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Analysis of Pseudomomentum Wave-Activity Density in a Heavy Rainfall Event in East China

Atmospheric and Oceanic Science Letters 2014年第1期7卷 42-48页

作者： RAN Ling-Kun hao shou-chang QI Yan-Bin Institute of Atmospheric Physics Chinese Academy of Sciences Shanxi Provincial Meteorological Service Weather Modification Center Chinese Academy of Meteorological Sciences

Taking into account moisture in virtue of general potential temperature,the author derive a three-dimensional(3D) pseudomomentum wave-activity relation for the moist atmosphere from the primitive equations in Cartesian coordinates using the Momentum-Casimir *** the wave-activity relation is constructed in an ageostrophic and non-hydrostatic dynamical framework,it may be applicable to diagnosing the evolution and propagation of mesoscale systems leading to heavy *** theoretical analysis shows that,besides the local change of wave-activity flux divergence and source or sink,the wave-activity relation includes two additional forcing *** first is the zonal gradient of difference between general potential temperature and potential temperature perturbations,and the second is the covariance of the solenoid and gradient of water vapor,denoting the direct influence of moisture on wave-activity *** wave-activity density was applied to a heavy precipitation event occurring in the Jianghuai region of *** calculation showed that the wave-activity density was consistent with 6-h accumulated precipitation observations,in terms of both spatial distribution and temporal *** suggested that the disturbance represented by wave-activity density was closely related to the heavy *** the wave-activity flux divergence and the covariance of the solenoid and gradient of water vapor made the primary contribution to the local change of wave-activity density,the covariance was more *** zonal gradient of difference between general potential temperature and potential temperature perturbations made a weaker contribution to the waveactivity density.

关键词： pseudomomentum wave-activity density wave-activity flux wave-basic flow interaction heavy precipitation event

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MLDA:a multi-level k-degree anonymity scheme on directed social network graphs

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Frontiers of Computer Science 2024年第2期18卷 199-215页

作者： Yuanjing hao Long LI Liang chang Tianlong GU Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin 541004China Engineering Research Center of Trustworthy AI(Ministry of Education) Jinan UniversityGuangzhou 510632China

With the emergence of network-centric data,social network graph publishing is conducive to data analysts to mine the value of social networks,analyze the social behavior of individuals or groups,implement personalized recommendations,and so ***,published social network graphs are often subject to re-identification attacks from adversaries,which results in the leakage of users’***-anonymity technology is widely used in the field of graph publishing,which is quite effective to resist re-identification ***,the current researches still exist some issues to be solved:the protection of directed graphs is less concerned than that of undirected graphs;the protection of graph structure is often ignored while achieving the protection of nodes’identities;the same protection is performed for different users,which doesn’t meet the different privacy requirements of ***,to address the above issues,a multi-level-degree anonymity(MLDA)scheme on directed social network graphs is proposed in this ***,node sets with different importance are divided by the firefly algorithm and constrained connectedness upper approximation,and they are performed different-degree anonymity protection to meet the different privacy requirements of ***,a new graph anonymity method is proposed,which achieves the addition and removal of edges with the help of fake *** addition,to improve the utility of the anonymized graph,a new edge cost criterion is proposed,which is used to select the most appropriate edge to be ***,to protect the community structure of the original graph as much as possible,fake nodes contained in a same community are merged prior to fake nodes contained in different *** results on real datasets show that the newly proposed MLDA scheme is effective to balance the privacy and utility of the anonymized graph.

