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Petroleum Science 2022年第5期19卷 2472-2482页

作者： Xue Xia Chuan-Xian Li Guang-Yu Sun ke-ke zhao Jie Zhang Bo Yao Fei Yang College of Pipeline and Civil Engineering China University of PetroleumQingdaoShandong266580PR China Shandong Provincial key Laboratory of Oil&Gas Storage and Transportation Safety QingdaoShandong266580PR China China Petroleum Engineering&Construction Corp.Beijing Company PR China

Lauramine is widely considered to be an asphaltene flocculant,but its effect on the modification of crude oil by PPDs has been little *** this paper,the effect of LA dosage on the rheology improvement of EVA PPDs(100 ppm)on Qinghai waxy crude oil was investigated through rheological measurement,wax precipitating analysis,granularity test and resins/asphaltenes FTIR *** with pure EVA,the compounding of LA and EVA obviously enhances the agglomeration degree and reduces the number of fine wax crystals,thus further enhancing the rheology of the oil samples,and the best performance is at the LA dosage of 200 *** relatively small LA dosages,the LA facilitates the adsorption of EVA molecules on the asphaltene surfaces,which favors the becoming of EVA/asphaltenes composite particles;but at relatively high LA dosages,the LA makes the asphaltenes more aggregated and disturbs the EVA adsorption on the asphaltenes,which is adverse for the formation of EVA/asphaltenes compound *** compound particles can serve as wax precipitating templates and significantly influence its morphology,thus further improving the crude oil *** consequence,the rheology improvement of EVA PPDs on Qinghai waxy crude oil first increases and then decreases with increasing the LA dosage.

关键词： Waxy crude oil EVA PPD Laurylamine Asphaltenes Synergistic effect

A risk assessment method considering risk attributes and work safety informational needs and its application

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Chinese Journal of Chemical Engineering 2024年第4期68卷 253-262页

作者： Cong Luo Yunsheng zhao ke Xu School of Political Science and Public Administration Shandong UniversityQingdao 266200China Faculty of Engineering China University of GeosciencesWuhan 430074China Department of Emergency Management of Hubei Province Wuhan 430064China

The technological revolution has spawned a new generation of industrial systems,but it has also put forward higher requirements for safety management accuracy,timeliness,and *** assessment needs to evolve to address the existing and future challenges by considering the new demands and advancements in safety *** study aims to propose a systematic and comprehensive risk assessment method to meet the needs of process system safety *** methodology first incorporates possibility,severity,and dynamicity(PSD)to structure the“51X”evaluation indicator system,including the inherent,management,and disturbance risk ***,the four-tier(risk point-unit-enterprise-region)risk assessment(RA)mathematical model has been established to consider supervision *** in conclusion,the application of the PSD-RA method in ammonia refrigeration workshop cases and safety risk monitoring systems is presented to illustrate the feasibility and effectiveness of the proposed PSD-RA method in safety *** findings show that the PSD-RA method can be well integrated with the needs of safety work informatization,which is also helpful for implementing the enterprise's safety work responsibility and the government's safety supervision responsibility.

关键词： Risk assessment Safey “51X”evaluation indicator system Four-tier risk assessment model Risk attributes Process system

Bayesian Filtering for High-Dimensional State-Space Models With State Partition and Error Compensation

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1239-1249页

作者： ke Li Shunyi zhao Biao Huang Fei Liu key Laboratory of Advanced Process Control for Light Industry(Ministry of Education) Institute of AutomationJiangnan UniversityWuxi 214122China Department of Chemical and Materials Engineering University of AlbertaEdmonton AB T6G 2G6Canada

In the era of exponential growth of data availability,the architecture of systems has a trend toward high dimensionality,and directly exploiting holistic information for state inference is not always computationally *** paper proposes a novel Bayesian filtering algorithm that considers algorithmic computational cost and estimation accuracy for high-dimensional linear *** high-dimensional state vector is divided into several blocks to save computation resources by avoiding the calculation of error covariance with immense *** that,two sequential states are estimated simultaneously by introducing an auxiliary variable in the new probability space,mitigating the performance degradation caused by state ***,the computational cost and error covariance of the proposed algorithm are analyzed analytically to show its distinct features compared with several existing *** results illustrate that the proposed Bayesian filtering can maintain a higher estimation accuracy with reasonable computational cost when applied to high-dimensional linear systems.

