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China Foundry 2024年第3期21卷 205-212页

作者： Guan-yu jiang Meng-wu wu Xiao-guang Yang Hui Wang yu-yuan Zhu Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina Wescast Industries(China)Co. Ltd.Wuhan 430100China

Three types of steels were designed on the basis of GX40CrNiSi25-12 austenitic heat resistant steel by adding different Mn contents(2wt.%,6wt.%,and 12wt.%).Thermodynamic calculation,microstructure characterization and mechanical property tests were conducted to investigate the effect of Mn addition on the microstructure and mechanical properties of the austenitic heat resistant *** show that the matrix structure in all the three types of steels at room temperature is completely *** NbC and M_(23)C_(6)precipitate at grain boundaries of austenite *** the increase of Mn content,the number of carbides increases and their distribution becomes more *** the Mn content increases from 1.99%to 12.06%,the ultimate tensile strength,yield strength and elongation increase by 14.6%,8.0%and 46.3%,*** improvement of the mechanical properties of austenitic steels can be explained by utilizing classic theories of alloy strengthening,including solid solution strengthening,precipitation strengthening,and grain *** increase in alloy strength can be attributed to solid solution strengthening and precipitation strengthening caused by the addition of *** improvement of the plasticity of austenitic steels can be explained from two aspects:grain refinement and homogenization of precipitated phases.

关键词： austenitic heat resistant steel manganese microstructure mechanical properties

A High-Linear Radio Frequency Quadrature Modulator with Improved Sideband Suppression and Carrier Leakage Performance

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Tsinghua Science and Technology 2024年第3期29卷 635-643页

作者： Yingdan jiang Zongguang yu Shutong wu Li Li Xuelian Liu School of Electronic Science and Engineering Nanjing UniversityNanjing 210093China The 58th Research Institute of China Electronic Technology Group Corporation Wuxi 214072China

The quadrature modulator is a crucial block in transmitters that upconverts baseband signals to theRadio Frequency(RF)band of interest using local oscillator *** this paper,non-ideal factors thatinfluence the performance of the quadrature modulator are considered,and solutions are accordingly taken inthe quadrature modulator design.A high-linear RF quadrature modulator with improved sideband suppressionand carrier leakage performance is presented in this *** quadrature modulator implemented in the0.18-μm SiGe process uses the current bleeding technique to improve the general performance of the doublebalanced active Gilbert *** on-chip prescaler followed by two cascaded limiting amplifiers is designed toprovide accurate quadrature local oscillator *** at quadrature baseband signal input ports areproposed to eliminate DC *** measured sideband suppression achieves a performance of better than−43 dBc and carrier leakage is less than−38 dBm over the output RF frequency range of 30 MHz to 2.15 *** output 1 dB compression point equals 11.4 dBm at 800 MHz.

关键词： Radio Frequency(RF) quadrature modulator sideband suppression carrier leakage linearity

Effects of hot deformation and in-situ ZrB2 particle on microstructure and tensile performance of AA7085 composite sheets

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1778-1791页

作者： jiang-jing wu Xi-zhou Kai Chuang Guan yu-tao Zhao School of Material Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

To provide a new idea to reduce anisotropy for sheets in the thickness direction by microstructure modification and,mean-while,maintain or even enhance tensile performance,the in-situ ZrB2 particle/AA7085 composite sheets with thicknesses of 1,2,3,and 6 mm were *** as-cast grain size was significantly refined by the heterogeneous nucleus of the ZrB2 *** microstructure results show that severe hot deformation converts as-cast disordered microstructure into a sequential microstructure by crushing the remanent phases and matrix into a fiber *** the solid solution and aging heat treatment,the composite sheets exhibit largely recrystallized grains compared with partially recrystallized grains in the matrix sheets,and weak or even free texture exists in the *** grain size in the composite sheets decreases with the increase in thickness *** the thickness range of 1-3 mm,the composite sheets maintain a similar tensile per-formance as that in matrix sheets,while the strength and ductility in the 6-mm-thick composite sheet are improved.