关键词： directed social network graph graph publishing k-degree anonymity community structure graph utility

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Impact of Annealing on the Melt Recrystallization of a-PDLA/α-PLLA Double-layered Films

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Chinese Journal of Polymer Science 2024年第2期42卷 230-238,I0009页

作者： Yun-Peng Li hao-Ran Shen Shao-Juan Wang hao Zhang Jian Hu Rui Xin Xiao-Li Sun shou-Ke Yan Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plasticsQingdao University of Science&TechnologyQingdao266042China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Poly(lactic acid)(PLA) as a bio-based polymer with biodegradability and biocompatibility has attracted much attention. To manipulate its properties for different applications, regulation of crystal structure and crystalline morphology becomes an attractive research topic. In this work, the structure evolution of layered samples containing an amorphous poly(D-lactide)(PDLA) layer and a crystalline poly(L-lactide)(PLLA)layer with highly oriented edge-on α lamellar crystals after annealing at 150 ℃ or/and after melt-recrystallization has been studied by AFM, FTIR,and TEM combined with electron diffraction. The results demonstrate that melt recrystallization of the as-prepared sample leads to the formation of abundant randomly oriented PLA stereo-complex(PLA SC) crystals. Annealing at 150 ℃ results in the formation of a small amount of oriented PLA SC crystals at the interface. These PLA SC crystals show great impact on the recrystallization behavior of sample after melting at 190 ℃ and then crystallizing at 90 ℃. First, they impede the mutual diffusion of the overlying PDLA and underlying PLLA, and thus reduce their stereocomplexation ability as manifested by the decreased amount of PLA SC crystals. Second, they act as substrate to initiate the epitaxial crystallization of the overlying PDLA and underlying PLLA, which ensures the production of a highly oriented structure of PDLA and PLLA after melt recrystallization again.

关键词： Poly(L-lactide) Poly(D-lactide) Double layer Stereocomplex

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Investigation of multinucleon transfer processes in the Langevin equation model

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-8页

作者： Zou, Ying Zhang, Ming-hao Wang, Mei-Chen Zhang, Yu-Hai Zhang, Feng-shou Beijing Normal Univ Sch Phys & Astron Key Lab Beam Technol Minist Educ Beijing 100875 Peoples R China Beijing Acad Sci & Technol Inst Radiat Technol Beijing 100875 Peoples R China Natl Lab Heavy Ion Accelerator Lanzhou Ctr Theoret Nucl Phys Lanzhou 730000 Peoples R China

Multinucleon transfer in low-energy heavy-ion collisions is increasingly considered a promising approach for generating exotic nuclei. Understanding the complex mechanisms involved in multinucleon transfer processes presents significant challenges for the theoretical investigation of nuclear reactions. A Langevin equation model was developed and employed to investigate multinucleon transfer processes. The 40Ar+232Th\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathrm{{40}Ar} + \mathrm{{232}Th}$$\end{document} reaction was simulated, and the calculated Wilczy & nacute;ski plot was used to verify the model. Additionally, to study the dynamics of multinucleon transfer reactions, the 136Xe+238U\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathrm{{136}Xe} + \mathrm{{238}U}$$\end{document} and 136Xe+209Bi\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mathrm{{136}Xe} + \mathrm{{209}Bi}$$\end{document} reactions were simulated, and the corresponding TKE-mass and angular distributions were computed to analyze the energy dissipation and scattering angles. This investigation enhances our understanding of the dynamics involved in multinucleon transfer processes.

关键词： Reaction mechanisms Multinucleon transfer reactions Langevin equations Wilczy & nacute ski plot Exotic nuclei HEAVY-ION COLLISIONS QUASI-FISSION FUSION DYNAMICS DISSIPATION ISOTOPES NUCLEI ENERGY

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Effect of tubastatin A on NLRP3 inflammasome activation in macrophages under hypoxia/ reoxygenation conditions

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World Journal of Emergency Medicine 2024年第4期15卷 289-296页

作者： hao Li chang Liu Ying Cui Panpan chang Wei Chong Department of Emergency Medicine the First Hospital of China Medical UniversityShenyang 110001China Trauma Medicine Center Peking University People's HospitalBeijing 100871China Key Laboratory of Trauma and Neural Regeneration Peking UniversityBeijing 100871China National Center for Trauma Medicine of China Beijing 100871China

