mobility at the interfaces.

关键词： interface Electron resistance

Origin of the low formation energy of oxygen vacancies in CeO_(2)

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Chinese Physics B 2022年第10期31卷 488-492页

作者： Han Xu Tongtong Shang Xuefeng Wang Ang Gao lin gu Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

Oxygen vacancies play a crucial role in determining the catalytic properties of Ce-based catalysts,especially in oxidation *** design of catalytic activity requires keen insight into oxygen vacancy formation *** this work,we investigate the origin of oxygen vacancies in CeO_(2)from the perspective of electron density via high-energy synchrotron powder x-ray *** refinement results indicate that there is no obvious hybridization between bonded Ce and O atoms in CeO_(2).Subsequent quantitative topological analysis of the experimental total electron density reveals the closed-shell interaction behavior of the Ce-O *** results of first-principles calculation indicate that the oxygen vacancy formation energy of CeO_(2)is the lowest among three commonly used redox *** findings indicate the relatively weak bond strength of the Ce-O bond,which induces a low oxygen vacancy formation energy for CeO_(2)and thus promotes CeO_(2)as a superior catalyst for oxidation *** work provides a new direction for design of functional metal oxides with high oxygen vacancy concentrations.

关键词： CeO_(2) oxygen vacancy synchrotron x-ray diffraction electron-density distribution

Method for rapid warning and activity concentration estimates in online waterγ-spectrometry systems

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Nuclear Science and Techniques 2024年第3期35卷 1-12页

作者： Meng Wang Yi gu Mao-lin Xiong Liang-Quan Ge Qing-Xian Zhang guo-Qiang Zeng Heng Lu Sheng-Liang guo College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province (Chengdu University of Technology)Chengdu 610059China Chengdu New Ray Technology Co.Ltd Chengdu 610052China

Onlineγ-spectrometry systems for inland waters,most of which extract samples in situ and in real time,are able to produce reliable activity concentration measurements for waterborne radionuclides only when they are distributed relatively uniformly and enter into a steady-state diffusion regime in the measurement *** protect residents’health and ensure the safety of the living environment,better timeliness is required for this measurement *** address this issue,this study established a mathematical model of the online waterγ-spectrometry system so that rapid warning and activity estimates can be obtained for water under non-steady-state(NSS)*** addition,the detection efficiency of the detector for radionuclides during the NSS diffusion process was determined by applying the computational fluid dynamics technique in conjunction with Monte Carlo *** this basis,a method was developed that allowed the online waterγ-spectrometry system to provide rapid warning and activity concentration estimates for radionuclides in *** analysis of the NSS-mode measurements of^(40)K radioactive solutions with different activity concentrations determined the optimum warning threshold and measurement time for producing accurate activity concentration estimates for *** experimental results show that the proposed NSS measurement method is able to give warning and yield accurate activity concentration estimates for radionuclides 55.42 and 69.42 min after the entry of a 10 Bq/L^(40)K radioactive solution into the measurement chamber,*** times are much shorter than the 90 min required by the conventional measurement ***,the NSS measurement method allows the measurement system to give rapid(within approximately 15 min)warning when the activity concentrations of some radionuclides reach their respective limits stipulated in the guidelines for Drinking-water Quality of the WHO,suggesting that this method con

关键词： Water radioactivity monitoring Dynamic detection efficiency Rapid warning Activity estimation

Individualized Traditional Chinese Medicine treatment vs antibiotics for recurrent urinary tract infections: a multicenter, randomized controlled study

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Journal of Traditional Chinese Medicine 2024年第3期44卷 524-529页

作者： gu Xiangchen QIU Meisi XIE lin CHEN Min DENG Yueyi ZHANG Changming JIAN guihua WANG Chen WANG Yi Department of Nephrology Yueyang Hospital of Integrated Traditional Chinese and Western Medicine Affiliated to Shanghai University of Traditional Chinese Medicine Department of Nephrology Rizhao Hospital of Traditional Chinese Medicine Department of Nephrology Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Department of Nephrology Shanghai Municipal Traditional Chinese Medicine Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Department of Nephrology the Sixth People's Hospital Affiliated Shanghai Jiaotong University Department of Nephrology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine

OBJECTIVE: To systematically assess the effects of individualized Chinese medicines on recurrent urinary tract infections(rUTIs).METHODS: This study recruited 230 adult female patients in the remission phase of rUTIs from five hospitals in China. The patients were randomly allocated to two groups: an individualized Chinese medicine group(n = 114) and a control group(n = 116). Patients in the Chinese medicine group received individualized Chinese herbs, which were evaluated for syndrome *** in the control group received antibiotic treatment combined with a Chinese medicine placebo. The duration of treatment was three courses of four weeks each, with a three-month subsequent follow-up. UTI recurrence rate,Traditional Chinese Medicine(TCM) syndrome scores,36-item Short Form Survey(SF-36) score, and urine secretory immunoglobulin A(SIgA) were measured and analyzed before and after treatment in each group. RESULTS: Patients from the Chinese medicine group exhibited significant decreases in both short-and longterm UTI recurrence rates compared with the control group(P < 0.05). The changes in TCM syndrome scores between the Chinese medicine and control groups were significant(P < 0.05). The changes in the average SF-36 quality-of-life scores in the Chinese medicine group were also significantly higher than those in the control group after treatment(P < 0.05). The Chinese medicine group also demonstrated a significant increase in urine SIg A expression. CONCLUSION: Taken together, compared to the oftenused long-term antimicrobial prophylaxis during the remission stage of r UTIs, treating patients with an individualized Chinese medicine decoction by syndrome differentiation could effectively reduce the recurrence rate, improve the patients' TCM syndrome scores and quality of life, and enhance immunity, which in turn helps to prevent antibiotic resistance.

关键词： immunoglobulin A, secretory medicine, Chinese traditional quality of life randomized controlled trial syndrome differentiation urinary tract infections

Seasonal Characteristics of Forecasting Uncertainties in Surface PM_(2.5)Concentration Associated with Forecast Lead Time over the Beijing-Tianjin-Hebei Region

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Advances in Atmospheric Sciences 2024年第5期41卷 801-816页

作者： Qiuyan DU Chun ZHAO Jiawang FENG Zining YANG Jiamin XU Jun gu Mingshuai ZHANG Mingyue XU Shengfu lin Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology University of Science and Technology of ChinaHefei 230026China

Forecasting uncertainties among meteorological fields have long been recognized as the main limitation on the accuracy and predictability of air quality ***,the particular impact of meteorological forecasting uncertainties on air quality forecasts specific to different seasons is still not well *** this study,a series of forecasts with different forecast lead times for January,April,July,and October of 2018 are conducted over the Beijing-Tianjin-Hebei(BTH)region and the impacts of meteorological forecasting uncertainties on surface PM_(2.5)concentration forecasts with each lead time are *** increased lead time,the forecasted PM_(2.5)concentrations significantly change and demonstrate obvious seasonal *** general,the forecasting uncertainties in monthly mean surface PM_(2.5)concentrations in the BTH region due to lead time are the largest(80%)in spring,followed by autumn(~50%),summer(~40%),and winter(20%).In winter,the forecasting uncertainties in total surface PM_(2.5)mass due to lead time are mainly due to the uncertainties in PBL heights and hence the PBL mixing of anthropogenic primary *** spring,the forecasting uncertainties are mainly from the impacts of lead time on lower-tropospheric northwesterly winds,thereby further enhancing the condensation production of anthropogenic secondary particles by the long-range transport of natural *** summer,the forecasting uncertainties result mainly from the decrease in dry and wet deposition rates,which are associated with the reduction of near-surface wind speed and precipitation *** autumn,the forecasting uncertainties arise mainly from the change in the transport of remote natural dust and anthropogenic particles,which is associated with changes in the large-scale circulation.

关键词： PM_(2.5) forecasting uncertainties forecast lead time meteorological fields Beijing-Tianjin-Hebei region