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Construction of daily precipitation series and the observational characteristics of extreme precipitation in Tianjin,China during 1888-2022

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Advances in Climate Change Research 2024年第1期15卷 52-61页

作者： peng SI Qing-Xiang LI Xiao-Yang CHEN Min WANG Chuan-jun luo Tianjin Meteorological Information Center Tianjin Meteorological BureauTianjin 300074China Research Centerfor Ecology and Environment of Central Asia Chinese Academy of SciencesWulumuqi 830011China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 528478China Key Laboratory of Tropical Amosphere-Ocean System Ministry of EducationZhuhai 528478China Shaoguan Meteorological Service Shaoguan 512028China

Given the difficulties in rescuing and ensuring the quality of long-term climate data,current studies on century-scale climate change are usually limited to annual and monthly data,resulting in the poor detection of extreme climate events and their changes before *** this study,we reconstructed a daily precipitation series for Tianjin from 15 September 1887 to 31 December 2022 on the basis of the most comprehensive daily precipitation records collected from the Tianjin Meteorological Archive,China,and in reference to the precipitation analysis results based on the datasets developed by the Climatic Research Unit Time-Series version 4.06,Global Precipitation Climatology Centre and University of Delaware along with the application of various homogenisation methods for climate *** approach provides a complete and reliable century-long daily precipitation series for the study of regional or local extreme weather and climate *** reconstructed daily dataset reveals that the annual precipitation amount and R95 intensity in Tianjin during 1888-2022 lack significant trends and have values of 0.74±6.99 and-1.84±3.22 mm per decade,*** the annual and seasonal scales,the precipitation amount and R95 intensity,particularly those in autumn,have increased since the latter half of the 20th century relative to those in ***,the increase in precipitation amount and R95 intensity is relatively limited compared with that in atmospheric water vapour content due to surface warming,indicating the highly sensitive response of extreme precipitation events to *** addition,the estimates for the return periods of 5,10,20,50 and 100 years covering 1888-2022,1888-1950 and 1951-2022 depict that the intensity of heavy rain and above magnitude was highest in 1888-1950 and decreased in 1951-2022.

关键词： Over a century-long timescale Daily precipitation series Extreme precipitation Return period

Glucose-sensitive Membrane with PBA-based Contraction-type Linear Polymer as Chemical Valves Prepared by Surface Grafting

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Chinese Journal of Polymer Science 2024年第8期42卷 1067-1076页

作者： Chun-peng Zhang Si-Jia Gao Ying luo Lei Zou Yong-jun Zhang State Key Laboratory of Separation Membranes and Membrane Processes School of Material Science and EngineeringTiangong UniversityTianjin 300387China State Key Laboratory of Separation Membranes and Membrane Processes School of Pharmaceutical SciencesTiangong UniversityTianjin 300387China Tianjin Key Laboratory of Extracorporeal Life Support for Critical Diseases Institute of Hepatobiliary DiseaseNankai University Affiliated Third Center HospitalTianjin 300170China Cangzhou Institute of Tiangong University Cangzhou 061000China

Glucose-sensitive membrane has potential application in self-regulating insulin *** acid(PBA)is a well-known glucose ***,most PBA-based glucose-sensitive materials are expansion-type,which are not suitable as chemical valves in membrane pores for self-regulating insulin *** to a new glucose-sensitive mechanism,we synthesized PBA-based contraction-type glucose-sensitive liner polymer and ***,a glucose-sensitive membrane was prepared by grafting PBA-based contraction-type glucose-sensitive linear polymer on the membrane *** adjusting the chain length and chain density,the glucose-sensitivity of the membrane was *** membrane can reversibly regulate insulin release at physiologically relevant glucose concentrations in simulates body fluids and fetal bovine *** membrane also has good stability,anti-fouling and biocom *** has potential application in selfregulating insulin release.

关键词： Phenylboronic acid Glucose-sensitive Membrane Surface grafting Insulin

Fretting Wear Behavior of Medium Carbon Steel Modified by Low Temperature Gas Multi-component Thermo-chemical Treatment

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Chinese Journal of Mechanical Engineering 2010年第3期23卷 288-296页

作者： luo jun ZHENG Jianfeng peng Jinfang HE Liping ZHU Minhao Traction Power State Key Laboratory Southwest Jiaotong University Chengdu 610031 China