关键词： Composite sheet Grain structure Texture Dislocation Strengthening

Prediction of chemical short-range order in high-/medium-entropy alloys

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Journal of Materials Science & Technology 2024年第2期169卷 115-123页

作者： Pei-yu Cao Jing Wang Ping jiang yun-jiang Wang Fu-Ping yuan Xiao-Lei wu State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of ScienceBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Chemical short-range orders(CSROs),as the built-in sub-nanoscale entities in a high-/medium-entropy alloy(H/MEA),have aroused an ever-increasing *** multi-principal elements in an H/MEA to form a complex concentrated solution,a variety of sub-systems of species exist to induce the metastable ordered compounds as candidates for ultimate *** issues remain pending on the origin of CSROs as to how to judge if CSRO will form in an H/MEA and particularly,what kind of CSROs would be stably produced if there were multiple ***,the first-principles method,along with the proposed local formation energy calculation in allusion to the atomic-scale chemical heterogeneities,is used to predict the CSRO formation based on the mechanical stability,thermodynamic formation energy,and electronic *** simulations are detailed in an equiatomic ternary VCoNi MEA with three kinds of potential compounds,i.e.,L1_(1),L1_(2),and B2,in the face-centered cubic *** turns out that L1_(1)is stable but hard to grow up so as to become the final CSRO.L1_(1)is further predicted as CSROs in CrCoNi,but unable to form in FeCoNi and CrMnFeCoNi *** predictions are consistent with the experimental *** findings shed light on understanding the formation of *** method is applicable to other H/MEAs to design and tailor CSROs by tuning chemical species/contents and thermal processing for high performance.

关键词： Short-range order High-entropy alloy Microstructure First-principles calculation Gibbs free energy Local electronic density of states

Status and trends of carbon emissions research at the county level in China

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Advances in Climate Change Research 2024年第2期15卷 338-352页

作者： Ang-Zu CAI Ru GUO yu-Hao ZHANG jiang wu College of Environmental Science and Engineering Institute of Environmental Planning and ManagementTongji UniversityShanghai 200092China Institute of Carbon Neutrality Tongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China College of Architecture and Urban Planning Tongji UniversityShanghai 200092China Megacity Elaborated Urban Governance Institute Tongji UniversityShanghai 200092China

This study provides a comprehensive overview of the challenges to achieving carbon neutrality at the county level in China and offers targeted recommendations,laying the groundwork for future specialized research in this area.A total of 283 relevant studies(2004-2023)were analyzed to assess county-level carbon emissions through three phases:bibliometric analysis,frontier analysis,and future *** findings reveal that publication trends were largely influenced by domestic and foreign *** cluster discerns ten primary themes,ranging from conceptual frameworks to research *** frontier analysis of the literature highlights the leading research areas,which include carbon neutrality pathway,driving factors,spatiotemporal variation of carbon emissions,the co-effects of pollutants and carbon reduction,and carbon emissions in China's rural *** from the results of bibliometric and frontier analyses,this study elucidates the recommendations for achieving carbon neutrality at the county level from three perspectives:effective regional policy guidance,emphasis on ecological conservation,and the deployment of advanced carbon reduction and sequestration *** study enriches the body of knowledge on carbon emissions at the county level and holds significant implications for China's comprehensive push towards achieving its carbon neutrality objectives.

关键词： Carbon emissions Emission reduction County Carbon neutrality Sustainability

Highly Aligned Graphene Aerogels for Multifunctional Composites

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Nano-Micro Letters 2024年第6期16卷 276-342页

作者： Ying wu Chao An Yaru Guo Yangyang Zong Naisheng jiang Qingbin Zheng Zhong‑Zhen yu Beijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004People’s Republic of China School of Science and Engineering The Chinese University of Hong KongShenzhenShenzhenGuangdong 518172People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Stemming from the unique in-plane honeycomb lattice structure and the sp^(2)hybridized carbon atoms bonded by exceptionally strong carbon–carbon bonds,graphene exhibits remarkable anisotropic electrical,mechanical,and thermal *** maximize the utilization of graphene’s in-plane properties,pre-constructed and aligned structures,such as oriented aerogels,films,and fibers,have been *** unique combination of aligned structure,high surface area,excellent electrical conductivity,mechanical stability,thermal conductivity,and porous nature of highly aligned graphene aerogels allows for tailored and enhanced performance in specific directions,enabling advancements in diverse *** review provides a comprehensive overview of recent advances in highly aligned graphene aerogels and their *** highlights the fabrication methods of aligned graphene aerogels and the optimization of alignment which can be estimated both qualitatively and *** oriented scaffolds endow graphene aerogels and their composites with anisotropic properties,showing enhanced electrical,mechanical,and thermal properties along the alignment at the sacrifice of the perpendicular *** review showcases remarkable properties and applications of aligned graphene aerogels and their composites,such as their suitability for electronics,environmental applications,thermal management,and energy *** and potential opportunities are proposed to offer new insights into prospects of this material.

