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Mechanical Modeling and Analysis of Stability Deterioration of Production Well During Marine Hydrate Depressurization Production

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China Ocean Engineering 2024年第2期38卷 338-351页

作者： SUN Huan-zhao CHANG yuan-jiang SUN Bao-jiang WANG Kang CHEN Guo-ming LI Hao DAI Yong-guo Centre for Offshore Engineering and Safety Technology China University of Petroleum(East China)Qingdao 266580China School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China jiangsu Shuguang Oil Tools Co. LtdTaizhou 225532China

Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate ***,the formations will undergo significant subsidence during depressurization,which will destroy the original force state of the production ***,existing research on the stability of oil and gas production wells assumes the formation to be stable,and lacks consideration of the force exerted on the hydrate production well by formation subsidence caused by hydrate decomposition during *** fill this gap,this paper proposes an analytical method for the dynamic evolution of the stability of hydrate production well considering the effects of hydrate *** on the mechanical model of the production well,the basis for stability analysis has been proposed.A multi-field coupling model of the force state of the production well considering the effect of hydrate decomposition and formation subsidence is established,and a solver is *** analytical approach is verified by its good agreement with the results from the numerical method.A case study found that the decomposition of hydrate will increase the pulling-down force and reduce the supporting force,which is the main reason for the stability *** higher the initial hydrate saturation,the larger the reservoir thickness,and the lower the production pressure,the worse the stability or even *** work can provide a theoretical reference for the stability maintaining of the production well.

关键词： natural gas hydrate production well depressurization production formation deformation stability deterioration

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Effect of Al content on modification behavior of non-metallic inclusions in high-strength steel treated with rare earth

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Journal of Iron and Steel Research International 2024年第8期31卷 1886-1899页

作者： Zhan-peng Tie Xue-yuan jiang Hai-yan Tang ·Gen Li Yu-hang Wang Jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Continuous Casting Business Section CISDI Engineering Co.Ltd.Chongqing 401122China Special Steel Institute Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

The influence of Al content(0.0053,0.0171,and 0.0578 wt.%)on the modification behavior of non-metallic inclusions in 20CrMoVTiB steel treated with rare earth elements was studied through high-temperature experiments and thermodynamic *** results showed that the modification products varied with the Al content in steel under 0.01 wt.%of Ce *** formation sequence of typical rare earth inclusions in steel with the increase in Al content was Ce_(2)O_(3)→CeAlO_(3)→CeAl_(11)O_(18),and the final stable products were highly Al content *** the Al content was 0.0053 wt.%,the stable phase in steel was Ce2O3;while the[Al]reached 0.0171 wt.%,the stable phase became CeA1O_(3).As the A1 content reached 0.0578 wt.%,CeAl_(11)O_(18) became the stable *** a result,increasing the Al content could inhibit the precipitation of Ce_(2)O_(3) inclusions in steel while promote the formation of CeAIO3 and CeAl_(11)O_(18) *** addition,both Ca treatment and Ce treatment could effectively refine the size of inclusions in steel by changing their ***,the feeding amount of Ca wire into molten steel should be appropriately reduced under the condition of adding Ce simultaneously,which is expected to be beneficial for an improved Ce treatment effect.

关键词： Rare earth Al content Steel Inclusion Thermodynamics Ca treatment

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Dynamic Analysis of A Deepwater Drilling Riser with A New Hang-off System

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China Ocean Engineering 2024年第1期38卷 29-41页

作者： LI Yan-wei LIU Xiu-quan WANG Jin-long CHEN Guo-ming CHANG yuan-jiang SHENG Lei-xiang Centre for Offshore Engineering and Safety Technology China University of PetroleumQingdao 266580China National Engineering Laboratory of Offshore Geophysical and Exploration Equipment China University of PetroleumQingdao 266580China China CNOOC Research Institute Co. Ltd.Beijing 100028China

The safety of risers in hang-off states is a vital challenge in offshore oil and gas engineering.A new hang-off system installed on top of risers is proposed for improving the security of *** approach leads to a challenging problem:coupling the dynamics of risers with a new hang-off system combined with multiple structures and complex *** accurately analyze the dynamic responses of the coupled system,a coupled dynamic model is established based on the Euler-Bernoulli beam-column theory and penalty function method.A comprehensive analysis method is proposed for coupled dynamic analysis by combining the finite element method and the Newmarkβ*** analysis program is also developed in MATLAB for dynamic *** simulation results show that the dynamic performances of the risers at the top part are significantly improved by the new hang-off system,especially the novel design,which includes the centralizer and articulation *** bending moment and lateral deformation of the risers at the top part decrease,while the hang-off joint experiences a great bending moment at the bottom of the lateral restraint area which requires particular attention in design and *** platform navigation speed range under the safety limits of risers expands with the new hang-off system in use.