BACKGROUND:There are currently no effective drugs to mitigate the ischemia/reperfusion injury caused by fluid resuscitation after hemorrhagic shock(HS).The aim of this study was to explore the potential of the histone deacetylase 6(HDAC6)-specific inhibitor tubastatin A(TubA)to suppress nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3)inflammasome activation in macrophages under hypoxia/reoxygenation(H/R)***:The viability of RAW264.7 cells subjected to H/R after treatment with different concentrations of TubA was assessed using a cell-counting kit-8(CCK8)***,2.5μmol/L TubA was used with RAW264.7 cells under H/R ***264.7 cells were divided into three groups,namely the control,H/R,and TubA *** levels of reactive oxygen species(ROS)in the cells were detected using fluorescence *** protein expression of HDAC6,heat shock protein 90(Hsp90),inducible nitric oxide synthase(iNOS),NLRP3,gasdermin-D(GSDMD),Caspase-1,GSDMD-N,and Caspase-1 p20 was detected by western *** levels of interleukin-1β(IL-1β)and IL-18 in the supernatants were detected using enzyme-linked immunosorbent assay(ELISA).RESULTS:HDAC6,Hsp90,and iNOS expression levels were significantly higher(P<0.01)in the H/R group than in the control group,but lower in the TubA group than in the H/R group(P<0.05).When comparing the H/R group to the control group,ROS levels were significantly higher(P<0.01),but significantly reduced in the TubA group(P<0.05).The H/R group had higher NLRP3,GSDMD,Caspase-1,GSDMD-N,and Caspase-1 p20 expression levels than the control group(P<0.05),however,the TubA group had significantly lower expression levels than the H/R group(P<0.05).IL-1βand IL-18 levels in the supernatants were significantly higher in the H/R group compared to the control group(P<0.01),but significantly lower in the TubA group compared to the H/R group(P<0.01).CONCLUSION:TubA inhibited the expression of HDAC6,Hsp90,and iNOS in macrophages

关键词： Hemorrhagic shock Hypoxia/reoxygenation Macrophage NLRP3 Tubastatin A

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Possibilities for the synthesis of superheavy element Z=121 in fusion reactions

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Nuclear Science and Techniques 2024年第6期35卷 90-100页

作者： Ming-hao Zhang Yu-Hai Zhang Ying Zou Xiu-Xiu Yang Gen Zhang Feng-shou Zhang The Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental *** synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 *** influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in *** reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section

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Possibility of reaching the predicted center of the“island of stability”via the radioactive beam-induced fusion reactions

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Nuclear Science and Techniques 2024年第9期35卷 186-195页

作者： Ming-hao Zhang Ying Zou Mei-Chen Wang Gen Zhang Qing-Lin Niu Feng-shou Zhang The Key Laboratory of Beam Technology of Ministry of Education School of Physics and AstronomyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of LanzhouLanzhou 730000China

Based on the dinuclear system model,the synthesis of the predicted double-magic nuclei^(298)Fl and 304120 was investigated via neutron-rich radioactive beam-induced fusion *** reaction^(58)Ca+^(244)Pu is predicted to be favorable for producing^(298)Fl with a maximal ER cross section of 0.301 *** of the entrance channel effect reveal that the^(244)Pu target is more promising for synthesizing^(298)Fl than the neutron-rich targets^(248)Cm and^(249)Bk,because of the influence of the Coulomb *** the synthesis of 304120,the maximal ER cross section of 0.046 fb emerges in the reaction^(58)V+^(249)Bk,indicating the need for further advancements in both experimental facilities and reaction mechanisms.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Double-magic nucleus Radioactive beam

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Stage separation of recoverable liquid launch vehicle by using moving pulsating ball analogue for propellant sloshing

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Chinese Journal of Aeronautics 2024年第2期37卷 360-370页

作者： Yu LU Baozeng YUE Bailong hao Bole MA Feng LIU Yuanyuan chang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

In the process of stage separation of recoverable liquid launch vehicles,because of the large amount of residual fuel in the storage tanks,the influence of liquid sloshing on separation safety must be *** calculation simplicity and operation practicability,the Moving Pulsating Ball Model(MPBM)of large amplitude liquid sloshing is introduced into the calculation of launch vehicle stage *** the dynamic equation of the model with the energy relationship during"breathing movement",the formula calculating the force of liquid on the rigid body is *** with the calculations of commercial CFD calculation software,the accuracy of MPBM model is ***,all the external forces and moments are applied to the rigid body of the stages,so that the translational and rotational dynamic equations of the stages are obtained *** to the relative position of the two stages,the geometric shape of the interstage section and the engine of the second stage,the minimum clearance in the separation process can be decided to guarantee that the separation process is safe.

