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Insect Science 2024年第4期31卷 1150-1164页

作者： Feng Wang Ri-Yuan Wang De-Bin zhong Ping Zhao qing-you Xia Integrative Science Center of Germplasm Creation in Western China(CHONGqing)Science City Biological Science Research CenterSouthwest UniversityChongqingChina Century Legend Biotechnology Research Institute(Chongqing)Co. Ltd.ChongqingChina

Extracellular superoxide dismutase(EcSOD)protects tissues from oxidative stress,and thus is considered as a therapeutic agent for many diseases such as atherosclerosis,hypertension,and ***,cost-effective production of bioactive recombinant human EcSOD(rhEcSOD)remains a ***,we developed an efficient strategy for producing active rhEcSOD by transgenic *** was successfully synthesized as homodimers and homotetramers in the middle silk gland and spun into the cocoons with a concentration of 9.48±0.21 mg/*** of rhEcSOD from the cocoons could be conveniently achieved with a purity of 99.50%and a yield of 3.5±0.5 mg/***,N-glycosylation at the only site of N89 in rhEcSOD with 10 types were *** purified rhEcSOD gained the potent enzymatic activity of 4162±293 U/mg after Cu/Zn ions *** importantly,rhEcSOD was capable of penetrating and accumulating in the nuclei of cells to maintain cell morphology and attenuate ultraviolet B-induced cell apoptosis by eliminating reactive oxygen species and inhibiting the C-Jun N-terminal kinase signaling *** results demonstrated that the transgenic silkworm could successfully produce rhEcSOD with enzymatic and biological activities for biomedical applications.

关键词： antioxidant human extracellular superoxide dismutase recombinant expression silkworm silk gland

Sand control mechanism of radial well filled with phase change material in hydrate reservoir

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Petroleum Science 2024年第4期21卷 2571-2582页

作者： Xiao-Qiang Liu zhong-Xi Han Zhi-Lin Luo Hai-Long Lu Ying Sun qing you Tian-Kui Guo Zhan-qing Qu School of Energy Resources China University of Geosciences (Beijing) Beijing Key Laboratory of Unconventional Natural Gas Geological Evaluation and Development Engineering China University of Geosciences (Beijing) China Research Institute of Petroleum Exploration and Development Engineering Technology Research Institute of Southwest Oil & Gas Field Company PetroChina Beijing International Center for Gas Hydrate School of Earth and Space Sciences Peking University School of Advanced Material Peking University Shenzhen Graduate School School of Petroleum Engineering China University of Petroleum (East China)

Radial well filled with phase change material has been proposed as a novel sand control method for hydrate exploitation. In order to reveal the sand control mechanism, CFD-DEM coupling method is applied to simulate the migration, settlement, and blockage processes of sand particles in the radial *** obtained results indicate that three scenarios have been recognized for sand particles passing through sand control medium, based on the diameter ratio of sand control medium to sand particle（Dd）:fully passing（Dd= 8.75-22.5）, partially passing and partially blocked（Dd= 3.18-5.63）, and completely blocked（Dd= 2.18-3.21）. After being captured by the sand control medium, sand particles can block pores, which increases fluid flow resistance and causes a certain pressure difference in the radial *** pressure in the radial well should be lower than the hydrate phase equilibrium pressure during sand control design, for the purpose of promoting hydrate decomposition, and sand capture. The length of the radial well should be optimized based on the reservoir pore pressure, production pressure difference,bottom hole pressure, and the pressure gradient in the radial well. It should be noticed that the sand control medium leads to a decrease in permeability after sand particles captured. Even the permeability is reduced to several hundred millidarcy, it is still sufficient to ensure the effective flow of gas and water after hydrate decomposition. Increasing fluid velocity reduces the blocking capacity of the sand control medium, mainly because of deterioration in bridging between sand particles.

关键词： Hydrate reservoir Sand control Radial well CFD-DEM

Generic Modeling and Control Framework for Power Systems Dominated by Power Converters Connected Through a Passive Transmission and Distribution Grid

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 292-301页

作者： qing-Chang zhong Marcio Stefanello Department of Electrical and Computer Engineering Illinois Institute of TechnologyChicagoIL 60616USA Syndem LLC USA.M.Stefanello is with the Fundacao Universidade Federal do Pampa at AlegreteRS97546-550Brazil

In this paper,a compact mathematical model having an elegant structure,together with a generic control framework,are proposed for generic power systems dominated by power converters that are interconnected through a passive transmission and distribution(T&D)grid,by adopting the port-Hamiltonian(pH)systems theory and the fundamental circuit *** models of generic T&D lines are developed and then the model of a generic T&D grid is *** the proposed control framework,the controlled converters are proven to be passive and Input-to-State Stable(ISS).The compact mathematical model is scalable and can be applied to power systems with multiple power electronic converters with generic passive controllers,passive local loads,and different types of passive T&D lines connected in a meshed configuration without self-loops,so it is very ***,the resulting power system is proven to be ISS as *** analysis is carried out without assumptions on constant frequency/voltage,constant loads,and/or lossless networks,except the need of passivity for all parts involved,and without using the Clarke/Park transformations or the graph *** simplify the presentation,three-phase balanced systems are adopted but the results can be easily adapted for single-phase or unbalanced three-phase systems.

