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Heteroatom doping regulates the catalytic performance of singleatom catalyst supported on graphene for ORR

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Nano Research 2024年第3期17卷 1086-1093页

作者： Ji-Kai Sun Yu-wei pan Meng-Qian xu Lei Sun Shaolong Zhang wei-Qiao Deng Dong Zhai Institute of Molecular Sciences and Engineering Institute of Frontier and Interdisciplinary ScienceShandong UniversityQingdao 266237China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Replacing fossil fuels with fuel cells is a feasible way to reduce global energy shortages and environmental pollution.However,the oxygen reduction reaction(ORR)at the cathode has sluggish kinetics,which limits the development of fuel cells.It is significant to develop catalysts with high catalytic activity of ORR.The single-atom catalysts(SACs)of Pt supported on heteroatom-doped graphene are potential candidates for ORR.Here we studied the SACs of Pt with different heteroatoms doping and screened out Pt-C_(4) and Pt-C_(3)O_(1) structures with only 0.13 V overpotential for ORR.Meanwhile,it is found that B atoms doping could weaken the adsorption capacity of Pt,while N or O atoms doping could enhance it.This regularity was verified on Fe SACs.Through the electronic interaction analysis between Pt and adsorbate,we explained the mechanism of this regularity and further proposed a new descriptor named corrected d-band center(ε_(d-corr))to describe it.This descriptor is an appropriate reflection of the number of free electrons of the SACs,which could evaluate its adsorption capacity.Our work provides a purposeful regulatory strategy for the design of ORR catalysts.

关键词： single-atom catalyst(SAC) oxygen reduction reaction(ORR) heteroatom doping corrected d-band center descriptor

Primary frequency control considering communication delay for grid-connected offshore wind power systems

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Global Energy Interconnection 2024年第3期7卷 241-253页

作者： xueping pan Qijie xu Tao xu Jinpeng Guo Xiaorong Sun Yuquan Chen Qiang Li wei Liang School of Electrical and Power Engineering Hohai UniversityNanjing 211100P.R.China Electric Power Research Institute of State Grid Jiangsu Electric Power Co.Ltd Nanjing 211103P.R.China

Offshore wind farms are becoming increasingly distant from onshore centralized control centers,and the communication delays between them inevitably introduce time delays in the measurement signal of the primary frequency control.This causes a deterioration in the performance of the primary frequency control and,in some cases,may even result in frequency instability within the power system.Therefore,a frequency response model that incorporates communication delays was established for power systems that integrate offshore wind power.The Padéapproximation was used to model the time delays,and a linearized frequency response model of the power system was derived to investigate the frequency stability under different time delays.The influences of the wind power proportion and frequency control parameters on the system frequency stability were explored.In addition,a Smith delay compensation control strategy was devised to mitigate the effects of communication delays on the system frequency dynamics.Finally,a power system incorporating offshore wind power was constructed using the MATLAB/Simulink platform.The simulation results demonstrate the effectiveness and robustness of the proposed delay compensation control strategy.

关键词： Offshore wind power Primary frequency control Time delay Padéapproximation Time-delay compensation control

Greening the Belt and Road Initiative: Evidence from emergy evaluation of China’s provincial trade with ASEAN countries

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Fundamental Research 2024年第2期4卷 379-393页

作者： xu Tian Joseph Sarkis wei Chen Yong Geng Haozhi pan Zuoxi Liu Sergio Ulgiati SJTU-UNIDO Joint Institute of Inclusive and Sustainable Industrial Development School of International and Public AffairsShanghai Jiao Tong UniversityShanghai 200030China Worcester Polytechnic Institute Worcester MA 01609-2280USA School of Geography and Environment Shandong Normal UniversityJinan 250358China School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai 200030China Key Laboratory of Clean Energy of Liaoning School of Energy and EnvironmentShenyang Aerospace UniversityShenyang 110136China Department of Science and Technology Parthenope University of NapoliNaples 80143Italy School of Environment Beijing Normal UniversityBeijing 100875China

