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Melting geodynamics reveals a subduction origin for the Purang ophiolite,Tibet,China

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Acta Geochimica 2024年第4期43卷 754-773页

作者： Tao Ruan Zhong-Jie Bai wei-guang Zhu shi-Ji Zheng State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The debate regarding whether the Yarlung-Zangbo ophiolite(YZO)on the south of the Qinghai-Tibet Plateau,formed in a mid-ocean ridge(MOR)or a supra-subduction zone(SSZ)setting has remained *** we present petrological,mineralogical,and geochemical data associated with modeling melting geodynamics of the mantle peridotites from the Purang ophiolite in the western segment of the Yarlung-Zangbo Suture Zone(YZSZ)to explore its tectonic *** Purang lherzolites are characterized by the protogranular texture and have abyssal-peridotite-like mineral compositions,including low Cr^(#)(20-30)and TiO_(2) contents(<0.1wt%)in spinel,high Al_(2)O_(3)(2.9wt%-4.4wt%)and CaO(1.9wt%-3.7wt%)contents in orthopyroxene and LREE-depletion in *** of these lherzolites can be modeled by~11%dynamic melting of the DMM source with a small fraction of melt(~0.5%)entrapped within the source,a similar melting process to typical abyssal *** Purang harzburgites are characterized by the porphyroclastic texture and exhibit highly refractory mineral compositions such as high spinel Cr^(#)(40-68),low orthopyroxene Al_(2)O_(3)(<2.2wt%)and CaO(<1.1wt%)*** in these harzburgites are enriched in Sr(up to 6.0 ppm)and LREE[(Ce)N=0.02-0.4],but depleted in Ti(200 ppm,on average)and HREE[(Yb)N<2].Importantly,the more depleted samples tend to have higher clinopyroxene Sr and LREE *** observations indicate an open-system hydrous melting with a continuous influx of slab fluid at a subduction *** modeled results show that these harzburgites could be formed by 19%-23%hydrous melting with the supply rate of slab fluid at 0.1%-1%.The lower clinopyroxene V/Sc ratios in harzburgites than those in lherzolites suggest a high oxidation stage of the melting system of harzburgites,which is consistent with a hydrous melting environment for these *** is therefore concluded that the Purang ophiolite has experienced a transformat

关键词： Melting geodynamics SSZ peridotites MOR peridotites Clinopyroxene Purang ophiolite

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Circumspinal decompression through a single posterior incision to treat thoracolumbar disc herniation

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Chinese Medical Journal 2011年第23期124卷 3852-3857页

作者： QI Qiang CHEN Zhong-qiang LIU Ning GUO Zhao-qing shi Ze-feng LIU Zhong-jun LIU Xiao-guang LI wei-shi ZENG Yan SUN Chui-guo Department of Orthopaedics Peking University Third Hospital Beijing 100191 China

Various surgical approaches have been successfully used in the treatment of thoracolumbar disc herniation （TLDH）. Although the anterior transthoracic approach has a reputation for better visualization than the posterolateral and lateral approaches, it involves the manipulation of the thoracic and pulmonary structures. Thus, this approach is technically demanding and prone to compromising the respiratory system. An ideal approach would involve adequate visualization and be accomplished through the posterior midline approach that is familiar to spine surgeons. The objective of this retrospective preliminary clinical study was to introduce a new surgical procedure, circumspinal decompression through a single posterior incision, for the treatment of TLDH （T10/11-L1/2） and to evaluate the surgical outcome of this procedure by comparing it to the conventional anterior transthoracic approach. Methods In this study, 15 patients （10 males, 5 females; mean age 51 years） with symptomatic TLDH underwent the circumspinal decompression through a single posterior incision procedure between January 2008 and December 2009. Altogether, 17 herniated discs were excised, with 2 discs at T10/11, 4 discs at Tll/12, 5 discs at T12/L1 and 6 discs at L1/2. Of these patients, 13 were followed up with a mean follow-up period of 23.5 months. Clinical outcomes, including operative time, blood loss, perioperative complications, postoperative time of hospitalization, neurologic status improvement, back pain and correction of local kyphosis, were investigated by comparing these data with the results from patients who underwent the anterior transthoracic approach for TLDH during the same period. The patients＇ neurologic status was evaluated by a modified Japanese Orthopedic Association （JOA） scoring system of 11 points. Neurologic status improvement after the surgery was assessed by calculating the recovery rate, which was equal to the （postoperative JOA score-preoperative JOA score）/（11-preoperativ

关键词： thoracolumbar disc herniation circumspinal decompression thoracic spine

A Comprehensive Study of the Association between LEPR Gene rs1137101 Variant and Risk of Digestive System Cancers

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Biomedical and Environmental Sciences 2024年第5期37卷 445-456页

