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Insight into the mechanism of 5-hydroxymethylfurfural electroreduction to 2,5-bis(hydroxymethyl)furan over Cu anchored N-doped carbon nanosheets

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Nano Research 2024年第9期17卷 7991-7999页

作者： Haoran wu Xinwei chen Haishan Xu Runlu Yang Xin Wang Junying chen Zhenbing Xie Liang wu Yiyong Mai School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgeingShanghai Jiao Tong UniversityShanghai 200240China Department of Chemistry Tangshan Normal UniversityTangshan 063000China

Design of non-noble metal electrocatalysts for biomass conversion to high-value chemicals and understanding the related catalytic mechanisms are of profound significance but have remained a major ***,we developed a novel biomass-derived electrocatalyst(denoted as Cu/NC),featuring with electron-deficient copper nanoparticles anchored on N-doped carbon nanosheets,for the electrochemical reduction of 5-hydroxymethylfurfural(HMF)to 2,5-bis(hydroxymethyl)furan(BHMF,a vital precursor of functional polymers).The optimized Cu/NC electrocatalyst exhibited an excellent performance with high Faradaic efficiency(89.5%)and selectivity(90.8%)of BHMF at a low concentration of HMF(18.1 mM).Even at a very high HMF concentration(108.6 mM),the Faraday efficiency and selectivity of BHMF could still reach 74.8%and 81.1%,*** performance approached those of the reported noble metal-based *** study revealed that the N doping in the Cu/NC catalyst could regulate the electronic structure of Cu,strengthening the adsorption of the HMF carbonyl group,and thus boosting the selectivity of ***,strong electronic metal-support interactions of Cu and the N-doped carbon support optimized the charge transfer rate,thus promoting the dissociation of water to the active hydrogen(H^(*))species and boosting the reaction kinetic rate of H^(*)and HMF.

关键词： biomass 5-hydroxymethylfurfural electrochemical reduction N-doped carbon materials 2,5-bis(hydroxymethyl)furan

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Moving doubly heavy baryon in a strongly coupled plasma via holography

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Chinese Physics C 2024年第8期48卷 42-55页

作者： xuan Liu Jia-Jie Jiang Xun chen Mitsutoshi Fujita Akira Watanabe School of Nuclear Science and Technology University of South ChinaHengyang 421001China School of Mathematics and Physics University of South ChinaHengyang 421001China

Gauge/gravity duality is used to study the properties of the doubly heavy baryon(QQq)at finite rapidity and temperature in heavy-ion *** investigate the impact of rapidity on string breaking and screening of QQq and compare these effects with the results for QQ¯in *** reveal that the string-breaking distances of QQq and QQ¯are close in the confined state,and the effects of rapidity and temperature on the string breaking are not *** interesting result shows that QQq cannot be determined at sufficiently high temperatures and ***,QQ¯can exist under any conditions as long as the separation distance is sufficiently ***,the screening distances of QQq and QQ¯are compared at finite rapidity and *** on the above analysis,we infer that QQ¯is more stable than QQq at finite rapidity and temperature.

关键词： holographic QCD QGP heavy quark

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Cu_(2)Se@C thin film with three-dimensional braided structure as a cathode material for enhanced Cu^(2+) storage

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Chinese Chemical Letters 2024年第5期35卷 523-528页

作者： Wenhao chen Muxuan wu Han chen Lue Mo Yirong Zhu College of Materials and Advanced Manufacturing Hunan University of TechnologyZhuzhou 412007China Hunan Key of Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha 410022China

In the face of multiple challenges brought by the changes of global climate and environment,developing clean energy and updating green energy storage equipment are important ways to achieve carbon peak and carbon *** batteries have become a research hotspot due to their advantages of using the multivalent charge carrier,high ionic conductivity,environmental friendliness and cost *** this work,the Cu_(2)Se@C(Cu_(2)Se coated on carbon clothes)thin film with a three-dimensional braided structure is fabricated by a simple electrochemical deposition method for Cu^(2+)storage for the first *** with the commercial Cu_(2)Se powder,the well-designed Cu_(2)Se@C film shows enhanced specific capacity(640 mAh/g at 0.5 A/g)and rate performance(542 mAh/g at 5 A/g)as well as superior cycling stability(82.7%capacity retention after 1000 cycles at 1 A/g).The Cu^(2+)storage mechanism of the Cu_(2)Se@C electrode is based on a reversible phase transition process of Cu_(2)Se←→Cu_(2-x)Se←→CuSe←→CuSe_(2).In kinetic characteristic analysis,the Cu_(2)Se@C electrode demonstrates faster Cu^(2+)diffusion in discharge process than charge process resulting from the phase transition and the variation of interplanar *** work highlights a facile one-piece design strategy and opens a new gateway for the exploration of advanced aqueous energy storage systems.

