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Integral precession calibration method of PIGA on linear vibration table

Chinese Journal of Aeronautics 2024年第3期37卷 219-236页

作者： Chuang SUN Shun-qing REN Jun-wei CAO ru HUO Department of Automation Tsinghua UniversityBeijing 100084China School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China Faculty of Information technology Beijing University of TechnologyBeijing 100124China

Linear vibration table can provide harmonic accelerations to excite the nonlinear error terms of Pendulous Integrating Gyro Accelerometer(PIGA).Integral precession calibration method is proposed to calibrate PIGA on a linear vibration table in this *** on the precise expressions of PIGA’s inputs,the error calibration model of PIGA is *** angular velocity errors of PIGA are suppressed by integer periodic precession and the errors caused by non-integer periods vibrating are *** complete calibration process,including planning,preparation,PIGA testing,and coefficient identification,is designed to optimize the test operations and evaluate the calibration *** effect of the main errors on calibration uncertainty is analyzed and the relative sensitivity function is proposed to further optimize the test *** and simulation results verify that the proposed 10-position calibration method can improve calibration uncertainties after compensating for the related *** order of calibration uncertainties of the second-and third-order coefficients are decreased to 10^(-8)(rad.s^(-1))/g^(2)and 10^(-8)(rad.s^(-1))/g3,*** with the other two classical calibration methods,the calibration uncertainties of PIGA’s nonlinear error coefficients can be effectively reduced and the proportional residual errors are decreased less than 3×10-6(rad.s^(-1))/g by using the proposed calibration method.

关键词： PIGA Linear vibration table Vibration measurement Calibration Error analysis Uncertainty analysis

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Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： Xin-ru Wang Bao-Zhi Pan Yu-Hang Guo qing-Hui Wang Yao Guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir ***,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably *** the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous *** overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous ***,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric *** we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and ***,it is always difficult to determine the elemental eigenvalues of different minerals in *** paper uses multiple linear regression methods to solve this ***,an integrated inversion technique for altered igneous formations was *** results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray *** results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formation

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model

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The effects of various factors on spontaneous imbibition in tight oil reservoirs

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Petroleum Science 2024年第1期21卷 315-326页

作者： Cheng Liu Tian-ru Wang qing You Yue-Chun Du Guang Zhao Cai-Li Dai School of Energy Resources China University of GeosciencesBeijing100083PR China School of Petroleum Engineering China University of PetroleumQingdao266580ShandongPR China

Slickwater fracturing fluids have gained widespread application in the development of tight oil reservoirs. After the fracturing process, the active components present in slickwater can directly induce spontaneous imbibition within the reservoir. Several variables influence the eventual recovery rate within this procedure, including slickwater composition, formation temperature, degree of reservoir fracture development, and the reservoir characteristics. Nonetheless, the underlying mechanisms governing these influences remain relatively understudied. In this investigation, using the Chang-7 block of the Changqing Oilfield as the study site, we employ EM-30 slickwater fracturing fluid to explore the effects of the drag-reducing agent concentration, imbibition temperature, core permeability, and core fracture development on spontaneous imbibition. An elevated drag-reducing agent concentration is observed to diminish the degree of medium and small pore utilization. Furthermore, higher temperatures and an augmented permeability enhance the fluid flow properties, thereby contributing to an increased utilization rate across all pore sizes. Reduced fracture development results in a lower fluid utilization across diverse pore types. This study deepens our understanding of the pivotal factors affecting spontaneous imbibition in tight reservoirs following fracturing. The findings act as theoretical, technical, and scientific foundations for optimizing fracturing strategies in tight oil reservoir transformations.

关键词： Tight oil reservoir Spontaneous imbibition Nuclear magnetic resonance Slickwater fracturing fluid Fluid utilization degree

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Comparative analysis shows high level of lineage sorting in genomic regions with low recombination in the extended Picea likiangensis species complex

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Plant Diversity 2024年第4期46卷 547-550页

作者： Hui Zhu Weixiao Lei qing Lai Yongshuai Sun Dafu ru State Key Laboratory of Grassland Agro-ecosystems College of EcologyLanzhou UniversityLanzhou 730000China CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China Xi'an Center for Disease Control and Prevention Xi'an 710068China

Genome-scale data,while promising for illuminating phylogenetic relationships,frequently pose a conundrum by yielding conflicting topologies and highly variable gene tree distributions(Pease et al.,2016).This complexity likely arises from the reticulate evolution observed in many taxa,where genetic information exchange occurs through diverse biological processes.

