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Petroleum Science 2022年第2期19卷 678-687页

作者： Guo-Shuai Ju Tie Yan xiao-Feng Sun Jing-Yu qu Qiao-bo Hu College of Petroleum Engineering Northeast Petroleum UniversityDaqing163318HeilongjiangPeople's Republic of China

With ongoing development of oil exploration and techniques,there is a significant need for improved well control strategies and formation pressure prediction *** this paper,a gas-liquid transient drift flow model was established according to the gas-liquid two-phase flow characteristics during the gas kick.A Roe scheme was used for numerical calculation based on the finite volume *** changes of bottom-hole pressure,casing pressure,the development law of cross-sectional gas holdup,and gas velocity,along with the vertical well depth,were analyzed through simulation *** time-series characteristics of mud pit gain were obtained by adjusting the formation *** complex nonlinear mapping relationship between the formation parameters and the mud pit gain was *** long short-term memory network(LSTM)of deep learning was used to obtain a formation pressure inversion when the blowout is out of control and the well cannot be *** data from a well were used to verify the gas-liquid two-phase transient drift flow model based on the finite volume method,demonstrating that this method is reliable,with greatly improved prediction *** approach provides theoretical support for the early monitoring of gas kick during drilling,and for well-killing design and construction after uncontrolled blowout.

关键词： Gas kick Formation pressure Multiphase flow Computational model Long short-term memory

椎体骨皮质强化差异对骨质疏松性椎体压缩性骨折生物力学的影响

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中国组织工程研究 2025年第21期29卷 4430-4438页

作者：方伟黄兴桦屈波杨红胜重庆市云阳县中医院骨伤科重庆市404500 成都医学院附属第一医院骨科四川省成都市610500

背景:骨质疏松性椎体压缩性骨折经皮椎体成形过程中骨水泥在椎体内的骨皮质强化区域对脊柱生物力学及临床疗效有重要影响,但以往研究大多局限于二维层面。目的:采用有限元分析法探讨经皮椎体成形过程中骨水泥在椎体三维层面内骨皮质强... 详细信息

背景:骨质疏松性椎体压缩性骨折经皮椎体成形过程中骨水泥在椎体内的骨皮质强化区域对脊柱生物力学及临床疗效有重要影响,但以往研究大多局限于二维层面。目的:采用有限元分析法探讨经皮椎体成形过程中骨水泥在椎体三维层面内骨皮质强化差异对骨质疏松性椎体压缩性骨折椎体、邻近椎间盘及终板生物力学分布的影响,以评估其效果。方法:建立T12椎体骨质疏松性压缩性骨折行经皮椎体成形治疗的有限元模型,从横断面、矢状面、冠状面对骨水泥有无皮质强化情况进行分组分析,研究不同体位变化下,骨皮质强化对T12椎体松质骨、皮质骨、T11/T12椎间盘、T12/L1椎间盘、T11下终板、L1上终板生物力学的影响。结果与结论:(1)在垂直压缩力作用下,经皮椎体成形过程中有或无骨水泥皮质强化在不同体位变化下除伤椎皮质骨以外结构应力变化均不明显;(2)伤椎皮质骨Von Mises应力值在人体前屈、左/右侧弯和左/右轴向旋转时差异显著,同一平面内骨皮质完全强化组较无骨皮质强化组最大Von Mises应力值明显变小,随着骨皮质强化越广泛Von Mises应力值整体呈下降趋势;(3)提示行经皮椎体成形治疗时,横断面内骨水泥应尽量广泛对称水平分布于椎体骨皮质边缘,矢状面内骨水泥应广泛纵向分布且靠近上下终板及前后壁,冠状面内骨水泥应广泛分布于中线两侧同时对称接触上下终板及侧壁,可有效避免伤椎再骨折风险且不增加邻椎骨折、残留盘源性疼痛风险。

关键词：经皮椎体成形骨皮质强化骨质疏松性椎体压缩性骨折邻近椎间盘终板三维有限元分析生物力学

Continuum Skyrme Hartree-Fock-bogoliubov theory with Green’s function method for neutron-rich Ca,Ni,Zr,and Sn isotopes

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Nuclear Science and Techniques 2023年第7期34卷 162-178页