关键词： Input-to-State Stable(ISS) passivity,portHamiltonian(pH)systems Power electronic converters dominated power systems Synchronized and Democratized(SYNDEM)grid architecture

Market Equilibrium Based on Cloud-edge Collaboration

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 96-104页

作者： Tong Cheng Haiwang zhong qing Xia the State Key Laboratory of Power Systems the Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

Market participants can only bid with lagged information disclosure under the existing market mechanism,which can lead to information asymmetry and irrational market behavior,thus influencing market *** promote rational bidding behavior of market participants and improve market efficiency,a novel electricity market mechanism based on cloudedge collaboration is proposed in this *** market information,called residual demand curve,is published to market participants in real-time on the cloud side,while participants on the edge side are allowed to adjust their bids according to the information disclosure prior to closure *** proposed mechanism can encourage rational bids in an incentive-compatible way through the process of dynamic equilibrium while protecting participants’*** paper further formulates the mathematical model of market equilibrium to simulate the process of each market participant’s strategic bidding behavior towards equilibrium.A case study based on the IEEE 30-bus system shows the proposed market mechanism can effectively guide bidding behavior of market participants,while condensing exchanged information and protecting privacy of participants.

关键词： Cloud-edge collaboration market mechanism residual demand curve strategic bidding

Prediction of contact resistance of electrical contact wear using different machine learning algorithms

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Friction 2024年第6期12卷 1250-1271页

作者： Zhen-bing CAI Chun-lin LI Lei you Xu-dong CHEN Li-ping HE zhong-qing CAO Zhi-nan ZHANG Tribology Research Institute Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

H62 brass material is one of the important materials in the process of electrical energy transmission and signal transmission,and has excellent performance in all *** the wear behavior of electrical contact pairs is particularly complex when they are in service,we evaluated the effects of load,sliding velocity,displacement amplitude,current intensity,and surface roughness on the changes in contact *** learning(ML)algorithms were used to predict the electrical contact performance of different factors after wear to determine the correlation between different factors and contact *** forest(RF),support vector regression(SVR)and BP neural network(BPNN)algorithms were used to establish RF,SVR and BPNN models,respectively,and the experimental data were trained and *** was proved that BP neural network model could better predict the stable mean resistance of H62 brass alloy after *** analysis shows that the load and current have great influence on the predicted electrical contact *** wear behavior of electrical contacts is influenced by factors such as load,sliding speed,displacement amplitude,current intensity,and surface roughness during *** learning algorithms can predict the electrical contact performance after wear caused by these *** results indicate that an increase in load,current,and surface roughness leads to a decrease in stable mean resistance,while an increase in displacement amplitude and frequency results in an increase in stable mean resistance,leading to a decline in electrical contact *** reduce testing time and costs and quickly obtain the electrical contact performance of H62 brass alloy after wear caused by different factors,three algorithms(random forest(RF),support vector regression(SVR),and BP neural network(BPNN))were used to train and test experimental results,resulting in a machine learning model suitable for predicting the stable mean

关键词： electrical contact wear contact resistance machine learning(ML) neural network

Study of deep transportation and plugging performance of deformable gel particles in porous media

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Petroleum Science 2024年第2期21卷 962-973页

作者： Wen-Jing Zhao Jing Wang zhong-Yang Qi Hui-qing Liu National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China

Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before inject

关键词： Physical simulation Deformable gel particle Breakage Particle size Residual resistance coefficient

Microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents during heat treatments

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Rare Metals 2024年第4期43卷 1786-1792页

作者： Yuan-Feng Xie Xing-Cheng Xie zhong-Wu Li Rui-Jun Cao zhong-Kun Lin qing Li Chen-Guang Lin Powder Metallurgy and Special Materials Research Department General Research Institute for Nonferrous MetalsBeijing100088China

The effects of cryogenic treatment(CT)and tempering-cryogenic treatment(TCT)on the microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents were *** binder phase,WC mean grain sizes,W solubility in the binder,relative magnetic s aturation,densities,hardness,wear resistance and second phase precipitation of cemented carbides with different heat treatments were *** results show that there are significant changes of microstructure and properties in the samples with CT and TCT,especially due to the precipitation of metastable nanoparticles W_(x)Co_(y)C_(z) in the binder during the heat treatments of CT and *** the simultaneous combination of microstructure and nanoparticle-reinforced binder,a dramatically improved combination of hardness and wear resistance of the samples after TCT has been achieved.