关键词： sorting processes yielding

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A compact X-band backward traveling-wave accelerating structure

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Nuclear Science and Techniques 2024年第5期35卷 13-29页

作者： Xian-Cai Lin Hao Zha Jia-ru Shi Qiang Gao Fang-Jun Hu qing-Zhu Li Huai-Bi Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

Very high-energy electrons(VHEEs)are potential candidates for FLASH radiotherapy for deep-seated *** proposed a compact VHEE facility based on an X-band high-gradient high-power *** this study,we investigated and realized the first X-band backward traveling-wave(BTW)accelerating structure as the buncher for a VHEE facility.A method for calculating the parameters of single cell from the field distribution was introduced to simplify the design of the BTW ***-domain circuit equations were applied to calculate the transient beam parameters of the buncher in the unsteady state.A prototype of the BTW structure with a thermionic cathode-diode electron gun was designed,fabricated,and tested at high power at the Tsinghua X-band high-power test *** structure successfully operated with 5-MW microwave pulses from the pulse compressor and outputted electron bunches with an energy of 8 MeV and a pulsed current of 108 mA.

关键词： Backward traveling-wave accelerating structure Equivalent circuit model High-power test Very high-energy electron radiotherapy

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Overview of the immunological mechanisms in hepatitis B virus reactivation:Implications for disease progression and management strategies

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World Journal of Gastroenterology 2024年第10期30卷 1295-1312页

作者： Hui Ma qing-Zhu Yan Jing-ru Ma Dong-Fu Li Jun-Ling Yang Department of Clinical Laboratory The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Ultrasound Medicine The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Digestive Diseases Center Department of Hepatopancreatobiliary MedicineThe Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Respiratory and Critical Care Medicine The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina

Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease *** review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and *** delves into host immune responses and reactivation’s delicate balance,spanning innate and adaptive *** factors’disruption of this balance,as are interac-tions between viral antigens,immune cells,cytokine networks,and immune checkpoint pathways,are ***,the roles of T cells,natural killer cells,and antigen-presenting cells are discussed,highlighting their influence on disease *** reactivation’s impact on disease severity,hepatic flares,liver fibrosis progression,and hepatocellular carcinoma is *** strategies,including anti-viral and immunomodulatory approaches,are critically *** role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent *** conclusion,this compre-hensive review furnishes a holistic view of the immunological mechanisms that propel HBV *** a dedicated focus on understanding its implic-ations for disease progression and the prospects of efficient management stra-tegies,this article contributes significantly to the knowledge *** more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches,ultimately enhancing disease management and elevating patient *** dynamic landscape of management strategies is critically scrutinized,spanning anti-viral and immunomodulatory *** role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation.

关键词： Hepatitis B virus reactivation Immunological mechanisms Disease progression Management strategies Immune response

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High-efficiency sodium storage of Co_(0.85)Se/WSe_(2) encapsulated in N-doped carbon polyhedron via vacancy and heterojunction engineering

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Carbon Energy 2024年第1期6卷 94-107页

作者： Ya ru Pei Hong Yu Zhou ming Zhao Jian Chen Li Xin Ge Wei Zhang Chun Cheng Yang qing Jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchunChina Jilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy Materials Electron Microscopy CenterJilin UniversityChangchunChina

With the advantage of fast charge transfer,heterojunction engineering is identified as a viable method to reinforce the anodes'sodium storage ***,vacancies can effectively strengthen the Na+adsorption ability and provide extra active sites for Na+***,their synchronous engineering is rarely ***,a hybrid of Co_(0.85)Se/WSe_(2) heterostructure with Se vacancies and N-doped carbon polyhedron(CoWSe/NCP)has been fabricated for the first time via a hydrothermal and subsequent selenization *** aberration-corrected transmission electron microscopy confirms the phase interface of the Co_(0.85)Se/WSe_(2) heterostructure and the existence of Se *** functional theory simulations reveal the accelerated charge transfer and enhanced Na+adsorption ability,which are contributed by the Co_(0.85)Se/WSe_(2) heterostructure and Se vacancies,*** expected,the CoWSe/NCP anode in sodium-ion battery achieves outstanding rate capability(339.6 mAh g^(−1) at 20 A g^(−1)),outperforming almost all Co/W-based selenides.

关键词： Co_(0.85)Se/WSe_(2)heterostructure density functional theory simulations N-doped carbon polyhedron Se vacancies sodium-ion batteries

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Induced Absolute Configuration of Achiral Tetradentate Ligands in Metal–Organic Frameworks for Circularly Polarized Luminescence

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Chinese Journal of Chemistry 2024年第11期42卷 1260-1266页

作者： Hong-ru Fu Dan-Dan Ren Kun Zhang Hong Chen Xiaoyan Lu qing-Rong Ding Lu-Fang Ma College of Chemistry and Chemical Engineering Luoyang Normal UniversityLuoyangHenan471934 China College of Materials&Chemical Engineering China Three Gorges UniversityYichangHubei443002 China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian350002 China