作者： En-bo Huo Ke-Ran Li xiao-Ying qu Ying Zhang Ting-Ting Sun School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China School of Mechatronics Engineering Guizhou Minzu UniversityGuiyang 550025China Department of Physics School of ScienceTianjin UniversityTianjin 300072China Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology Guangxi Normal UniversityGuilin 541004China

The possible exotic nuclear properties in the neutron-rich Ca,Ni,Zr,and Sn isotopes are examined with the continuum Skyrme Hartree-Fock-bogoliubov theory in the framework of the Green’s function *** pairing correlation,the couplings with the continuum,and the blocking effects for the unpaired nucleon in odd-A nuclei are properly *** Skyrme interaction SLy4 is adopted for the ph channel and the density-dependentinteraction is adopted for the pp chan-nel,which well reproduce the experimental two-neutron separation energies S_(2n)and one-neutron separation energies *** is found that the criterion S_(n)>0 predicts a neutron drip line with neutron numbers much smaller than those for S_(2n)>*** to the unpaired odd neutron,the neutron pairing energies−E_(pair)in odd-A nuclei are much lower than those in the neighbor-ing even-even *** investigating the single-particle structures,the possible halo structures in the neutron-rich Ca,Ni,and Sn isotopes are predicted,where sharp increases in the root-mean-square(rms)radii with significant deviations from the traditional rA^(1∕3)rule and diffuse spatial density distributions are *** the contributions of various partial waves to the total neutron densityρlj(r)∕ρ(r)reveals that the orbitals located around the Fermi surface-particularly those with small angular momenta-significantly affect the extended nuclear density and large rms *** number of neutrons Nλ(N_(0))occupying above the Fermi surfacen(continuum threshold)is discussed,whose evolution as a function of the mass number A in each isotope is consistent with that of the pairing energy,supporting the key role of the pairing correlation in halo phenomena.

关键词： Neutron-rich nuclei Neutron halo Skyrme Hartree-Fock-bogoliubov theory Green’s function method

Analysis of Seasonal Differences of Chlorophyll,Dimethylsulfide,and Ice Between the Greenland Sea and the Barents Sea

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Journal of Ocean University of China 2023年第6期22卷 1592-1604页

作者： ZHONG Guangsheng qu bo School of Science Nantong University226019China

Arctic Ocean(AO)climate is closely related to sea ice concentration(ICE)and chlorophyll_a(CHL)*** 2003–2014,the spatial average concentrations of CHL,ICE,sea surface temperature(SST),wind speed(WIND)in the Greenland Sea region(GS)(20˚W–10˚E,70˚–80˚N)and the Barents Sea region(BS)(30˚–50˚E,70˚–80˚N)are analysed and *** CHL was observed in BS,about 60%higher than that in *** with the northern regions of BS and GS(BSN and GSN),CHL in the southern region of BS and GS(BSS and GSS)increased by 77%and 42%*** ice melting in BSN is the main reason for phytoplankton *** 2010,there was an unusual peak of CHL concentration in *** sea-sonal peaks of CHL appeared two weeks earlier in BS than in *** earlier and more extensive ice melting and the persistent nega-tive North Atlantic Oscillation(NAO)index may be the reasons for higher CHL blooms in *** spatial average ICE concentra-tion of BS in BSN and BSS is 27%and 1.2%*** NAO in the previous winter may lead to an increase in ICE in *** has a great influence on CHL and ICE in *** melting is positively correlated with CHL,especially in GS in recent decades,CHL has a significant positive correlation with surface mass concentration of dimethylsulfide(DMS),especially in *** an indicator of Arctic warming,BS needs more attention from Arctic researchers.

关键词： dimethylsulfide chlorophyll ice North Atlantic Oscillation Arctic

Vertical Chlorophyll and Dimethylsulfide Profile Simulations in Southern Greenland Sea

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Journal of Ocean University of China 2022年第6期21卷 1565-1574页

作者： qu bo SUN Wenjing School of Science Nantong UniversityNantong 226007China YK Pao School Middle School CampusShanghai 200336China