关键词： Cu_(2)Se@C Cu^(2+)storage Conversion mechanism Kinetic characteristic Flexible energy storage

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Endovascular treatment of ruptured lobulated anterior communicating artery aneurysms:A retrospective study of 24 patients

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World Journal of Clinical Cases 2024年第15期12卷 2529-2541页

作者： Sheng-xuan Huang Xun-Ping Ai Ze-Hui Kang Zhi-Yong chen Ren-Man Li Zu-Chao wu Feng Zhu Department of Neurosurgery Sanming First Hospital Affiliated to Fujian Medical UniversitySanming 365000Fujian ProvinceChina

BACKGROUND Lobulated intracranial aneurysm is a special type of aneurysm with at least one additional cyst in the neck or body of the *** intracranial aneurysm is a complex aneurysm with complex morphology and structure and weak tumor wall,which is an independent risk factor for rupture and *** aneurysms located in the anterior communicating artery complex account for 36.9%of all intracranial lobular *** to its special anatomical structure,both craniotomy and endovascular treatment are more *** with single-capsule aneurysms,craniotomy for lobular intracranial aneurysms has a higher risk and complication *** To investigate the efficacy and safety of endovascular treatment for ruptured lobulated anterior communicating artery aneurysm(ACoAA).METHODS Patients with ruptured lobulated ACoAA received endovascular treatment in Sanming First Hospital Affiliated to Fujian Medical University from June 2020 to June 2022 were retrospectively *** demographic,clinical and imaging characteristics,endovascular treatment methods and follow-up results were *** A total of 24 patients with ruptured lobulated ACoAA were included,including 9 males(37.5%)and 15 females(62.5%).Their age was 56.2±8.9 years old(range 39-74).The time from rupture to endovascular treatment was 10.9±12.5 *** maximum diameter of the aneurysms was 5.1±1.0 mm and neck width were 3.0±0.7 *** patients(79.2%)were double-lobed and 5(20.8%)were ***'s grade:Grade 2 in 16 cases(66.7%),grade 3 in 6 cases(25%),and grade 4 in 2 cases(8.3%).Hunt-Hess grade:Grade 0-2 in 5 cases(20.8%),grade 3-5 in 19 cases(79.2%).Glasgow Coma Scale score:9-12 in 14 cases(58.3%),13-15 in 10 cases(41.7%).Immediately postprocedural Raymond-Roy grade:grade 1 in 23 cases(95.8%),grade 2 in 1 case(4.2%).Raymond-Roy grade in imaging follow-up for 2 wk to 3 months:grade 1 in 23 cases(95.8%),grade 2 in 1 case(4.2%).Followup for 2 to 12 months sho

关键词： Intracranial aneurysm Anterior cerebral artery Endovascular surgery Embolism Treatment outcome

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Self-Preloading Flexible Attachment Actuator with Multi-Mechanism Hierarchical Structure

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Journal of Bionic Engineering 2024年第4期21卷 1830-1846页

作者： Zhouyi Wang Qingsong Yuan Zhiyuan Weng Junsheng Yao xuan wu Lei Li Weipeng Li Yiping Feng Zhendong Dai College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics210016NanjingChina State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and Astronautics210016NanjingChina Robotics Laboratory China Nanhu Academy of Electronics and Information Technology314000JiaxingZhejiangChina

Flexible attachment actuators are popular in a wide range of applications,owing to their flexibility and highly reliable ***,their reversible adhesion performance depends on the actual effective contact area and peel angle during ***,a good actuator must ensure a uniform and reliable pre-pressure load on an adhesive surface,to increase the effective contact area of the attached surface,thereby maximizing *** study was inspired by fusion bionics for designing a hierarchical attachment structure with vacuum-adsorption and dry-adhesion *** designed structure used the normal force under the negative pressure of a suction cup as a stable source of a pre-pressure *** optimizing the rigid and flexible structural layers of the attachment structure,a load was applied uniformly to the adhesion area;thus,reliable attachment was achieved by *** structure achieved detachment by exploiting the large deformation of a pneumatic structure under a positive *** hierarchical attachment structure achieved up to 85%of the optimal performance of the adhesive *** to its self-preloading and reliable attachment characteristics,the designed structure can be used as an attachment unit in various complex scenarios,such as small,lightweight climbing platforms and the transport of objects in long,narrow pipelines.

关键词： Multi-mechanism attachment Self-preloading Hierarchical structure Adhesion Vacuum adsorption

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Simulation of RFI Cancellation Using Subspace Projection Algorithm for PAF Receiver

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Research in Astronomy and Astrophysics 2024年第1期24卷 237-244页

作者： Peng wu Jian Li Mao-Zheng chen Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

The simulation of radio frequency interference(RFI) cancellation by applying a spatial filtering technique for phased array feed(PAF) is presented. In order to better reflect the characteristics of PAF, a new signal model is to add the coupling coefficient among elements of PAF to the conventional array signal model. Then the subspace projection(SP) algorithm is used to cancel RFI from the correlation matrix of the signal, and finally, the 2D power image is drawn. The power variation of signal-of-interest direction and RFI direction before and after using the SP algorithm is analyzed. The new signal model and simulation strategy can be used to test and verify the beamformer.