The introduction of surface engineering is expected to be an effective strategy against fretting damage. A large number of studies show that the low gas multi-component （such as carbon, nitrogen, sulphur and oxygen, etc） thermo-chemical treatment（LTGMTT） can overcome the brittleness of nitriding process, and upgrade the surface hardness and improve the wear resistance and fatigue properties of the work-pieces significantly. However, there are few reports on the anti-fretting properties of the LTGMTT modified layer up to now, which limits the applications of fretting. So this paper discusses the fretting wear behavior of modified layer on the surface of LZ50 （0.48%C） steel prepared by low temperature gas multi-component thermo-chemical treatment （LTGMTT） technology. The fretting wear tests of the modified layer flat specimens and its substrate （LZ50 steel） against 52100 steel balls with diameter of 40 mm are carried out under normal load of 150 N and displacement amplitudes varied from 2 μm to 40 μm. Characterization of the modified layer and dynamic analyses in combination with microscopic examinations were performed through the means of scanning electron microscope（SEM）, optical microscope（OM）, X-ray diffraction（XRD） and surface profilometer. The experimental results showed that the modified layer with a total thickness of 60 μm was consisted of three parts, i.e., loose layer, compound layer and diffusion layer. Compared with the substrate, the range of the mixed fretting regime（MFR） of the LTGMTT modified layer diminished, and the slip regime（SR） of the modified layer shifted to the direction of smaller displacement amplitude. The coefficient of friction（COF） of the modified layer was lower than that of the substrate in the initial stage. For the modified layer, the damage in partial slip regime（PSR） was very slight. The fretting wear mechanism of the modified layer both in MFR and SR was abrasive wear and delamination. The modified layer presented better wear res

关键词： fretting wear fretting regimes low temperature gas multi-component thermo-chemical treatment(LTGMTT) modified layer medium carbon steel

Universal paradigm of ternary metacomposites with tunable epsilon-negative and epsilon-near-zero response for perfect electromagnetic shielding

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Rare Metals 2024年第2期43卷 796-809页

作者： Yun-peng Qu Yun-Lei Zhou Yang luo Yao Liu jun-Fei Ding Yan-Li Chen Xiu Gong Jing-Liang Yang Qiong peng Xiao-Si Qi College of Physics Guizhou UniversityGuiyang550025China Hangzhou Institute of Technology Xidian UniversityHangzhou311231China Department of Materials ETH Zurich8093ZurichSwitzerland Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan250061China

CaCu_(3)Ti_(4)O_(12)(CCTO)ceramic nanocomposites incorporating graphene–carbon black(GRCB)fillers were fabricated by spark plasma sintering *** percolative effects of conductive GRCB fillers on dielectric response of GRCB/CCTO ternary metacomposites were systematically *** weakly real permittivity(ε′)-negative response(ε′~−1×10^(2))was achieved which originated from weakly low-frequency plasmonic state of free carriers within constructed GRCB *** enhancing three-dimensional GRCB network,the plasma frequency of metacomposites increased while the damping factor ***,theε′-negative values of metacomposites were tuned from−10^(2) to−10^(4) orders of magnitude andε′-near-zero(ENZ)frequencies from~142 to~340 MHz which substantially benefited from the moderate carrier concentration of GRCB dual *** Drude model and equivalent circuit models were adopted to demonstrate dielectric and electrical *** obtained metacomposites show strong EM shielding effect along with enhanced plasmonic oscillation and even better achieving perfect EM shielding effect in ENZ *** work achieves the tunableε′-negative andε′-near-zero response and more importantly clarifies its regulation mechanism in ceramic-based ternary metacomposites,which opens up the possibility of designing high-performance EM shielding materials based on metacomposites.

关键词： Metacomposites Ceramic matrix composites Negative permittivity Epsilon-near-zero Electromagnetic shielding

Advanced rare earth tantalate RETaO_(4)(RE=Dy,Gd and Sm) with excellent oxygen/thermal barrier performance

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Journal of Rare Earths 2024年第8期42卷 1595-1603,I0007页

作者： jun Wang Jianyu Li Chunyu Jiang Jianbo Song Xing Yang Xiaolong Ma Kailiang luo peng Wu Xiaoyu Chong Jing Feng Faculty of Material Science and Engineering Kunming University of Science and TechnologyKunming650093China Shanxi Tianxuan Coating Technology Co. LtdXi'an710000China

Thermal barrier coatings(TBCs) materials with lowered the rmal and oxygen ion conductivity can provide thermal and oxidative protection for high te mperature hot-end components in aero nautical engines and gas turbines,The rare-earth tantalate RETaO_(4)(RE=Dy,Gd and Sm) ceramics with monoclinic(m) phase were successfully synthesized via spark plasma *** vacancies responsible for the thermal and oxygen ion conductivities of RETaO_(4) were demonstrated by atomic-resolution energy dispersive Xray and X-ray photoelectron *** the three samples,DyTaO_(4) has excellent oxygen/thermal barrier *** to the current service thermal barrier coating material ZrO_(2)-8 wt% Y_(2)O_(3)(8 YSZ),DyTaO_(4) has an ultra-low oxygen ion conductivity benefiting from low oxygen vacancy concentration and strong stretching force *** intrinsic thermal conductivity of DyTaO_(4)is 68.2% less than that of 8 ***,the thermal expansion rate curves indicate that the phase transformation does not happen from room te mperature to 1200℃.The above results demonstrate that high-growth rate the rmally grown oxide can be retarded by creating dense DyTaO_(4) coating with lowered thermal and oxygen ion conductivity.