Biogenetic sulfide dimethylsulfide(DMS)plays a major role on the global climate,especially in Arctic *** simulate DMS concentration is an important *** we introduced both biogeochemical depth-averaged model G93 and its extension model-one dimensional DMS *** surface concentrations,vertical profiles of chlorophyll(CHL)and DMS are simulated using the two models within southern Greenland Sea(0°E–10°E,70°N–75°N)during year *** the input data for the models simulations,the spatial monthly mean of methodology forcings including sea surface temperature(SST),wind speed(WIND),cloud cover(CLD),sea ice concentration(ICE)and mixed layer depth(MLD)are *** 8-day time series of chlorophyll-a(CHL)are used as observation data for CHL related parameter ***ó’s imperial formula is used as the monthly DMS observation *** Genetic Algorithm technique is used for the parameter *** simulation results show that the most DMS related surface concentrations exhibit the normal distributions with peak during ***,DMS and DMSP(dimethylsulphoniopropionate)vertical profiles are obtained for July,August and September in year *** had the higher variation of subsurface concentration maximum(SCM)in July with the lower surface concentration *** had surface higher and subsurface lower profile for the all three *** also had subsurface high in *** SCM CHL diurnal variation in the subsurface also can be resulted from diurnal changes in MLD and vertical mixing variations,plus photolysis and wind-driven ventilations.

关键词： dimethylsulfide vertical profile chlorophyll biogeochemical modeling Greenland Sea

Microstructure and thermal properties of copper matrix composites reinforced with titanium-coated graphite fibers

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Rare Metals 2013年第1期32卷 75-80页

作者： Hao-Ming Zhang Xin-bo He Xuan-Hui qu Qian Liu xiao-Yu Shen School of Materials Science and Engineering University of Science and Technology Beijing State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

Milled form of mesophase pitch-based graphite fibers were coated with a titanium layer using chemical vapor deposition technique and Ti-coated graphite fiber/Cu composites were fabricated by hot-pressing sintering. The composites were characterized with X-ray diffraction, scanning/transmission electron microscopies, and by mea- suring thermal properties, including thermal conductivity and coefficient of thermal expansion （CTE）. The results show that the milled fibers are preferentially oriented in a plane perpendicular to the pressing direction, leading to anisotropic thermal properties of the composites. The Ti coating reacted with graphite fiber and formed a continuous and uniform TiC layer. This carbide layer establishes a good metallurgical interracial bonding in the composites, which can improve the thermal properties effectively. When the fiber content ranges from 35 vol% to 50 vol%, the in-plane thermal conductivities of the composites increase from 383 to 407 W.（m.K）-~, and the in-plane CTEs decrease from 9.5 x 10-6 to 6.3 10-6 K-1.

关键词： Metal matrix composites Titanium coating Microstructure Thermal conductivity Coefficient of thermal expansion

A midgut-specific lytic polysaccharide monooxygenase of Locusta migratoria is indispensable for the deconstruction of the peritrophic matrix

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Insect Science 2022年第5期29卷 1287-1298页

作者： Ming-bo qu xiao-Xi Guo Lin Kong Ling-Jie Hou Qing Yang School of Bioengineering Dalian University of TechnologyDalianLiaoning ProvinceChina State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenGuangdong ProvinceChina

Lytic polysaccharide monooxygenases(LPMOs)are important enzymes that boost the hydrolysis of recalcitrant polysaccharides,such as *** are found extensively in different insect species and are classified as auxiliary activities family 15(AA15)LPMOs(LPMO15).Some of them were identified from the insect midgut and proven to act on ***,knowledge about their physiological roles during insect growth and development remains ***,we found that midgut-specific LPMO15s are widely distributed in different insect orders,such as the orthopteran Locusta migratoria and the lepidopteran bombyx *** *** as a model insect,the function of midgut-specific LmLPMO15-3 during development was ***-stranded RNA-mediated downregulation of LmLPMO15-3 expression at the 4th or 5th instar nymph stage severely decreased the survival rate and resulted in lethal *** and eosin staining results indicated that the deficient individuals exhibited incompletely digested peritrophic matrix(PM),which suggested that LmLPMO15-3 is essential for the deconstruction of the PM during *** study provides direct evidence of the physiological importance of a midgut-specific LPMO15 during insect *** *** is one of the most destructive agricultural pests,LmLPMO15-3 is a potential target for pest management.