关键词： methods:analytical techniques:radar astronomy telescopes

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A buffer overflow detection and defense method based on RiSC-V instruction set extension

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Cybersecurity 2024年第2期7卷 28-43页

作者： Chang Liu Yan-Jun wu Jing-Zheng wu chen Zhao Intelligent Software Research Center Institute of SoftwareChinese Academy of SciencesBejingChina University of Chinese Academy of Sciences BeijingChina State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijingChina

Buffer overflow poses a serious threat to the memory security of modern operating *** overwrites the con-tents of other memory areas by breaking through the buffer capacity limit,destroys the system execution environ-ment,and provides implementation space for various system attacks such as program control flow *** makes it a wide range of harms.A variety of security technologies have been proposed to deal with system security problems including buffer *** example,No eXecute(NX for short)is a memory management technology commonly used in Harvard *** can refuse the execution of code which residing in a specific memory,and can effectively suppress the abnormal impact of buffer overflow on control ***,in recent years,it has also been used in the field of system security,deriving a series of solutions based on NX technology,such as ExecShield,DEP,StackGuard,***,these security solutions often rely too much on the processor archi-tecture so that the protection coverage is insufficient and the accuracy is *** in the emerging system architecture field represented by RiSC-V,there is still a lack of effective solutions for buffer overflow *** the continuous rapid development of the system architecture,it is urgent to develop defense methods that are applicable to different system application environments and oriented to all executable memory spaces to meet the needs of system security ***,we propose BOP,A new system memory security design method based on RISC-V extended instructions,to build a RISC-V buffer overflow detection and defense system and deal with the buffer overflow threat in *** to this method,NX technology can be combined with program control flow analysis,and Nx bit mechanism can be used to manage the executability of memory space,so as to achieve a more granular detection and defense of buffer overflow attacks that may occur in RISC-V system

关键词： RISc-V Operating system security Buffer overflow Control flow hijacking Nx bit Xibop

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Low palladium content CeO_(2)/ZnO composite for acetone sensor with sub-second response prepared by ultrasonic method

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Journal of Central South University 2024年第7期31卷 2137-2149页

作者： chen Xu-jie XING Qiao-ling TANG xuan CAI Yong ZHANG Ming Hunan Provincial Key Laboratory of Low-dimensional Structural Physics&Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China Changsha Semiconductor Technology and Application Innovation Research Institute College of Semiconductors(College of Integrated Circuits)Hunan UniversityChangsha 410082China School of Mechanical Engineering and Mechanics Xiangtan UniversityXiangtan 411105China Research Institute of Hunan University in Chongqing Chongqing 401120China Engineering Research Center of Advanced Semiconductor Technology and Application of Ministry of Education&Key Laboratory for Micro-/Nano-Optoelectronic Devices of Ministry of Education National Key Laboratory of Power Semiconductor and Integration TechnologyCollege of Semiconductors(College of Integrated Circuits)Hunan UniversityChangsha 410082China

In practical applications,noble metal doping is often used to prepare high performance gas sensors,but more noble metal doping will lead to higher preparation *** this study,CeO_(2)/ZnO-Pd with low palladium content was prepared by ultrasonic method with fast response and high selectivity for acetone *** the same amount of palladium added,the selectivity coefficient of CeO_(2)/ZnO-Pd is 1.88 times higher than that of the stirred *** with the pure PdO-doped CeO_(2)/ZnO-PdO material,the content of Pd in CeO_(2)/ZnO-PdO is about 30%of that in CeO_(2)/ZnO-PdO,but the selectivity coefficient for acetone is 2.56 times *** CeO_(2)/ZnO-Pd sensor has a higher response(22.54)to 50×10^(−6) acetone at 300℃and the selectivity coefficient is 2.57 times that of the CeO_(2)/ZnO *** sensor has a sub-second response time(0.6 s)and still has a 2.36 response to 330×10^(−9) of *** doping makes Pd particles smaller and increases the contact area with ***,the composition of n-p-n heterojunction and the synergistic effect of Pd/PdO improve the sensor *** shows that ultrasonic Pd doping provides a way to improve the utilization rate of doped metals and prepare highly selective gas sensors.