The Belt and Road Initiative(BRI)is a central policy within China’s regional development and foreign trade strategy.Traditional trade has typically depended on economic valuation of resources,while the embedded environmental value is rarely considered.This situation exists in most BRI trade evaluations.To address BRI environmental sustainability issues,we consider the role of pivotal Chinese provinces and their key trade partners(ASEAN countries)as an illustration for the environmental value of resource exchanges.Emergy accounting is used as the valuation tool for a sample period of seventeen years.Key results include:(1)Emergy valuations show sustainability of sample provinces decreased over time;(2)ASEAN countries such as Indonesia,Malaysia,Singapore,Thailand,and Vietnam play significant resource roles for provincial economic systems;(3)Diverse trends in trade between pivotal provinces and ASEAN countries resulted in an unbalanced trade structure from trade.Policy implications are proposed to promote a more globally sustainable and fair trade using BRI as an established trade policy.

关键词： International trade Emergy Belt and road initiative Environmental sustainability Province

Design strategies of high-performance lead-free electroceramics for energy storage applications

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Rare Metals 2024年第3期43卷 853-878页

作者： Biao Guo Fei Jin Li Li Zi-Zhao pan Xin-wei xu Hong Wang Department of Materials Science and Engineering College of EngineeringSouthern University of Science and TechnologyShenzhen518055China School of Microelectronics and State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049China

A greater number of compact and reliable electrostatic capacitors are in demand due to the Internet of Things boom and rapidly growing complex and integrated electronic systems,continuously promoting the development of high-energy-density ceramic-based capacitors.Although significant successes have been achieved in obtaining high energy densities in lead-based ferroelectric ceramics,the utilization of lead-containing ceramies has been restricted due to environmental and health hazards of lead.Lead-free ferroelectric ceramics have garnered tremendous attention and are expected to replace lead-based ceramics in the near future.However,the energy density of lead-free ceramics is still lagging behind that of lead-containing cou.nterparts,severely limiting their applications.Significant efforts have been made to enhance the energy storage performance of lead-free ceramics using multi-scale design strategies,and exciting progress has been achieved in the past decade.This review briefly discusses the energy storage mechanism and fundamental characteristics of a dielectric capacitor,summarizes and compares the state-of-the-art design strategies for high-energy-density lead-free ceramics,and highlights several critical issues and requirements for industrial production.The prospects and challenges of lead-free ceramics for energy storage applications are also discussed.

关键词： Dielectric materials Lead-free ceramic Environment friendly Energy storage Design strategy

Pig pangenome graph reveals functional features of non‑reference sequences

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Journal of Animal Science and Biotechnology 2024年第3期15卷 956-970页

作者： Jian Miao Xingyu wei Caiyun Cao Jiabao Sun Yuejin xu Zhe Zhang Qishan Wang Yuchun pan Zhen Wang College of Animal Sciences Zhejiang UniversityHangzhou 310058ZhejiangChina Yazhou Bay Science and Technology City Hainan Institute of Zhejiang UniversityYazhou DistrictBuilding 11Yongyou Industrial ParkSanya 572025HainanChina

Background The reliance on a solitary linear reference genome has imposed a significant constraint on our compre-hensive understanding of genetic variation in animals.This constraint is particularly pronounced for non-reference sequences(NRSs),which have not been extensively studied.Results In this study,we constructed a pig pangenome graph using 21 pig assemblies and identified 23,831 NRSs with a total length of 105 Mb.Our findings revealed that NRSs were more prevalent in breeds exhibiting greater genetic divergence from the reference genome.Furthermore,we observed that NRSs were rarely found within coding sequences,while NRS insertions were enriched in immune-related Gene Ontology terms.Notably,our investigation also unveiled a close association between novel genes and the immune capacity of pigs.We observed substantial differences in terms of frequencies of NRSs between Eastern and Western pigs,and the heat-resistant pigs exhibited a substantial number of NRS insertions in an 11.6 Mb interval on chromosome X.Additionally,we discovered a 665 bp insertion in the fourth intron of the TNFRSF19 gene that may be associated with the ability of heat tolerance in South-ern Chinese pigs.Conclusions Our findings demonstrate the potential of a graph genome approach to reveal important functional features of NRSs in pig populations.