作者： HU wei Qiong ZHOU wei guang ZHOU guang wei LIAO Jia Xi shi Jia Xing XIE FengYang LI Shou Heng WANG Yong FENG Xian Hong GU Xiu Li CHEN Bi Feng Department of Biological Science and Technology School of ChemistryChemical Engineering and Life SciencesWuhan University of TechnologyWuhan 430070HubeiChina Institute of WUT-AMU Wuhan University of TechnologyWuhan 430070HubeiChina Department of Clinical Laboratory Wuhan Xinzhou District People’s HospitalWuhan 430499HubeiChina Department of Reproductive Genetics Wuhan Huake Reproductive HospitalWuhan 430013HubeiChina

Objective The leptin receptor,encoded by the LEPR gene,is involved in tumorigenesis.A potential functional variant of LEPR,rs1137101(Gln223Arg),has been extensively investigated for its contribution to the risk of digestive system(DS)cancers,but results remain conflicting rather than ***,we performed a case–control study and subsequent meta-analysis to examine the association between rs1137101 and DS cancer *** A total of 1,727 patients with cancer(gastric/liver/colorectal:460/480/787)and 800 healthy controls were *** of rs1137101 was conducted using a polymerase chain reactionrestriction fragment length polymorphism(PCR-RFLP)assay and confirmed using Sanger ***-four eligible studies were included in the *** After Bonferroni correction,the case–control study revealed that rs1137101 was significantly associated with the risk of liver cancer in the Hubei Chinese *** meta-analysis suggested that rs1137101 is significantly associated with the risk of overall DS,gastric,and liver cancer in the Chinese *** The LEPR rs1137101 variant may be a genetic biomarker for susceptibility to DS cancers(especially liver and gastric cancer)in the Chinese population.

关键词： LEPR gene rs1137101 Digestive system cancers Genetic susceptibility Meta-analysis

Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020

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Plant Diversity 2024年第1期46卷 70-77页

作者： shi-guang wei Lin Li Kun-Dong Bai Zhi-Feng Wen Jing-Gang Zhou Qin Lin Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(guangxi Normal University) Ministry of EducationGuilin 541004GuangxiChina School of Life&Environmental Sciences Guilin University of Electronic TechnologyGuilin 541004GuangxiChina guangxi Key Laboratory of Landscape Resources Conservation and Sustainable Utilization in Lijiang River Basin Guilin 541004GuangxiChina Key Laboratory of Vegetation Restoration and Management of South China Botanical Garden of Degraded Ecosystems Chinese Academy of SciencesGuangzhou 510650GuangdongChina Center of Plant Ecology Core Botanical GardensChinese Academy of SciencesGuangzhou 510650GuangdongChina

Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in *** found that community structure in this forest changed over a 15-year ***,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya *** numbers of individual deaths for common species were concentrated in the small and mid-diameter *** spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats *** 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey *** weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved *** findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure.

关键词： Community structure Death and renewal dynamics Species diversity dynamics South subtropical forest

Design and application of copper/lithium composite anodes for advanced lithium metal batteries

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Rare Metals 2024年第3期43卷 942-970页

作者： Bin Zhang Ji-Ping Ma Yang Zhao Tong Li Jin-Lin Yang Zhan-Ling Zhang shi-Zhong wei guang-Min Zhou School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471003China Shenzhen Geim Graphene Center Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore Shenzhen Geim Graphene Center Tsinghua-Berkeley Shenzhen InstituteTsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China

Lithium(Li)is a promising candidate for nextgeneration battery anode due to its high theoretical specific capacity and low reduction ***,safety issues derived from the uncontrolled growth of Li dendrite and huge volume change of Li hinder its practical application.C onstructing dendrite-free composite Li anodes can significantly alleviate the above ***(Cu)-based materials have bee n widely used as substrates of the composite electrodes due to their chemical stability,excellent conductivity,and good mechanical ***/lithium(Cu/Li)composite anodes significantly regulate the local current density and decrease Li nucleation overp otential,realizing the uniform and dendrite-free Li *** this review,Cu/Li composite methods including electrodeposition,melting infusion,and mechanical rolling are systematically summarized and ***,design strategies of Cu-based current collectors for high performance Cu/Li composite anodes are *** challenges and future development for Cu/Li composite anodes are presented and *** hope that this review can provide a comprehensive understanding of Cu/Li composite methods of the latest development of Li metal anode and stimulate more research in the future.

