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Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： liang-liang Dong Yu-Lin Zhang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. The separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable *** structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. The simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. The composite AICD is suitable for the entire stage of horizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

Non-interactive SM2 threshold signature scheme with identifiable abort

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Frontiers of Computer Science 2024年第1期18卷 171-185页

作者： Huiqiang liang Jianhua CHEN School of Mathematics and Statistics Wuhan UniversityWuhan 430072China

A threshold signature is a special digital signature in which the N-signer share the private key x and can construct a valid signature for any subset of the included t-signer,but less than t-signer cannot obtain any *** the breakthrough achievements of threshold ECDSA signature and threshold Schnorr signature,the existing threshold SM2 signature is still limited to two parties or based on the honest majority setting,there is no more effective solution for the multiparty *** make the SM2 signature have more flexible application scenarios,promote the application of the SM2 signature scheme in the blockchain system and secure cryptocurrency *** paper designs a non-interactive threshold SM2signature schemebasedon partially homomorphic encryption and zero-knowledge *** the last round requires the message input,so make our scheme non-interactive,and the pre-signing process takes 2 rounds of communication to complete after the key *** allow arbitrary threshold t

关键词： SM2 signature secure multi-party computation threshold signature UC-secure dishonest majority

64 Gb/s low-voltage waveguide SiGe avalanche photodiodes with distributed Bragg reflectors

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Photonics Research 2020年第7期8卷 1118-1123页

作者： Binhao Wang Zhihong Huang Yuan Yuan di liang Xiaoge Zeng Marco Fiorentino Raymond G.Beausoleil Hewlett Packard Laboratories Hewlett Packard EnterprisePalo AltoCalifornia 94304USA

We demonstrate low-voltage waveguide silicon-germanium avalanche photodiodes(APDs)integrated with distributed Bragg reflectors(DBRs).The internal quantum efficiency is improved from 60%to 90%at 1550 nm assisted with DBRs while still achieving a 25 GHz bandwidth.A low breakdown voltage of 10 V and a gain bandwidth product of near 500 GHz are *** with DBRs at a data rate of 64 Gb/s pulse amplitude modulation with four levels(PAM4)show a 30%–40%increase in optical modulation amplitude(OMA)compared to APDs with no DBR.A sensitivity of around-13 d Bm at a data rate of 64 Gb/s PAM4 and a bit error rate of 2.4×10^-4 is realized for APDs with DBRs,which improves the sensitivity by^2 d B compared to APDs with no DBR.

关键词： Gb/s waveguide avalanche

Comparative Effectiveness of Mobile Health-Based Comprehensive Smoking Cessation Modalities and Traditional Clinic-Delivered Treatments—Beijing Municipality,China,May 2022 to April 2024

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China CDC weekly 2024年第22期6卷 516-521页

作者： Shuilian Chu Hang Jing di Zhang Yuan Cao Yunliang Qian Xiurong Liu Lin Xiao Zhaohui Tong Lirong liang Department of Research on Tobacco Dependence Therapies Beijing Institute of Respiratory Medicine and Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina Beijing Center for disease Prevention and Control BeijingChina Tobacco Control Office Chinese Center for Disease Control and PreventionBeijingChina Department of Respiratory and Critical Care Medicine Beijing Institute of Respiratory Medicine and Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina

What is already known about this topic?Most Chinese smokers have not accessed professional help due to a lack of sufficient smoking cessation *** health(mHealth)can mitigate obstacles related to time and transportation,thereby providing effective support for smokers seeking to *** is added by this report?This study offers real-world evidence supporting the effectiveness of mHealth-based comprehensive smoking cessation *** findings indicate that these modalities can significantly enhance abstinence rates,albeit to a lesser extent compared to traditional clinicbased *** to the intervention was identified as a critical factor influencing the effectiveness of smoking cessation *** are the implications for public health practice?The mHealth-based comprehensive smoking cessation modalities,with or without mailing cessation medications,present a promising approach to enhancing access to and utilization of smoking cessation *** strategy addresses the significant challenge of limited smoking cessation resources in China.