关键词： chitin Locusta migratoria lytic polysaccharide monooxygenase midgut peritrophic matrix RNAi

A Review on the Mullins Effect in Tough Elastomers and Gels

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Acta Mechanica Solida Sinica 2024年第2期37卷 181-214页

作者： Lin Zhan Shaoxing qu Rui xiao MOE Key Lab of Disaster Forecast and Control in Engineering College of Mechanics and Construction EngineeringJinan UniversityGuangzhou510632China State Key Laboratory of Fluid Power and Mechatronic System Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceDepartment of Engineering MechanicsZhejiang UniversityHangzhou310027China

Tough elastomers and gels have garnered broad research interest due to their wide-ranging potential ***,during the loading and unloading cycles,a clear stress softening behavior can be observed in many material systems,which is also named as the Mullins *** this work,we aim to provide a complete review of the Mullins effect in soft yet tough materials,specifically focusing on nanocomposite gels,double-network hydrogels,and multi-network *** first revisit the experimental observations for these soft *** then discuss the recent developments of constitutive models,emphasizing novel developments in the damage mechanisms or network *** phenomenological models will also be briefly *** attention is then placed on the anisotropic and multiaxial modeling *** is demonstrated that most of the existing models fail to accurately predict the multiaxial data,posing a significant challenge for developing future anisotropic models tailored for tough gels and elastomers.

关键词： Mullins effect Double-network hydrogels Nanocomposite gels Multi-network elastomers Anisotropic damage model Multiaxial model

Recent Trends in Satellite-Derived Chlorophyll and Aerosol Optical Depth Together with Simulated Dimethylsulfide in the Eastern China Marginal Seas

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Journal of Ocean University of China 2022年第2期21卷 486-498页

作者： qu bo GABRIC Albert J. School of Science Nantong UniversityNantong 266000China School of Environment and Science Griffith UniversityBrisbaneQLDAustralia

The biogenic compound dimethylsulfide(DMS)produced by a range of marine biota is the major natural source of re-duced sulfur to the atmosphere and plays a major role in the formation and evolution of aerosols,potentially affecting *** spatio-temporal distribution of satellite-derived chlorophyll_a(CHL)and aerosol optical depth(AOD)for the recent years(2011-2019)in the Eastern China Marginal Seas(ECMS)(25°-40°N,120°-130°E)are *** seasonal CHL peaks occurred during late April and the CHL distribution displays a clear zonal *** CHL was also observed along the northern and western coastlines during summer and winter *** analysis shows that mean CHL decreases by about 10%over the 9-year study period,while AOD was higher in south and lower in north during summertime.A genetic algorithm technique is used to calibrate the key model parameters and simulations are carried out for 2015,a year when field data was *** simulation results show that DMS seawater concentration ranges from 1.56 to 5.88 nmol L^(−1) with a mean value of 2.76 nmol L^(−1).DMS sea-air flux ranges from 2.66 to 5.00mmol m^(−2) d^(−1) with mean of 3.80mmol m^(−2) d^(−1).Positive correlations of about 0.5 between CHL and AOD were found in the study region,with higher correlations along the coasts of Jiangsu and Zhejiang *** elevated CHL concentration along the west coast is correlated with increased sea-water concentrations of DMS in the *** results suggest a possible influ-ence of DMS-derived aerosol in the local ECMS atmosphere,especially along the western coastline of ECMS.

关键词： dimethylsulfide sea-to-air flux chlorophyll-a aerosol optical depth biogeochemical model Eastern China Marginal Seas

Random Long-Range Interaction Induced Synchronization in Coupled Networks of Inertial Ratchets

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Chinese Physics Letters 2011年第11期28卷 28-30页

作者： WEI Du-qu LUO xiao-Shu CHEN Hong-Bin ZHANG bo College of Electronic Engineering Guangxi Normal UniversityGuilin 541004 College of Engineering and Information Science Huaqiao UniversityXiamen 361021 College of Electric Power South China University of TechnologyGuangzhou 510640

We investigate how the random long-range interactions affect the synchronization features in networks of inertial ratchets,where each ratchet is driven by a periodic time-dependent external force,under the influence of an asymmetric periodic *** is found that for a given coupling strength𝐶,the synchronization of the coupled ratchets is induced as the fraction of random long-range interactions𝑝increases and the ratchet networks reach full synchronization for a larger𝑝.It is also found that the system reaches synchronization more effectively for a stronger coupling strength.

关键词： potential strength coupling