关键词： Heat tolerance Immune ability Non-reference sequences Pig pangenome

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Identification of missing CYP450 enzymes involved in paclitaxel biosynthesis and heterologous reconstitution of baccatin III

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Chinese Journal of Natural Medicines 2024年第4期22卷 291-292页

作者： DU Jinfa LIAO pan LU xu State Key Laboratory of Natural Medicines School of Traditional Chinese PharmacyChina Pharmaceutical UniversityNanjing 210009China Department of Biology Hong Kong Baptist UniversityKowloon TongHong KongChina State Key Laboratory of Agrobiotechnology The Chinese University of Hong KongHong KongChina State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs Beijing 100700China Medical Botanical Garden China Pharmaceutical UniversityNanjing 210009China

Paclitaxel,a tetracyclic diterpenoid,has garnered attention for its potent anti-cancer properties and intricate molecular structure,making it a significant target for chemical synthesis and biosynthesis[1].However,its natural sources are extremely limited,as it is derived exclusively from the bark of endangered genus Taxus plants,which contain paclitaxel in very low concentrations(0.01%−0.05%)[2-3].Recent advances in synthetic biology present promising opportunities to enhance paclitaxel levels in Taxus cell cultures or to enable the reconstitution of its production in heterologous hosts,such as yeast or tobacco(Nicotiana benthamiana).

关键词： Paclitaxel biosynthesis Baccatin III Cytochrome P450 Taxane oxetanase 1 Heterologous reconstitution

Activatable fluorescent probes for imaging and diagnosis of rheumatoid arthritis

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Military Medical Research 2024年第2期11卷 287-307页

作者： pan Luo Fu-Qiang Gao wei Sun Jun-You Li Cheng Wang Qing-Yu Zhang Zhi-Zhuo Li Peng xu Department of Joint Surgery Honghui HospitalXi'an Jiaotong UniversityXi'an 710054China Department of Orthopedics China-Japan Friendship HospitalBeijing 100029China Department of Orthopaedic Surgery of the Perelman School of Medicine University of PennsylvaniaPhiladelphiaPA 19104USA School of Mechanical Engineering Sungkyunkwan UniversitySuwon 16419South Korea Department of Orthopaedic Surgery Peking University Third HospitalPeking UniversityBeijing 100191China Department of Orthopedics Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021China State Key Laboratory of Pharmaceutical Biotechnology Division of Sports Medicine and Adult Reconstructive SurgeryDepartment of Orthopedic SurgeryNanjing Drum Tower Hospitalthe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008China

Rheumatoid arthritis(RA)is a systemic autoimmune disease that is primarily manifested as synovitis and polyarticular opacity and typically leads to serious joint damage and irreversible disability,thus adversely affecting locomotion ability and life quality.Consequently,good prognosis heavily relies on the early diagnosis and effective therapeutic monitoring of RA.Activatable fluorescent probes play vital roles in the detection and imaging of biomarkers for disease diagnosis and in vivo imaging.Herein,we review the fluorescent probes developed for the detection and imaging of RA biomarkers,namely reactive oxygen/nitrogen species(hypochlorous acid,peroxynitrite,hydroxyl radical,nitroxyl),pH,and cysteine,and address the related challenges and prospects to inspire the design of novel fluorescent probes and the improvement of their performance in RA studies.