关键词： deepwater drilling riser new hang-off system dynamic analysis finite element method penalty function method

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Structural Properties of Ions and Polyelectrolytes in Aqueous Solutions under External Electric Fields:The Sign Effect

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Chinese Journal of Polymer Science 2024年第9期42卷 1341-1352,I0007页

作者： Cheng-jiang Lin Jun-Jun Wang yuan jiang Shu-Li Chen Hong-Fei Li Wen-Han Zhao Qing-Rong Huang Chang-Ru Rong Xiao-Zheng Duan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China National Key Laboratory of Advanced Vehicle Integration and Control China FAW Group Co.Ltd.Changchun130013China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200438China Department of Food Science Rutgers University65 Dudley RoadNew BrunswickNew Jersey08901USA

We utilize molecular dynamics simulations to investigate the microstructures of ions and polyelectrolytes in aqueous solutions under external electric *** focusing on the multi-body interactions between ionic components and H_(2)O molecules,as well as their responses to the external electric fields,we clarify several nontrivial molecular features of the ionic and polyelectrolyte solutions,such as the solvations of cations and anions,clustering of the ions,and dispersions/aggregations of polyelectrolyte chains,as well as the corresponding responses of H_(2)O molecules in these *** simulations illustrate the variations in structures of ionic solutions caused by reversing the charge sign of the ions,and elucidate the disparity in structures between anionic and cationic polyelectrolyte solutions in the presence of the external electric *** work clarifies the mechanism for the alternations in complex multi-body interactions in aqueous solutions caused by the application electric field,which can contribute to the fundamental understanding of the physical and chemical natures of ion-containing and charged polymeric systems.

关键词： Polyelectrolyte Ions Aqueous solutions External electric fields Asymmetric dipole

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Delivery room resuscitation intensity and associated neonatal outcomes of 24^(+0)-31^(+6) weeks'preterm infants in China:a retrospective cross-sectional study

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World Journal of Pediatrics 2024年第1期20卷 64-72页

作者： Si-Lu Wang Chun Chen Xin-Yue Gu Zhao-Qing Yin Le Su Si-yuan jiang Yun Cao Li-Zhong Du Jian-Hua Sun jiang-Qin Liu Chuan-Zhong Yang Department of Neonatology Shanghai Key Laboratory of Maternal Fetal MedicineShanghai Institute of Maternal-Fetal Medicine and Gynecologic OncologyShanghai First Maternity and Infant HospitalSchool of MedicineTongji UniversityNo.2699Gaoke Western RoadPudong DistrictShanghai 201204China Department of Neonatology Affiliated Shenzhen Maternity and Child Healthcare HospitalSouthern Medical UniversityNo.2004Hongli RoadFutian DistrictShenzhen 518028China NHC Key Laboratory of Neonatal Diseases Fudan UniversityChildren's Hospital of Fudan UniversityShanghaiChina Department of Neonatology People's Hospital of DehongKunming Medical UniversityDehongChina Department of Neonatology Children's Hospital of Fudan UniversityShanghaiChina Department of Neonatology Children's HospitalZhejiang University School of MedicineHangzhouChina Department of Neonatology Shanghai Children's Medical CenterSchool of MedicineShanghai Jiao Tong UniversityShanghaiChina

Background The aim of this study was to review current delivery room(DR)resuscitation intensity in Chinese tertiary neonatal intensive care units and to investigate the association between DR resuscitation intensity and short-term outcomes in preterm infants born at 24+0_31+6 weeks gestation age(GA).Methods This was a retrospective cross-sectional *** source population was infants born at 24+0_31+6 weeks'GA who were enrolled in the Chinese Neonatal Network 2019 *** infants were categorized into five groups:(1)regular care;(2)oxygen supplementation and/or continuous positive airway pressure(O2/CPAP);(3)mask ventilation;(4)endotracheal intubation;and(5)cardiopulmonary resuscitation(CPR).The association between DR resuscitation and shortterm outcomes was evaluated by inverse propensity score-weighted logistic *** Of 7939 infants included in this cohort,2419(30.5%)received regular care,1994(25.1%)received O,/CPAP,1436(18.1%)received mask ventilation,1769(22.3%)received endotracheal intubation,and 321(4.0%)received CPR in the *** maternal age and maternal hypertension correlated with a higher need for resuscitation,and antenatal steroid use tended to be associated with a lower need for resuscitation(P<0.001).Severe brain impairment increased significantly with increasing amounts of resuscitation in DR after adjusting for perinatal *** strategies vary widely between centers,with over 50%of preterm infants in eight centers requiring higher intensity *** Increased intensity of DR interventions was associated with increased mortality and morbidities in very preterm infants in *** is wide variation in resuscitative approaches across delivery centers,and ongoing quality improvement to standardize resuscitation practices is needed.