关键词： filtering estimation error

Smart Contract Vulnerability Detection Method Based on Feature Graph and Multiple Attention Mechanisms

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Computers, Materials & Continua 2024年第5期79卷 3023-3045页

作者： Zhenxiang He Zhenyu zhao ke Chen Yanlin Liu School of Cyber Security Gansu University of Political Science and LawLanzhou730070China

The fast-paced development of blockchain technology is ***,the security concerns of smart contracts represent a significant challenge to the stability and dependability of the entire blockchain *** smart contract vulnerability detection primarily relies on static analysis tools,which are less efficient and *** deep learning methods have improved detection efficiency,they are unable to fully utilize the static relationships within ***,we have adopted the advantages of the above two methods,combining feature extraction mode of tools with deep learning ***,we have constructed corresponding feature extraction mode for different vulnerabilities,which are used to extract feature graphs from the source code of smart ***,the node features in feature graphs are fed into a graph convolutional neural network for training,and the edge features are processed using a method that combines attentionmechanismwith gated ***,the revised node features and edge features are concatenated through amulti-head *** result of the splicing is a global representation of the entire feature *** method was tested on three types of data:Timestamp vulnerabilities,reentrancy vulnerabilities,and access control vulnerabilities,where the F1 score of our method reaches 84.63%,92.55%,and 61.36%.The results indicate that our method surpasses most others in detecting smart contract vulnerabilities.

关键词： Blockchain smart contracts deep learning graph neural networks

Axial enantiomers with donor-regulated TADF feature for multicolor circularly polarized electroluminescence

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Science China Chemistry 2024年第6期67卷 2039-2045页

作者： Chen-Hao Guo Wen-Long zhao ke-ke Tan Wei-Chen Guo Liheng Feng Chuan-Feng Chen Meng Li School of Chemistry and Chemical Engineering Shanxi UniversityTaiyuan030006China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

This study optimized the TADF feature of axial chiral enantiomers through precise donor engineering,and multicolor CP-TADFwas achieved in the axial chiral *** pairs of axial enantiomers with donor-regulated TADF feature,namely(R/S)-TPCBD,(R/S)-DPCBD,and(R/S)-DPACBD,were synthesized by introducing carbazole donors with different substituents onto biphenyl cyanide *** the electron-donating ability of donors increases,the emission of these axial enantiomers ranges from 455,476 to 552 nm,their singlet-triplet energy gaps(ΔE_(ST))gradually decrease from 0.30,0.22 to 0.02 e V,accompanied by an increasement in the transition rate(k_(RISC))of RISC process,and the k_(RISC)of DPACBD could reach up to 7.16×10^(5)s^(-1).These axial enantiomers also exhibit mirror-image CD and circularly polarized luminescence(CPL)***,OLEDs based on TPCBD,DPCBD,and DPACBD as emitter were then fabricated,which displayed blue,green,and orange electroluminescence with EQE_(max)of 13.0%,16.4%,and 25.0%,*** results also exhibited a phenomenon of device efficiency increasing with the enhancement of donor ***,the CP-OLEDs using(R/S)-TPCBD,(R/S)-DPCBD and(R/S)-DPACBD as emitters displayed intense CPEL signals with g_(EL)values of 3.4×10^(-3)/-4.1×10^(-3),3.2×10^(-3)/-3.1×10^(-3)and2.3×10^(-3)/-2.1×10^(-3),*** convenient molecular engineering of donor regulation in the same molecular skeleton,CP-TADF materials with multicolor CPEL and improved device performance could be conveniently achieved.

关键词： axial chirality thermally activated delayed fluorescence circularly polarized luminescence electroluminescence organic light-emitting diodes

Adaptable "bubble particles" prepared by green aqueous phase reshaping for completely removing odor

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Nano Research 2024年第3期17卷 2172-2180页

作者： Jiajia Ma Yichang Xia Tienan zhao Wenfeng Hu Weifeng Zhang Qinfei ke Yi zhao Shanghai Frontiers Science Center of Advanced Textiles Donghua UniversityShanghai 201620China Engineering Research Center of Technical Textiles Ministry of EducationDonghua UniversityShanghai 201620China School of Fashion Engineering Central Laboratory Shanghai University of Engineering ScienceShanghai 201620China Department of Materials Science and Engineering National University of SingaporeSingapore 117575Singapore School of Perfume and Aroma Technology Shanghai Institute of TechnologyShanghai 201418China