关键词： Thermal barrier coatings Rare earths Oxygen vacancies Thermal conductivity Oxygen ion conductivity

A Simple Proof of ACC for Minimal Log Discrepancies for Surfaces

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Acta Mathematica Sinica,English Series 2024年第2期40卷 425-434页

作者： Jing jun HAN Yu Jie luo Shanghai Center for Mathematical Sciences Fudan UniversityJiangwan CampusShanghai 200438P.R.China Department of Mathematics Johns Hopkins UniversityBaltimoreMD 21218USA

Following Shokurov's idea,we give a simple proof of the ACC conjecture for minimal log discrepancies for surfaces.

关键词： Ascending chain condition minimal log discrepancies minimal model program surface

The governance technology for blockchain systems:a survey

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Frontiers of Computer Science 2024年第2期18卷 181-197页

作者： Guocheng ZHU Debiao HE Haoyang AN Min luo Cong peng School of Cyber Science and Engineering Wuhan UniversityWuhan 430072China Shandong Provincial Key Laboratory of Computer Networks Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014China

After the Ethereum DAO attack in 2016,which resulted in significant economic losses,blockchain governance has become a prominent research ***,there is a lack of comprehensive and systematic literature review on blockchain *** deeply understand the process of blockchain governance and provide guidance for the future design of the blockchain governance model,we provide an in-depth review of blockchain *** this paper,first we introduce the consensus algorithms currently used in blockchain and relate them to governance ***,we present the main content of off-chain governance and investigate two well-known off-chain governance ***,we investigate four common on-chain governance voting techniques,then summarize the seven attributes that the on-chain governance voting process should meet,and finally analyze four well-known on-chain governance blockchain projects based on the previous *** hope this survey will provide an in-depth insight into the potential development direction of blockchain governance and device future research agenda.

关键词： blockchain governance off-chain governance on-chain governance voting

Cross-Dimension Attentive Feature Fusion Network for Unsupervised Time-Series Anomaly Detection

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3011-3027页

作者： Rui Wang Yao Zhou Guangchun luo peng Chen Dezhong peng School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China School of Computer and Software Engineering Xihua UniversityChengdu610039China School of Computer Science Sichuan UniversityChengdu610065China National Innovation Center for UHD Video Technology Chengdu610095China

Time series anomaly detection is crucial in various industrial applications to identify unusual behaviors within the time series *** to the challenges associated with annotating anomaly events,time series reconstruction has become a prevalent approach for unsupervised anomaly ***,effectively learning representations and achieving accurate detection results remain challenging due to the intricate temporal patterns and dependencies in real-world time *** this paper,we propose a cross-dimension attentive feature fusion network for time series anomaly detection,referred to as ***,a series and feature mixing block is introduced to learn representations in 1D ***,a fast Fourier transform is employed to convert the time series into 2D space,providing the capability for 2D feature ***,a cross-dimension attentive feature fusion mechanism is designed that adaptively integrates features across different dimensions for anomaly *** results on real-world time series datasets demonstrate that CAFFN performs better than other competing methods in time series anomaly detection.

关键词： Time series anomaly detection unsupervised feature learning feature fusion

Progress in research on the exploration and evaluation of deep geothermal resources in the Fujian-Guangdong-Hainan region,China

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Energy Geoscience 2024年第2期5卷 1-13页

作者： Herong Zheng jun luo Petroleum Exploration and Production Research Institute SINOPECBeijing 102206China

Deep geothermal resources in the Fujian-Guangdong-Hainan region,China,offer significant potential for sustainable *** diverse igneous rock formations along the southeast coast present intricate geological challenges that impede exploration and evaluation *** this study,we address critical concerns related to the Fujian-Guangdong-Hainan region's deep geothermal resources,encompassing heat source composition,formation conditions,strategic favorable areas,and exploration *** methods involve the analysis of regional geothermal reservoirs and cap *** findings include:the primary heat sources in the Fujian-Guangdong-Hainan region consist of the radioactive heat generation from granites in the crust,heat conduction in the mantle,and,in specific areas like Yangjiang and Shantou,melts within the middle and lower crust;the deep,high-temperature geothermal resources in the region predominantly reside in basins'depressed *** areas are characterized by the confluence of triple heat sources:heat from the Earth's crust,mantle,and other supplementary sources;our analysis led to the identification of three strategic areas favorable for deep geothermal resources in the Fujian-Guangdong-Hainan *** are the Beibu Gulf Basin's continental area,the Yuezhong Depression,and the Fuzhou-Zhangzhou area.

关键词： Deep geothermal resources Geology of geothermal energy Strategic selection