The crystallization of chiral molecules is of great significance to understand the origin and evolution of hierarchical chirality and reveal the relationships between structural chirality and circularly polarized luminescence(CPL)***,we report two pairs of chiral metal–organic frameworks(MOFs)(DCF-17/LCF-17,DCF-18/LCF-18)by utilizing tetradentate ligands tetra(3-imidazoylphenyl)ethylene(TIPE)and 4,4'-[4',5'-bis[4-(4-pyridinyl)phenyl][1,1':2',1”-terphenyl]-4,4”-diyl]bis[pyridine](TPPP)as *** can be observed that the spontaneous resolution of the achiral ligands is converted into the induced resolution,and the ligands form the absolute configuration by using enantiopure camphoric acid(cam)as chiral induced reagent(CIR).As a result,the racemate MOFs can be driven to generate absolute homochiral *** two achiral MOFs[Cd(D-cam)(TPPP)_(0.5)](AF-1,AF=achiral framework)and[Cd(L-cam)(TPPP)_(0.5)](AF-2)were *** position disorder of D/L-cam skeleton causes the generation of nonchiralization,further leading to disappearance of symmetry breaking of *** the perspective of structure,this is the first report which reveals the chiral transfer and nonchiralization between chiral induced agents and tetradentate ***,DCF-17 and LCF-17 show CPL with luminescence dissymmetry factor(glum)of–1.0×10^(-2)and+9.2×10^(–3),*** work provides the useful evidences to reveal the induced chiral crystallization and the construction of CPL-active crystalline materials.

关键词： Metal-organic frameworks Circularly polarized luminescence Chirality induction Spontaneous resolution Chirality transfer

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Recovering from prolonged cardiac arrest induced by electric shock:A case report

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World Journal of Clinical Cases 2024年第13期12卷 2248-2253页

作者： Jian Zhang Yan-ru Qiao Ya-Dong Yang Guo-Zheng Pan Chong-qing Lv Department of General Surgery Shengli Oilfield Central HospitalDongying 257000Shandong ProvinceChina Department of Emergency Medicine Shengli Oilfield Central HospitalDongying 257000Shandong ProvinceChina

BACKGROUND Cardiac arrest(CA)induced by electric shock is a rare occurrence,particularly in cases of prolonged ***,there is limited literature on similar incidents,and we present a relevant case *** SUMMARY A 27-year-old Asian male man,experiencing respiratory CA due to electric shock,was successfully restored to sinus rhythm after 50 min of cardiopulmonary resuscitation and 8 electrical defibrillation *** the subsequent stages,the patient received multiple organ function protection measures,leading to a successful recovery and eventual discharge from the *** Prolonging resuscitation time can enhance the chances of survival for patients,this study provide valuable insights into the management of electric shock-induced CA.

关键词： Electric shock Cardiac arrest Prolonged cardiopulmonary resuscitation Cerebral resuscitation Case report

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Climate warming is likely to weaken the performance of two-phase closed thermosyphon on the qinghai-Tibet Plateau

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Advances in Climate Change Research 2024年第1期15卷 90-100页

作者： Guan-Li JIANG Zi-Teng FU Xin-Yu MEN Hong-Ting ZHAO Si-ru GAO Yong-Zhi LI qing-Bai WU State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Beiluhe Observation and Research Station on Frozen Soil Engineering and Environment in the qinghai-Tibet Plateau Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Muli Field Scientific Observation and Research Station for Gas Hydrate China Geological SurveyBeijing 100083China University of Chinese Academy of Sciences Beijing 100049China School of Civil Engineering and Architecture Jiaxing Nanhu UniversityJiaxing 314001China

Over the years,numerous geotechnical approaches have been implemented to mitigate the adverse effects of climate warming on various infrastructures in the permafrost region of the qinghai-Tibet Plateau(QTP),such as the qinghai-Tibet Highway and Railway,and achieved the expected engineering ***,little attention has been given to whether the performance of these geotechnical approaches has changed during the ongoing process of climate *** investigate the performance variation of one of these geotechnical approaches,which is two-phase closed thermosyphon(TPCT),during sustained climate warming,we conducted a statistical analysis of soil temperature monitoring data in 2003-2020 from eight regular embankments and six TPCT embankments in our permafrost monitoring *** results indicate that TPCT undeniably has a cooling effect on the permafrost beneath embankments,even rapidly eliminated previously formed taliks beneath ***,further analysis reveals that the performance of TPCT has been weakening during sustained climate warming,which has confirmed by the re-forming of the taliks beneath embankment where they had been previously *** on the current understanding,we attributed the weakening of thermosyphon performance to a significant reduction in the air temperature freezing index caused by ongoing climate *** this study,we aimed to draw attention to the evolving performance of geotechnical approaches in permafrost regions amid climate warming,prompting necessary engineering innovations to address this situation and ensure the sustainable development of the permafrost region on the QTP.

关键词： Two-phase closed thermosyphon Climate warming Supra-permafrost talik Permafrost degradation qinghai-Tibet Highway

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