关键词： Cardiopulmonary resuscitation Delivery room Endotracheal intubation Neonatal resuscitation Preterm

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Harnessing cytokine-induced killer cells to accelerate diabetic wound healing:an approach to regulating post-traumatic inflammation

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Regenerative Biomaterials 2024年第2期3卷 88-99页

作者： Yixi Yang Cheng Zhang yuan jiang Yijun He iawei Cai Lin Liang Zhaohuan Chen Sicheng Pan Chu Hua Keke Wu Le Wang Zhiyong Zhang Translational Research Centre of Regenerative Medicine and 3D Printing of Guangzhou Medical University Guangdong Province Engineering Research Center for Biomedical EngineeringState Key Laboratory of Respiratory DiseaseDepartment of Orthopaedic SurgeryMedical Technology and Related Equipment Research for Spinal Injury TreatmentCity Key LaboratoryThe Third Affliated Hospital of Guangzhou Medical UniversitySchool of Biomedical EngineeringGuangzhou MedicalUniversityGuangzhouGuangdong510150P.R.China Department of Osteoarthropathy and Sports Medicine Panyu Central HospitalGuangzhou 511400P.R.China

Impaired immunohomeostasis in diabetic wounds prolongs infiammation and cytokine dysfunction,thus,delaying or pre-venting wound-surface *** clinical studies have been conducted on cytokine-induced killer(CIK)cells recently,as they can be easily proliferated using a straightforward,inex-pensive ***,the function of CIK cells in regulat-ing inflammatory environments has been drawing attention for clinical *** the current investigation,we discovered the regenerative capacity of these cells in the chal-lenging environment of wounds that heal poorly due to *** demonstrated that the intravenous injection of CIK cells can re-establish a proregenerative inflammatory *** *** accelerateskin healing in diabetic *** results indicated that CIK cell treatment affects macrophage polarization and restores the function regenerative cells under hyperglycemic *** novel cellular therapy offers a promising intervention for clinical applic tions through specific inflammatory regulation functions.

关键词： macrophage diabetic wound post-traumatic inflammation cytokine-induced killer cells vascularization

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基于改进强耦合振子的微弱脉冲信号检测方法

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物理学报 2024年第4期73卷 88-97页

作者：李远芳姜园赵磊中山大学电子与通信工程学院深圳518107

强耦合振子可用于微弱脉冲信号的检测和波形恢复,但其对微弱脉冲信号的检测频率会受到系统内置频率的限制.在系统内置频率固定的情况下,系统只能对一定频率范围内的脉冲信号进行有效检测和波形恢复,在检测更高频率的脉冲信号时会出现波... 详细信息

强耦合振子可用于微弱脉冲信号的检测和波形恢复,但其对微弱脉冲信号的检测频率会受到系统内置频率的限制.在系统内置频率固定的情况下,系统只能对一定频率范围内的脉冲信号进行有效检测和波形恢复,在检测更高频率的脉冲信号时会出现波形失真.本文分析了耦合振子内置频率和微弱脉冲信号检测频率之间的关系,提出两种改进强耦合振子结构以扩展微弱脉冲信号的频率检测范围.通过引入非线性恢复力耦合项,非线性恢复力强耦合振子可以有效保留信号的高频分量,在更高频率的脉冲信号输入时也能较好地保留信号特征.双振子强耦合系统通过引入Van der Pol-Duffing振子,加强了系统内部结构的稳定性,同样达到了扩展脉冲信号频率检测范围的效果.此外,基于变迭代步长和混沌检测的频率相关性,提出了一个未知频率脉冲信号检测方法,以改变迭代步长的方法代替改变系统内置频率来进行频率扫描,并且利用混沌检测的频率相关性,将接收信号和恢复信号的相关系数和纯噪声输入情况下的相关系数进行对比,根据两个相关系数之间的明显差异可以有效检测出脉冲信号.通过仿真实验进行验证,所提方法可以有效检测出未知频率的脉冲信号,并且所提的改进强耦合振子结构相对于强耦合振子有较大的性能提升.