关键词： Rheumatoid arthritis Fluorescent probe Imaging Diagnosis Biomarker

The Al_(2)O_(3)and Mn/Al_(2)O_(3)sorbents highly utilized in destructive sorption of NF_(3)

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Chinese Journal of Chemical Engineering 2024年第1期65卷 54-62页

作者： Yanfei pan Hejian Li Li Zheng Xiufeng xu School of Chemistry and Chemical Engineering Yantai UniversityYantai 264005China

NF_(3)is commonly used as an etching and cleaning gas in semiconductor industry,however it is a strongly greenhouse gas.Therefore,the destruction of disposal NF_(3)is an urgent task to migrate the greenhouse effect.Among the technologies for NF_(3)abatement,the destructive sorption of NF_(3)over metal oxides sorbents is an effective way.Thus,the search for a highly reactive and utilized sorbent for NF_(3)destruction is in great demand.In this work,AlOOH supported on carbon-sphere(AlOOH/CS)as precursors were synthesized hydrothermally and heat-treated to prepare the Al_(2)O_(3)sorbents.The influence of AlOOH/CS hydrothermal temperatures on the reactivity of derived Al_(2)O_(3)sorbents for NF_(3)destruction was investigated,and it is shown that the Al2O3 from AlOOH/CS hydro-thermalized at 120℃is superior to others.Subsequently,the optimized Al_(2)O_(3)was covered by Mn(OH)x to prepare Mn/Al_(2)O_(3)sorbents via changing hydrothermal temperatures and Mn loadings.The results show that the Mn/Al_(2)O_(3)sorbents are more utilized than bare Al_(2)O_(3)in NF_(3)destructive sorption due to the promotional effect of Mn_(2)O_(3)as surface layer on the fluorination of Al_(2)O_(3)as substrate,especially the optimal 5%Mn/Al2O3(160℃)exhibits a utilization percentage as high as 90.4%,and remarkably exceeds all the sorbents reported so far.These findings are beneficial to develop more efficient sorbents for the destruction of NF_(3).

关键词： Greenhouse gas NF_(3)destructive sorption Sorbents Al_(2)O_(3) Mn/Al_(2)O_(3) Reactivity

Flow Field Simulation and Parameter Analysis of Hydraulic Unbalanced Bionic Self-recovery Actuator for Rotary Equipment

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Journal of Bionic Engineering 2024年第1期21卷 325-343页

作者： wei Li Xin pan Dehong Ge Jinji Gao Key Laboratory of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of High-End Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China

The rotor is the most important component of rotating machinery,and the vibration produced by its mass unbalance has a serious influence on the secure and steady operation of the machine,so an effective online suppression technology is urgently needed.A new hydraulic unbalanced bionic self-recovery system is introduced,imitating the way of manually repairing faulty equipment.To accomplish the effect of actuator mass redistribution,the technology employs pressurized air to drive the quantitative transfer of liquid in the reservoir cavity at opposite positions.It can complete the online adjustment of the equipment's balancing state and suppress the unbalanced vibration of equipment in real time,which gives the equipment the ability to maintain an autonomous health state and improve equipment performance.The composition and working principle of the system are introduced in detail,and the key performance parameters,such as the minimum running speed and the balancing liquid transfer speed,are analyzed theoretically.The fluid-solid coupling model of the actuator was established,and the two-phase flow from inside the hydraulic unbalanced bionic self-recovery actuator was simulated under multiple working conditions and the performance parameters were quantitatively analyzed.A balancing simulation test bed was built,and its effectiveness was verified by performance parameter tests and unbalanced bionic self-recovery experiments.The experimental results show that the mass distribution adjustment of the balancing disk can be achieved using different viscosity balancing liquid,and the response of liquid viscosity 10 cSt is faster than that of liquid viscosity 100 cSt in the process of balancing liquid transfer,and the time is reduced by more than 75%;the system can reduce the simulated rotor amplitude from 18.3μm to 10.6μm online in real time,which provides technical support for the subsequent development of a new generation of bionic intelligent equipment.

关键词： Engineering self-recovery-Bionics Simulation analysis Self-recovery regulation