关键词： Highly aligned graphene aerogels Quantitative characterization of alignment Multifunctional composites Anisotropic properties Multifunctional applications

Elucidating and manipulating pressure-induced water intrusion–extrusion in tunable hydrophobic Co/Zn bimetallic ZIFs:Roles of pore size and hydrogen bond

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Nano Research 2024年第1期17卷 344-353页

作者： Diyi Fang Chuanlei Liu yu Chen Qilong Peng Kongguo wu yuxiang Chen Hao jiang yuan wu Benxian Shen Qiumin wu Di wu Hui Sun International Joint Research Center of Green Energy Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Alexandra Navrotsky Institute for Experimental Thermodynamics The Gene and Linda Voiland School of Chemical Engineering and BioengineeringMaterials Science and Engineeringand Department of ChemistryWashington State UniversityWashington 99163USA

Porous heterogeneous lyophobic systems(HLSs)find potential applications in energy restoring,dissipating,and ***,the development of controllable HLSs still lacks rational structure design of nanoporous materials matching the molecular sizes of adopted *** that,thoroughly understanding the underlying transportation mechanism in the confined nano channels is greatly *** this work,a series of Co/Zn bimetallic zeolitic imidazolate frameworks(ZIFs)with tunable structures were synthesized via regulating the Co to Zn ratios and employed to investigate the intrusion–extrusion of liquid water in confined *** characterizations confirm the heterometallic coordination in the Co/Zn-doped *** intrusion–extrusion experiments unlock the relationship between the intrusion pressure and the nanopore size and realize the evolution of the HLSs between molecular spring and *** addition,cycling tests indicate the reversible structure change of Co/Zn ZIFs encountering pressure-induced water *** combination with molecular dynamics simulations,we present that the water multimers intrude into nanopores of ZIFs in chain-like forms along with dissociation of hydrogen bonds(HBs).Water molecules in the pre-intrusion state exhibit reduced HBs in response to the increase of pressure and linear structure with 1.6–3.0 HBs on *** transition to the post-intrusion situation,the associative configuration of water tends to exhibit the tetrahedral ***,we highlight the roles of pore size and HB in synergically dominating the pressure-induced intrusion–extrusion of liquid water in hydrophobic ***,the present work can also guide the development of functional guest–host systems based on porous architectures.

关键词： heterometallic zeolitic imidazolate frameworks nanopore intrusion hydrogen bonds

PACS gene family-related neurological diseases: limited genotypes and diverse phenotypes

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World Journal of Pediatrics 2024年第1期20卷 82-91页

作者： Han Zhang Kai Gao Shuang Wang yue-Hua Zhang Zhi-Xian Yang Ye wu yu-wu jiang Department of Pediatrics Peking University First Hospital.No.1 Xi'an Men StreetWest DistrictBeijing 100034China Bejing Key Laboratory of Molecular Diagnosis and Study on Pediatric Genetic Diseases BeijingChina Children Epilepsy Center Peking University First HospitalBeijingChina Key Laboratory for Neuroscience Ministry of Education/National Health and Family Planning CommissionPeking UniversityBeijingChina Center of Epilepsy Beijing Institute for Brain DisordersBeijingChina