关键词： Moving Pulsating Ball Model(MPBM) Dynamics of stage separation Large amplitude sloshing Recoverable liquid launch vehicle Flight dynamics

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Lubrication condition monitoring of journal bearings in diesel engine based on thermoelectricity

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Friction 2024年第11期12卷 2532-2547页

作者： Yuhao LV hao LIU Zhigang CHEN Weijie chang Hui ZHANG Hulin LI Shanghai Jiao Tong University Shanghai 200240China National Key Laboratory of Marine Engine Science and Technology Shanghai 201108China Shanghai Marine Diesel Engine Research Institute Shanghai 201108China Hunan Aviation Powerplant Research Institute Aero Engine Corporation of ChinaHunan 412002China

There is still a lack of effective lubrication condition monitoring methods in the field of diesel *** paper proposes a novel thermoelectric approach to divide the lubrication state of ***,the generation mechanism of thermoelectric potential on bearings is ***,both experimental and simulation studies are done,and a strong correlation between lubrication and thermoelectric potential is *** film thickness and temperature are further confirmed as significant factors influencing thermoelectric ***,the thermoelectric potential increases with ***,a small film thickness ratio(when the film thickness ratio is less than 4)will suppress the thermoelectric *** typical lubrication states of bearings are distinguished through thermoelectric potential and supported by the Stribeck curve ***,the significant influence of lubrication on the bearing is confirmed through the analysis of surface morphology and composition.

关键词： journal bearing lubrication state,thermoelectric potential condition monitoring

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A hybrid machine learning optimization algorithm for multivariable pore pressure prediction

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Petroleum Science 2024年第1期21卷 535-550页

作者： Song Deng hao-Yu Pan Hai-Ge Wang shou-Kun Xu Xiao-Peng Yan Chao-Wei Li Ming-Guo Peng hao-Ping Peng Lin Shi Meng Cui Fei Zhao School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou213164JiangsuChina Tubular Goods Research Institute of CNPC Beijing102249China CNPC Engineering Technology R&D Company Limited Beijing102206China

Pore pressure is essential data in drilling design,and its accurate prediction is necessary to ensure drilling safety and improve drilling *** methods for predicting pore pressure are limited when forming particular structures and *** this paper,a machine learning algorithm and effective stress theorem are used to establish the transformation model between rock physical parameters and pore *** study collects data from three *** 1 had 881 data sets for model training,and Wells 2 and 3 had 538 and 464 data sets for model *** this paper,support vector machine(SVM),random forest(RF),extreme gradient boosting(XGB),and multilayer perceptron(MLP)are selected as the machine learning algorithms for pore pressure *** addition,this paper uses the grey wolf optimization(GWO)algorithm,particle swarm optimization(PSO)algorithm,sparrow search algorithm(SSA),and bat algorithm(BA)to establish a hybrid machine learning optimization algorithm,and proposes an improved grey wolf optimization(IGWO)*** IGWO-MLP model obtained the minimum root mean square error(RMSE)by using the 5-fold cross-validation method for the training *** the pore pressure data in Well 2 and Well 3,the coefficients of determination(R^(2))of SVM,RF,XGB,and MLP are 0.9930 and 0.9446,0.9943 and 0.9472,0.9945 and 0.9488,0.9949 and *** achieves optimal performance on both training and test data,and the MLP model shows a high degree of *** indicates that the IGWO-MLP is an excellent predictor of pore pressure and can be used to predict pore pressure.

关键词： Pore pressure Grey wolf optimization Multilayer perceptron Effective stress Machine learning

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