Facile and ecofriendly loading of micro/nano function-specific substances to create functional materials is a trend being pursued by ***,current micro/nano particles loading approaches are often hindered by issues such as uneven distribution,unsatisfactory stability and complicate *** this work,we present an aqueous phase reshaping method that only utilizes the moisture to fabricate the"bubble particles",which could perfectly cater to the topography of the *** green preparation of bubble particles adopts an absolutely zero-pollution method,realizing the firm loading of particles on the *** the preparation and loading of particles overcomes the traditional complicate process,while the aqueous phase reshaping ensures uniform and firm loading of the"bubble particles"onto the *** mechanism demonstrates a significant enhancement in the interface relation after aqueous phase reshaping,with a 121-fold increase in contact surface area achieved by reducing the height by 1μ***,we explore for the first time the influence of the nature of the receiving substrate on the interface morphology of particles during electrostatic spraying,which has important guiding significance for the interface relationship of electrostatic spraying and even electrostatic spinning *** also screen out the natural antibacterial essential oil linalool as the effective specialized antibacterial agent,which can specifically inhibit the odor-producing Proteus in urine,with an antibacterial rate of up to 100%.Taken together,this simple,ecofriendly method for fabricating functional materials with optimal interface stability appears highly promising for use in various products formed by electrostatic spraying/spinning.

关键词： bubble particle electrostatic spraying aqueous phase reshaping interface bonding remove odor nano spraying

Artificial intelligence improves accuracy, efficiency, and reliability of a handheld infrared eccentric autorefractor for adult refractometry

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International Journal of Ophthalmology(English edition) 2022年第4期15卷 628-634页

作者： Yi-Ting Cao Dan-Yang Che Yi-Lei Pan Yun-Li Lu Chong-Yang Wang Xiao-Li Zhang Yun-Fei Yang ke-ke zhao Ji-Bo Zhou Department of Ophthalmology Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Shanghai key Laboratory of Orbital Diseases and Ocular Oncology Shanghai 200011China Shanghai MediWorks Precision Instruments Company Limited Shanghai 201112China Department of Ophthalmology Shanghai Children’s Medical CenterShanghai Jiao Tong University School of MedicineShanghai 200127China

AIM: To evaluate the accuracy, efficiency, and reliability of a handheld infrared eccentric autorefractor(h ICA) with artificial intelligence(AI) by comparing its refraction measurements to those recorded using h ICA and a clinical table-mounted automatic refractor(TAR).METHODS: A cross-sectional study using three optometers, including h ICA with or without AI and TAR, for refractometry of adults(aged 19-49 years old) with no signs of ocular disease or trauma in the absence of cycloplegia. Right and left eye refraction data were recorded, including the spherical equivalent(SE), diopter of spherical power(DS), diopter of cylindrical power(DC) decomposed into vectors J0 and J45, and measurement times. To avoid analytical difficulties associated with the interdependence of observations between eyes from the same individual, the Generalized Estimation Equation was used to compare the SE, DS, J0 and J45 measurements, and the times thereof, among the different groups. The intraclass correlation coef f icient(ICC) and Spearman’s rank correlation coefficient were used to evaluate correlations among the measurements recorded by the three different instruments. Bland-Altman were used to analyze the precision of the equipment by the agreement. RESULTS: A total of 70 patients(140 eyes;mean age: 31.37 y;range: 19-49 y) were assessed using refractometry. In a brightly lit environment, there was no significant difference between the mean SE recorded using TAR and that recorded using h ICA with AI or without AI(both P>0.05). In an intense-light environment, h ICA equipped with AI showed a better detection rate than without AI. Light intensity had a greater effect on dioptric measurements recorded using h ICA without AI(P<0.001) than on those recorded using the one equipped with AI(P<0.05). Measurement times varied significantly between the different light intensities and instruments(P<0.05).CONCLUSION: For the normal human eyes, AI may improve the accuracy, efficiency, and reliabil

关键词： dioptric measurement artificial intelligence equipment design infrared eccentric autorefractor

Projecting Wintertime Newly Formed Arctic Sea Ice through Weighting CMIP6 Model Performance and Independence

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Advances in Atmospheric Sciences 2024年第8期41卷 1465-1482页