Background The PACS gene family has been demonstrated to be related to intracellular vesicular *** phenotypic manifestations caused by the pathogenic variants of PACS include epilepsy,intellectual disability/developmental delay,and malformations,such as facial *** We identified seven new cases with pathogenic or likely pathogenic PACS variants using next-generation *** information obtained from these patients was analyzed along with that obtained from previously reported *** With the inclusion of the newly diagnosed cases in this study,103 cases with PACS gene family-related neurological diseases were reported,of which 43 were PACS2-related cases and the remaining were PACSI-related *** patients had seizures,which have been reported to be effectively controlled by several types of anti-seizure medications(ASMs).The most efficacious and frequently prescribed ASMs included sodium valproate(43.3%,13/30),oxcarbazepine/carbamazepine(26.7%,8/30),and levetiracetam(20%,6/30).Almost all patients had intellectual disability/developmental *** most common pathogenic missense variants were PACSI ***203Trp and PACS2 *** addition,we report a patient carrying a likely pathogenic copy number variation(CNV)(de novo heterozygous deletion of chr14:105821380-106107443,286 kilobase,destroyed part of the furin-binding region domain and the protein structure after it)with more severe and refractory late-onset *** The clinical phenotypes of the different PACS heterozygous missense variants were *** pathogenic variant sites of PACSI and PACS2 were quite limited but located in different regions.A CNV destroying part of the PACS2 gene might also be *** findings may provide an important clue for further functional studies on the pathogenic mechanism of neurological disorders related to the PACS gene family.

关键词： Developmental delay Epilepsy Intellectual disability PACSI PACS2

Enhancing the Circularly Polarized Luminescence of Self-assembled Cyanostilbenes through Extended π-Conjugation

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Chinese Journal of Chemistry 2024年第2期42卷 135-141页

作者： Tongjin Lv Song wu yu Jin Jianfei Ma Sixun jiang yuncong Xue Feng Wang Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefeiAnhui 230026China Department of Thoracic Surgery Shanghai Jiao Tong University Affiliated Sixth People's HospitalShanghai 200233China

Chiral supramolecular assembly of π-conjugated luminophores provides a promising avenue for enhancing circularly polarized *** this study,we shed light on the impact of π-conjugation length on circularly polarized luminescent performance of the resulting supramolecular assemblies,by designing a tetra-cyanostilbene monomeric compound alongside two dicyanostilbene control *** cyanostilbene-based compounds possess the ability to form chiral supramolecular polymers in toluene,driven by a synergistic combination of intermolecular hydrogen bonding and π-stacking *** extended π π-aromatic skeleton brings bathochromic-shifted fluorescence and enhanced intermolecular stacking capability for the tetra-cyanostilbene ***,chiral supramolecular assemblies formed by the tetra-cyanostilbene compound demonstrate a remarkable two-fold increase in g_(lum) values relative to the assemblies formed by the dicyanostilbene ***,this study provides valuable insights into the relationship between-conjugation length and the circularly polarized luminescent performance of π-conjugatedsupramolecularassemblies.

关键词： Self-assembly Supramolecular polymer Supramolecular chirality Circularly polarized luminescence Cyanostilbene πInteractions Aggregation Nanostructures

Experimental and numerical study on atmospheric-pressure air dielectric barrier discharge via 50 Hz/5000 Hz dual-frequency excitation

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High Voltage 2024年第2期9卷 391-402页

作者： Junwen He Bangfa Peng Guanglin yu Ronggang Wang Nan jiang Jie Li Yan wu School of Electrical Engineering Dalian University of TechnologyDalianChina Canmax Technologies Co. Ltd.SuzhouChina

A dual-frequency(DF)dielectric barrier discharge,excited by the superposition of a 50 Hz low frequency(LF)and a 5000 Hz intermediate frequency(IF),is proposed to enhance *** effect of the LF voltage component on the breakdown behaviour of the DF discharge during different periods has been studied both experimentally and *** number of high-current pulses rises as the LF voltage *** statistical analysis shows that the number of the current pulse amplitude above 80 mA in the DF discharge reaches nearly 6 times that in the IF ***,the total discharge energy in the DF discharge is significantly higher than that in the IF *** simulation re-produces the temporal variation of the breakdown behaviours in the DF *** simulated results reveal that the maximal electric field strength of the breakdown process is greater in the DF discharge compared to the IF discharge during a half-period of ***,the comparison between the IF and DF discharges exhibits that the LF voltage regulates the accumulation of residual charged species on the dielectric surface after the breakdown by modulating the residual voltage between the air gap.

关键词： dielectric excitation excited