关键词： low palladium sub-second responce ultrasonic method acetone sensor heterojunction

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Stratigraphic framework and sedimentary evolution during the Cryogenian-Ediacaran transition in northeastern Sichuan Basin,South China

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Petroleum Science 2024年第2期21卷 823-835页

作者： Yi Zhang Hong-Wei Kuang Yong-Qing Liu Qiang Shi Dong-Ge Wang Ke-Ning Qi Yu-Chong Wang Da-Wei Qiao Xiao-Shuai chen Li-Zhi wu Meng Tian Long chen Yi Wei Liao-Yuan Song Jian Li Zi-Gang wu Yun-Qian Liu xuan-Chun Liu An-Qing chen Zhi-Wei Liao Institute of Geology Chinese Academy of Geological SciencesBeijing100037China State Key Laboratory of Coal Mine Disaster Dynamics and Control School of Resources and Safety EngineeringChongqing UniversityChongqing400044China No.205 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing401121China Chongqing Institute of Geological Survey Chongqing401122China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu610059SichuanChina

The northeastern Sichuan area in the northern Yangtze margin has unique Ediacaran geological records,especially the Doushantuo Formation(DST),and become a hot research area in recent ***,the Cryogenian-Ediacaran(C-E)boundary has not been precisely identified,which restricts the in-depth study of geological information during this crucial transitional period and is unfavorable for a systematic and complete understanding of the Yangtze Block and even the global paleogeographic *** study conducted stratigraphy,sedimentology,and chronostratigraphy to establish the stratigraphic framework and sedimentary evolution of the C-E transition strata in northeastern *** results showed that the Ediacaran sediments,without the cap dolomite,unconformably overlaid the Cryogenian sediments in the studied *** Member II of the DST,characterized by 50-160 m of red-green sandstone(approximately equivalent to the original chengkou“Guanyinya Formation”),directly overlaid the Cryogenian sediments and displayed a 623±2.3 Ma maximum depositional age from the detrital zircon U-Pb *** stratigraphic correlations indicate that the C-E transition strata in northeastern Sichuan had a consistent lithological association and sedimentary sequence characteristics but differed from the Three ***,the upper Nantuo massive glacial diamictites transition to the icebergs rafted lonestone-bearing mudstones at the top,then change upward to DST barrier coast *** proposed DST of the northeastern Sichuan Basin was divided into three lithostratigraphic members without the regional Member I cap dolomite:(i)Member II purple-red,gray-green sandstone strata,(ii)MemberⅢblack mudstone strata,and(iii)Member IV P-Mn bearing *** the C-E transition,the study area experienced(i)the global deglaciation stage in the terminal Marinoan glaciation and(ii)the filling-leveling up stage with clastic rocks in the early ***,the early Ediacaran

关键词： Marinoan glaciation Doushantuo formation Cap dolomite Deglacial and coastal deposits Detrital zircon U-Pb dating

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Surface demineralized freeze-dried bone allograft followed by reimplantation in a failed mandibular dental implant

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Regenerative Biomaterials 2024年第1期3卷 82-93页

作者： Jing Zhang Jie Wang Jiayi You xuan Qin Huimin chen Xiantong Hu Yantao Zhao Yang Xia Jiangsu Key Laboratory of Oral Diseases Nanjing Medical UniversityNanjingJiangsu 210029PR China Jiangsu Province Engineering Research Center of Stomatological Translational Medicine Nanjing Medical UniversityNanjingJiangsu 210029PR China Department of Restorative Dental Sciences Faculty of DentistryThe University of Hong KongHong Kong SARPR China Senior Department of Orthopedics The Fourth Medical Center of PLA General HospitalBeijing100048PR China Beijing Engineering Research Center of Orthopedics Implants Beijing 100048PR China State Key Laboratory of Military Stomatology Xi'an 710032PR China

The removal of a failed implant with high torque causes significant damage to the surrounding tissue,compromising bone regeneration and subsequent osseointegration in the defect ***,we report a case of carrier screw fracture followed by immediate implant removal,bone grafting and delayed reimplantation.A dental implant with a fractured central carrier screw was removed using the bur-forceps *** resulting three-wall bone defect was filled with granular surface demineralized freeze-dried bone allograft(SD-FDBA).Cone-beam computerized tomography was performed at 1week,6months and 15months postoperatively and standardized for quantitative *** alveolar bone width and height at 15months post-surgery were about 91%of the original values,with a slightly lower bone density,calculated using the gray value *** graft site was reopened and was found to be completely healed with dense and vascularized bone along with some residual bone *** followed by restoration was performed 8months *** quality of regenerated bone following SD-FDBA grafting was adequate for osseointegration and longterm implant *** excellent osteogenic properties of SD-FDBA are attributed to its human origin,cortical bone-like structure,partly demineralized surfaces and bone morphogenetic protein-2-containing *** investigation with more cases and longer follow-up was required to confirm the final clinical effect.

关键词： dental implant implant failure allogeneic bone bone regeneration reimplantation

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