作者： Jiazhen zhao Shengping HE ke FAN Huijun WANG Fei LI key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway School of Atmospheric Science Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Nansen Environmental and Remote Sensing Center and Bjerknes Centre for Climate Research Bergen 5007Norway Nansen-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China

Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Arctic multiyear sea ice,changes in newly formed sea ice indicate more thermodynamic and dynamic information on Arctic atmosphere–ocean–ice interaction and northern mid–high latitude atmospheric teleconnections. Here, we use a large multimodel ensemble from phase 6 of the Coupled Model Intercomparison Project(CMIP6) to investigate future changes in wintertime newly formed Arctic sea ice. The commonly used model-democracy approach that gives equal weight to each model essentially assumes that all models are independent and equally plausible, which contradicts with the fact that there are large interdependencies in the ensemble and discrepancies in models' performances in reproducing observations. Therefore, instead of using the arithmetic mean of well-performing models or all available models for projections like in previous studies, we employ a newly developed model weighting scheme that weights all models in the ensemble with consideration of their performance and independence to provide more reliable projections. Model democracy leads to evident bias and large intermodel spread in CMIP6 projections of newly formed Arctic sea ice. However, we show that both the bias and the intermodel spread can be effectively reduced by the weighting scheme. Projections from the weighted models indicate that wintertime newly formed Arctic sea ice is likely to increase dramatically until the middle of this century regardless of the emissions ***, it may decrease(or remain stable) if the Arctic warming crosses a threshold(or is extensively constrained).

关键词： wintertime newly formed Arctic sea ice model democracy model weighting scheme model performance model independence

Asymmetric two-dimensional diffraction grating via a vortex field in an inverted-Ytype atomic system

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Communications in Theoretical Physics 2024年第5期76卷 77-85页

作者： Duo Zhang ke Wang Kunpeng zhao Mei Wang zhaoyu Sun School of Electrical and Electronic Engineering Wuhan Polytechnic UniversityWuhan 430023China

We propose a theoretical scheme to realize a two-dimensional(2D)diffraction grating in a four-level inverted-Y-type atomic system coupled by a standing-wave(SW)field and a Laguerre-Gaussian(LG)vortex *** to asymmetric spatial modulation of the LG vortex field,the incident probe field can be lopsidedly diffracted into four domains and an asymmetric 2D electromagnetically induced grating is *** adjusting the detunings of the probe field and the LG vortex field,the intensities of the LG vortex field and the coherent SW field,as well as the interaction length,the diffraction properties and efficiency,can be effectively *** addition,the effect of the azimuthal parameter on the Fraunhofer diffraction of the probe field is also *** asymmetric 2D diffraction grating scheme may provide a versatile platform for designing quantum devices that require asymmetric light transmission.

关键词： asymmetric diffraction grating standing-wave field Laguerre-Gaussian vortex field diffraction property

Aerodynamic/stealth design of S-duct inlet based on discrete adjoint method

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 725-746页

作者： Jun DENG ke zhao Lin ZHOU Wei ZHANG Bowen SHU Jiangtao HUANG Zhenghong GAO School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aerospace Technology Institute of China Aerodynamic Research and Development CenterMianyang 621000Sichuan ProvinceChina

It is a major challenge for the airframe-inlet design of modern combat aircrafts,as the flow and electromagnetic wave propagation in the inlet of stealth aircraft are very *** this study,an aerodynamic/stealth optimization design method for an S-duct inlet is *** upwind scheme is introduced to the aerodynamic adjoint equation to resolve the shock wave and flow *** multilevel fast multipole algorithm(MLFMA)is utilized for the stealth adjoint equation.A dorsal S-duct inlet of flying wing layout is optimized to improve the aerodynamic and stealth *** the aerodynamic and stealth characteristics of the inlet are effectively ***,the optimization results are analyzed,and it shows that the main contradiction between aerodynamic characteristics and stealth characteristics is the centerline and crosssectional *** S-duct is smoothed,and the cross-sectional area is increased to improve the aerodynamic characteristics,while it is completely opposite for the stealth *** radar cross section(RCS)is reduced by phase cancelation for low frequency *** method is suitable for the aerodynamic/stealth design of the aircraft airframe-inlet system.

关键词： S-duct inlet aerodynamic/stealth optimization design discrete adjoint upwind scheme multilevel fast multipole algorithm(MLFMA)