关键词： Lithium metal batteries Cu/Li composite anode Electrodeposition Thermal melting infusion Mechanical rolling

The tangential k-Cauchy-Fueter type operator and Penrose type integral formula on the generalized complex Heisenberg group

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 181-190页

作者： REN guang-zhen shi Yun KANG Qian-qian Department of Mathematics Zhejiang International Studies UniversityHangzhou 310023China Department of Mathematics Zhejiang University of Science and TechnologyHangzhou 310023China

The tangential k-Cauchy-Fueter operator and k-CF functions are counterparts of the tangential Cauchy–Riemann operator and CR functions on the Heisenberg group in the theory of several complex variables,*** this paper,we introduce a Lie group that the Heisenberg group can be imbedded into and call it generalized complex *** investigate quaternionic analysis on the generalized complex *** also give the Penrose integral formula for k-CF functions and construct the tangential k-Cauchy-Fueter complex.

关键词： the generalized complex Heisenberg group the tangential k-Cauchy-Fueter type operator Penrose-type integral formula

Motion-pressure coupled control and simulation of long-endurance capability for multicapsule stratospheric airships

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Chinese Journal of Aeronautics 2024年第6期37卷 137-150页

作者： Zhiguang shi wei HUO Zongyu ZUO School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Beijing Near Space Airship Technology Development Co. LtdBeijing 100070China

The current study focuses on the motion-pressure coupled control for a multicapsule stratospheric airship and transforms the path-tracking and heading-hold control of airships into guidance tracking with a time-varying weighted sum of longitudinal and lateral velocities by the definition of compound ***,an improved nonlinear predictive control method is provided to reduce the control energy consumption by the rolling optimization of controller parameters based on finite time intervals,ensuring infinite-time path-tracking ***,combined with the proposed cyclic regulation process of safe pressure between internal and external capsules,this study can fully reflect the force-thermal coupled rule of airships under the actions of atmospheric environment and maneuvering force,while evaluating the long-endurance capability of airships under the conditions of safe superheating and *** effectiveness of the motionpressure coupled controller was verified through numerical simulations,which can overcome the influence of environmental wind and achieve a tracking effect for the desired cruise path and compound *** airspeed provided during the cyclic circadian time caused the maximum superheating of the helium controlled within 30*** helium in the internal and external capsules achieved circadian *** equivalent micropore diameter of the capsule of 5 mm can achieve 55 days of long-endurance *** controller satisfies the requirements of cruise-flight application modes for multicapsule stratospheric airships with important engineering value.

关键词： Compound speed Nonlinear predictive control Cyclic pressure regulation Long-endurance capability Stratospheric airship

Atomic-scale mechanism of effect of co-separation of elements at interface of ferrite and austenite on Cr-depleted zone of duplex stainless steel

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Journal of Iron and Steel Research International 2024年第3期31卷 710-718页

作者： Yan-hui Hou Ze-kun Xu shi-long Zhou guang-qiang Li The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Three-dimensional atom-probe tomography and first-principles calculation combined with density functional theory were used to study the effect of the co-segregation of different elements formed during the solidification process of S32205 duplex stainless steel on the Cr-depleted zone at the interface between ferrite and *** was found that the co-segregation of different elements formed during the solidification process of duplex stainless steel can also form Cr-depleted zone at the interface between ferrite and ***,Mo,Si,B,C and P atoms promote co-segregation with Cr atoms,which promotes the formation of Cr-depleted zone at the interface between ferrite and austenite in duplex stainless *** and Si strongly promote the segregation of Cr at the interface between ferrite and austenite,thereby promoting the formation of Cr-depleted zone.B,C and P elements also promote the segregation of Cr element at the interface between ferrite and austenite and the formation of Cr-depleted zone,but their effect is weaker than that of Mo and Si *** conclusions provide a new theoretical basis for improving the intergranular corrosion performance of duplex stainless steel.

关键词： Duplex stainless steel Cr-depleted zone Intergranular corrosion Co-segregation First-principles calculation

A discussion of fatigue properties of notched specimens subjected to prestressing treatment machined from FGH4097

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Chinese Journal of Aeronautics 2024年第4期37卷 508-523页

作者： Rongxi shi Dasheng wei Le HAN Shun YANG School of Energy and Power Engineering Beihang UniversityBeijing 100191China Jiangxi Research Institute Beihang UniversityNanchang 330096China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

Experimental and numerical investigations were performed to reveal the effect of prestress on the fatigue properties of FGH4097 so as to quantitatively evaluate the overspeed benefit of the disc of aeroengine. A corresponding experiment was performed to examine the effect of prestress on the fatigue life of FGH97. A complete model describing the fatigue properties of the prestressed notch specimen was proposed. After the modification of mean stress, stress gradient and prestressing treatment, the model is finally verified by fatigue test of presstressed notch specimens machined from FGH4097 with satisfactory accuracy and good engineering applicability. The new model highlights that for the variable fatigue loads, the introduction of appropriate prestress is expected to benefit to the notch specimens and certainly to the disc of aeroengine regards of their fatigue properties. Both the calculation method of fatigue life parameters and the prestress correction model are proved to have good prediction accuracy.

关键词： Turbine blisk Overspeed test Prestress Fatigue life prediction FGH4097