关键词： smoke Health thereby

Analysis of the urinary peptidome associated with Helicobacter pylori infection

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World Journal of Gastroenterology 2011年第5期17卷 618-624页

作者： di Xiao Fan-liang Meng Li-Hua He Yi-Xin Gu Jian-Zhong Zhang National Institute for Communicable disease Controland Prevention Chinese Center for Disease Control and Pre-vention Beijing 102206 China

AIM： To investigate the relationship between urinary peptide changes and Helicobacter pylori （H. pylorl） infection using urinary peptidome profiling. METHODS： The study was performed in volunteers （n = 137） who gave informed consent. Urinary peptides were enriched by magnetic beads based weak cation exchange chromatography＇and spectrums acquired by matrix-assisted laser desorption/ionization time-of-flight （MALdi-TOF） mass spectrometry （MS）. ClinProTools bioinformatics software was used for statistical analysis and the recognition of peptide patterns. The marker peptides were identified by LTQ Obitrap XL tandem MS. RESULTS： Approximately 50 proteins or peptides which loaded onto the magnetic beads were detected by MAL-di-TOF MS. By optimizing the parameters of the model, the Genetic Algorithm model had good recognition capability （97%） and positive predictive value （94%）. Based on the model, 2 markers with molecular masses of 6788 and 1912 Da were found that differentiated between H. pylori positive and negative volunteers. The m/z 1912 sequence was parsed as SKQFTSSTSYN- RGDSTF. The peptide was identified as isoform 1 of the fibrinogen a chain precursor, whose concentration in urine was markedly higher in H. pylori infected volunteers than in H. pylori non-infected ones. CONCLUSION： The appearance of urinary fibrinogen degradation products is caused by an active H. pyloriinduced process.

关键词： Urinary peptidome profiling MB-matrix-assisted laser desorption/ionization time-of-flight massspectrometry Helicobacter pylori Fibrinogen degrada-tion products

Silicon-plus photonics

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Frontiers of Optoelectronics 2016年第3期9卷 436-449页

作者： Daoxin DAI Yanlong YIN Longhai YU Hao WU di liang Zhechao WANG Liu LIU Centre for Optical and Electromagnetic Research State Key Laboratory for Modem Optical Instrumentation Zhejiang University Hangzhou 310058 China System Research Lab Hewlett Packard labs Palo Alto CA USA Center for Nano- and Biophotonics (NB-Photonics) Ghent University Sint-Pietersnieuwstraat 41 Ghent 9000 Belgium SCNU-ZJU Joint Research Center of Photonics Centre for Optical and Electromagnetic Research South China Academy of Advanced Optoelectronics South China Normal University Guangzhou 510006 China

Silicon photonics has become very popular because of their compatibility with mature CMOS technologies. However, pure silicon is still very difficult to be utilized to obtain various photonic functional devices for large-scale photonic integration due to intrinsic properties. Silicon-plus photonics, which pluses other materials to break the limitation of silicon, is playing a very important role currently and in the future. In this paper, we give a review and discussion on the progresses of siliconplus photonics, including the structures, devices and applications.

关键词： silicon-plus hybrid plsamonic photodetector modulator graphene,Ⅲ-Ⅴ

Theoretical and experimental investigations on single-atom catalysis:Pt1/FeOx for water-gas shift reaction Shan-Fei Wang1,§,Yangyang Li2,3,§,Haiyan Wang1,Jin-Xia liang1(✉),Chun Zhu1

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Nano Research 2024年第9期17卷 8627-8637页

作者： Shan-Fei Wang Yangyang Li Haiyan Wang Jin-Xia liang Chun Zhu Botao Qiao School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Oxide-supported metal single-atom catalysts(SACs)have exhibited excellent catalytic performance for water-gas shift(WGS)***,we report the single-atom catalyst Pt1/FeOx exhibits excellent medium temperature catalytic performance for WGS reactions by the density functional theory(DFT)calculations and experimental *** calculations indicate that H_(2)O molecules are easily dissociated at oxygen vacancies,and the formed*OH and*O are adsorbed on Pt1 single atoms and the adjacent O atoms,*** studying four possible reaction mechanisms,it is found that the optimal WGS reaction pathway is proceeded along the carboxyl mechanism(pathway III),in which the formation of*COOH intermediates can promote the stability of Pt1/FeOx SAC and the easier occurrence of WGS *** energy barrier of the rate-determining step during the entire reaction cycle is only 1.16 eV,showing the high activity for the medium temperature WGS reaction on Pt1/FeOx SAC,which was verified by experimental ***,the calculated turnover frequencies(TOFs)of CO_(2)and H_(2)formation on Pt1/FeOx at 610 K(337℃)can reach up to 1.14×10^(-3)s^(-1)·site^(-1)through carboxyl *** this work,we further expand the application potential of Pt1/FeOx SAC in WGS reaction.