关键词：强耦合非线性恢复力强耦合振子双振子强耦合系统微弱脉冲瞬态脉冲

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账面—市值比分解视角下的价值溢价成因：风险还是预期差

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金融经济学研究 2024年第5期039卷 98-112页

作者：姜圆青海大学金融发展研究中心青海大学财经学院

尽管多因素定价模型为学术界广泛接受，但其因子有效性源于公司基本面风险差异还是投资者预期差，依然存在分歧。选取账面—市值比B/M测度价值溢价，将其分解为账面—价值比(B/V)和价值—市值比(V/M),研究已有记载的7种风险假说是否能... 详细信息

尽管多因素定价模型为学术界广泛接受，但其因子有效性源于公司基本面风险差异还是投资者预期差，依然存在分歧。选取账面—市值比B/M测度价值溢价，将其分解为账面—价值比(B/V)和价值—市值比(V/M),研究已有记载的7种风险假说是否能够充分呈现价值溢价的因果逻辑。结果发现，B/M对预期收益率的解释力与V/M相当，而B/V的差异则不能解释预期收益率差异。进一步地，财务困境风险假说、个股现金流风险假说，既不能一致地解释B/M之间的差异，亦不能解释V/M之间的差异；股权隐含违约风险假说、系统性风险敏感性假说、市场现金流风险假说、营运杠杆风险假说、股权久期风险假说这五类理论，虽可解释B/V的差异，但无法解释V/M的差异。基于线性外推偏差假说和套利风险理论，讨论了V/M在市场上产生和持续存在的原因。研究支持行为金融学中价值溢价成因的预期差假说，对以Fama and French(1993)为代表的多因素模型在中国A股市场上是否可由风险理论所解释提出质疑，由此基于“价值溢价消失之谜”这一前沿学术问题提供了重要参考。

关键词：价值溢价风险预期差账面—市值比

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获量配额管理中地方政府的失能与赋能——以渔业法律的责任体系与考评机制为视角

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山东大学学报（哲学社会科学版） 2024年第2期 69-79页

作者：姜渊宁波大学法学院宁波315211

在我国渔业管理中,获量配额是一项“早早提出”却“未被贯彻”的管理模式。当前有关获量配额管理的学术研究大多集中在呼吁相关制度的贯彻落实,却不曾关注地方政府实施获量配额管理的动能。事实上,获量配额管理具备典型的行政发包制特性... 详细信息

在我国渔业管理中,获量配额是一项“早早提出”却“未被贯彻”的管理模式。当前有关获量配额管理的学术研究大多集中在呼吁相关制度的贯彻落实,却不曾关注地方政府实施获量配额管理的动能。事实上,获量配额管理具备典型的行政发包制特性,其治理成败的关键之一是以科学的责任体系与考评机制来为地方政府赋能。Z省渔业权改革遇到了诸多阻碍,核心问题是地方政府在治理中的失能。而动能的匮乏又来源于渔业法律中不洽的责任体系与考评机制。解决失能问题的思路是修正责任体系与考评机制,即增设责任规则和重设考评标准,从而确保地方政府可以通过获量配额管理来获得相应政绩,进而为其重新赋能。围绕上述思路,渔业法律应当从全方位进行立法改革。

关键词：渔业管理获量配额地方政府失能赋能

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河林长制的环境质量责任审视

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理论探索 2024年第4期 20-27页

作者：姜渊宁波大学浙江宁波255100

现有针对河林长制的责任研究只关注于其对责任压力的强化与整合。事实上,河林长制实现了责任属性的变革性创新与责任主体的拓展性创新。进而,它以目标性责任将党政领导的政治责任与地方政府的法律责任予以结合,从而围绕环境质量责任进... 详细信息

现有针对河林长制的责任研究只关注于其对责任压力的强化与整合。事实上,河林长制实现了责任属性的变革性创新与责任主体的拓展性创新。进而,它以目标性责任将党政领导的政治责任与地方政府的法律责任予以结合,从而围绕环境质量责任进行了责任机制的建构。具体而言,河林长制从责任机制的三个方面对环境质量责任予以建设性践行:一是赋予地方政府具体的环境治理职能,二是将新赋予的环境治理职能融于宏观治理之中,三是以标准化的环境质量目标达标机制督促地方政府履行环境质量责任。

关键词：环境质量责任河长制林长制责任属性责任主体

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