关键词： Cryogenic treatment Tempering Coarsegrained cemented carbide Carbon content Nanoparticlereinforced binder

Identification and Structures of Two Main Unknown Components in the By-product from the Hydration Synthesis of Camphor

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Chinese Journal of Structural Chemistry 2000年第6期19卷 440-443页

作者： WU Ling LI Zhao-Ji KANG Yao QIN Ye-Yan TANG Yan-Hong YAO Yuan-Gen zhong qing-you LIN Jing-Fu LIN Xiao-qing WANG Zhen-zhong State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matterthe Chinese Academy of SciencesFuzhouFujian 350002 Fujian Wuping Forest Product Chemical Factory WupingFujian 364300 Fujian Wuping Country Science and Technology Bureau WupingFujian 364300

Two main unknown components in the by-product of camphor hydration synthesis were separated and identified by fine fractional distillation and spectroscopic analyses. The components with different ratios of unknown components A and B were collected by the further distillation. The combined spectral results of GC, MS, GC-MS and 13 C NMR of the collected samples revealed that A is exo-2, 2, 3-trimethylbicyclo[2, 2, 1]heptane, and B is endo-2, 2, 3-trimethylbicyclo[2, 2, 1]heptane.

关键词： isolation identification hydration synthesis of camphor

The medium-temperature dependence of jet transport coefficient in high-energy nucleus-nucleus collisions

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Nuclear Science and Techniques 2024年第7期35卷 173-191页

作者： Man Xie qing-Fei Han En-Ke Wang Ben-Wei Zhang Han-zhong Zhang Key Laboratory of Atomic and Subatomic Structure and Quantum Control(MOE) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of MatterInstitute of Quantum Matter South China Normal UniversityGuangzhou510006China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Guangdong Provincial Key Laboratory of Nuclear ScienceSouthern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou 510006China Key Laboratory of Quark and Lepton Physics(MOE)and Institute of Particle Physics Central China Normal UniversityWuhan430079China

The medium-temperature T dependence of the jet transport coefficient̂q was studied via the nuclear modification factor RAA(p_(T))and elliptical flow parameter v_(2)(p_(T))for large transverse momentum p_(T) hadrons in high-energy nucleus-nucleus *** a next-to-leading-order perturbative QCD parton model for hard scatterings with modified fragmentation functions due to jet quenching controlled by q,we check the suppression and azimuthal anisotropy for large p_(T) hadrons,and extract q by global fits to RAA(pT)and v_(2)(pT)data in A+A collisions at RHIC and LHC,*** numerical results from the best fits show that q∕T^(3) goes down with local medium-temperature T in the parton jet *** with the case of a constant q∕T^(3),the going-down T dependence of q∕T^(3) makes a hard parton jet to lose more energy near T_(c) and therefore strengthens the azimuthal anisotropy for large pT *** a result,v_(2)(p_(T))for large pT hadrons was enhanced by approximately 10%to better fit the data at RHIC/*** the first-order phase transition from QGP to the hadron phase and the additional energy loss in the hadron phase,v_(2)(p_(T))is again enhanced by 5-10%at RHIC/LHC.

关键词： Jet quenching Jet transport parameter Hadron suppression Elliptic flow coefficient Energy loss asymmetry

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类鼻疽肺炎26例临床特点与影像学表现

中国现代医学杂志 2014年第19期24卷 88-91页

作者：钟有清林慧海南医学院附属医院呼吸内科海南海口570102 海南省人民医院麻醉科海南海口570311

目的提高人们对类鼻疽肺炎临床特点及影像学表现的认识。方法总结海南岛经培养证实的26例类鼻疽肺炎患者,探讨其临床特点及影像学表现。结果类鼻疽肺炎症状表现为发热(100%)、咳嗽(73.1%)、咳痰(61.5%)等,血常规中性粒细胞比例及C-反应... 详细信息

目的提高人们对类鼻疽肺炎临床特点及影像学表现的认识。方法总结海南岛经培养证实的26例类鼻疽肺炎患者,探讨其临床特点及影像学表现。结果类鼻疽肺炎症状表现为发热(100%)、咳嗽(73.1%)、咳痰(61.5%)等,血常规中性粒细胞比例及C-反应蛋大多明显升高,类鼻疽伯克霍尔德菌血培养阳性占92.3%,痰培养阳性占23.1%。胸部影像学表现常累及上叶为主的多个肺叶,浸润性病变为主(84.6%),结节(46.2%)、胸腔积液(46.2%)、空洞(34.6%)也常见。结论虽未发现特征性改变,但熟悉类鼻疽肺炎临床及影像学表现对该病的诊断还是大有裨益。

关键词：类鼻疽肺炎类鼻疽伯克霍尔德菌放射照像术