关键词： water-gas shift(WGS)reaction single-atom catalyst(SAC) density functional theory(DFT) thermocatalysis

Geometrical transition properties of vortex cavitation and associated flow-choking characteristics in poppet valves

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期25卷 455-469页

作者： liang LU Zhongdong liang Yuming LIU Zhipeng WANG Shohei RYU School of Mechanical Engineering Tongji UniversityShanghai 201804China Frontiers Science Center for Intelligent Autonomous Systems Tongji UniversityShanghai 201210China Technical Research Laboratory Hitachi Construction Machinery Co.Ltd.Tsuchiura 300-0013Japan

Poppet valves have become increasingly significant in ensuring precise digital flow rate and pressure control in hydraulic systems,necessitating a more profound understanding of the geometrical properties of cavitation in them,as well as associated flow-choking *** a comparative analysis with experimentally observed cavity images,we found that large eddy simulation(LES)turbulence modeling effectively replicates the geometrical properties of cavitation in these *** analysis demonstrated that cavitation is generated from vortices that result from the interaction between the notch contracta flow and the surrounding fluid *** in the internal or external vena contracta conditions result in fixed or discrete cavities,and the length-to-diameter ratio serves as a measure of the transition between internal and external vena contracta flow *** study establishes a threshold length-to-diameter ratio of approximately 2 for the tested poppet *** specifically,in notch structures with a smaller valve opening,longer sealing length,and smaller throttling angle(corresponding to a larger length-to-diameter ratio),the liquid-to-vapor transfer process is more evident than that in the reverse direction.A long-standing vapor cavity becomes fixed inside the notch,leading to a more pronounced flow-choking *** contrast,for structures with a smaller length-to-diameter ratio,the cavitation process for discrete vapor cavities is more complete,ensuring fluid flow continuity and significantly reducing the occurrence of the flow-choking phenomenon.

关键词： Poppet valves Vena contracta Vortex flow Vapor cavity Flow-choking

基于城市化梯度的广州市蝴蝶群落结构及其物种多样性分析

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福建农业科技 2024年第5期55卷 49-54页

作者：孙双双叶蓁罗海林黄春荣许睿钟志强李宇盘凯筠梁迪文生态环境部华南环境科学研究所/国家环境保护城市生态环境模拟与保护重点实验室广东广州510655

蝴蝶是城市化对生物多样性影响评价的重要指示物种,为了探究广州市蝴蝶群落多样性与生境类型、城市化之间的关系。2023年按照城市化梯度,选取0~2000、2000~4000、10000 m以外范围的6条样线,并按照样线内植被类型将其划分为近自然植物群... 详细信息

蝴蝶是城市化对生物多样性影响评价的重要指示物种,为了探究广州市蝴蝶群落多样性与生境类型、城市化之间的关系。2023年按照城市化梯度,选取0~2000、2000~4000、10000 m以外范围的6条样线,并按照样线内植被类型将其划分为近自然植物群落及人工植物群落,采用样线调查法对蝴蝶的种类和数量进行调查并统计分析。结果表明:6条样线共调查蝴蝶8科32属45种,优势种为矍眼蝶Ypthima balda;研究区域内蝴蝶Margalef种类丰富度指数、Shannon-Wiener指数、Simpson指数、Pielou物种均匀度指数、Simpson优势度指数均为近自然植物群落样线>人工植物群落样线;蝴蝶群落特征中科属种的数量、Margalef种类丰富度指数、Simpson优势度指数、Shannon-Wiene指数及Simpson指数均与距城市中心距离呈正相关关系,与可达方式呈负相关关系;Pielou均匀度指数与距城市中心距离呈负相关关系而与可达方式呈正相关关系;蝴蝶属的数量及Shannon-Wiene指数受人为活动影响较为明显。由此可见生境类型和人类活动对蝴蝶物种分布具有重要影响,且城市化对广州市蝴蝶多样性具有较为显著的影响。

关键词：城市化蝴蝶多样性