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Opportunities for production and property research of neutron-rich nuclei around N=126 at HIAF

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Nuclear Science and Techniques 2024年第6期35卷 101-113页

作者： Shao-Bo Ma Li-Na Sheng xue-heng Zhang Shi-Tao Wang Kai-Long Wang Chun-Wang Ma Hool-Jin ong zhi-Yu Sun Shu-Wen Tang Yu-Hong Yu xin-Tong Du xiao-Bao Wei Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516000China University of Chinese Academy of Sciences Beijing 100049China College of Physics Henan Normal UniversityXinxiang 453007China Institute of Nuclear Science and Technology Henan Academy of ScienceZhengzhou 450046China Joint-Department for Nuclear Physics Lanzhou University and Institute of Modern PhysicsLanzhou 730000China Research Center for Nuclear Physics Osaka UniversityOsaka 567-0047Japan RIKEN Nishina Center Saitama 351-0198Japan Northwest Normal University Lanzhou 730070China

The study of nuclide production and its properties in the N=126 neutron-rich region is prevalent in nuclear physics and astrophysics *** upcoming High-energy FRagment Separator(HFRS)at the High-Intensity heavy-ion Accelerator Facility(HIAF),an in-flight separator at relativistic energies,is characterized by high beam intensity,large ion-optical acceptance,high magnetic rigidity,and high momentum resolution *** provides an opportunity to study the production and properties of neutron-rich nuclei around N=*** this paper,an experimental scheme is proposed to produce neutron-rich nuclei around N=126 and simultaneously measure their mass and lifetime based on the HFRS separator;the feasibility of this scheme is evaluated through *** results show that under the high-resolution optical mode,many new neutron-rich nuclei approaching the r-process abundance peak around A=195 can be produced for the first time,and many nuclei with unknown masses and lifetimes can be produced with high *** the time-of-flight corrected by the measured dispersive position and energy loss information,the cocktails produced from 208 Pb fragmentation can be unambiguously ***,the masses of some neutron-rich nuclei near N=126 can be measured with high precision using the time-of-flight magnetic rigidity *** indicates that the HIAF-HFRS facility has the potential for the production and property research of neutron-rich nuclei around N=126,which is of great significance for expanding the chart of nuclides,developing nuclear theories,and understanding the origin of heavy elements in the universe.

关键词： HFRS Fragmentation Neutron-rich nuclei around N=126 Mass measurement Lifetime

General radical difluoromethylation using difluoroacetic anhydride via photoredox catalysis

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Science China Chemistry 2024年第8期67卷 2637-2646页

作者： Meng He Yankai Yang heng Zhang zhipeng Guan zhi-Bing Dong Hong Yi Aiwen Lei School of Chemistry and Environmental Engineering Wuhan Institute of TechnologyWuhan 430205China College of Chemistry and Molecular Sciences and Institute for Advanced Studies(IAS) Wuhan UniversityWuhan 430072China

CF_(2)H-containing molecules play pivotal roles in diverse fields from medicinal chemistry to materials science. However, the application of existing CF_(2)H reagents as a source of CF_(2)H radical is limited by their reactivity and preparation. Herein, we develop a simple and general visible-light-catalyzed radical difluoromethylation reaction of alkenes, dienes, and heteroaromatics using commercially available, easy-to-handle, and low-cost difluoroacetic anhydride as the CF_(2)H reagent. This scalable protocol enables the convenient synthesis of a range of CF_(2)H-containing compounds under mild conditions, exhibiting a broad substrate scope and functional group tolerance. Potential applications are further demonstrated by gram-scale synthesis, sunlight experiments, derivatization experiments as well as the synthesis of bioactive molecules.

关键词： radical difluoromethylation alkenes/dienes/heteroaromatics difluoroacetic anhydride photoredox

Delayed-measurement one-way quantum computing on cloud quantum computer

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Chinese Physics B 2024年第9期33卷 125-131页

作者： zhi-Peng Yang Yu-Ran Zhang Fu-Li Li heng Fan Beijing Academy of Quantum Information Science Beijing 100193China Ministry of Education Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Quantum Information and Quantum Optoelectronic DevicesSchool of PhysicsXi’an Jiaotong UniversityXi’anShaanxi 710049China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China Institute of Physics China Academy of SciencesBeijing 100190China

One-way quantum computation focuses on initially generating an entangled cluster state followed by a sequence of measurements with classical communication of their individual ***,a delayed-measurement approach has been applied to replace classical communication of individual measurement *** this work,by considering the delayed-measurement approach,we demonstrate a modified one-way CNOT gate using the on-cloud superconducting quantum computing platform:*** modified protocol for one-way quantum computing requires only three qubits rather than the four used in the standard *** this modified cluster state decreases the number of physical qubits required to implement one-way computation,both the scalability and complexity of the computing process are *** to previous work,this modified one-way CNOT gate is superior to the standard one in both fidelity and resource *** have also numerically compared the behavior of standard and modified methods in large-scale one-way quantum *** results suggest that in a noisy intermediate-scale quantum(NISQ)era,the modified method shows a significant advantage for one-way quantum computation.

关键词： measurement-based quantum computing quantum entanglement quantum gates

Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang xie zhi-Liang Qin Jian-Hua Wang Peng Song heng-Guang Shen Sheng-Qi Yu Ben-Jun Ma xue-Qin Liu Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component

Amorphous Sb/C composite with isotropic expansion property as an ultra-stable and high-rate anode for lithium-ion batteries

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Rare Metals 2024年第5期43卷 2039-2052页

作者： Ze-Zhou Yang Cheng-Yi Zhang Yu-Qing Ou zhi-Kang Su Yan Zhao heng-Jiang Cong xin-Ping Ai Jiang-Feng Qian Hubei Key Laboratory of Electrochemical Power Sources College of Chemistry and Molecular SciencesWuhan UniversityWuhan430072China Institute of Technological Sciences Wuhan UniversityWuhan 430072China

Antimony(Sb)is an intriguing anode material for Li-ion batteries(LIBs)owing to its high theoretical capacity of 660 m Ah·g^(-1)and appropriate working potential of~0.8 V(***^(+)/Li).However,just like all alloying materials,the Sb anode suffers from huge volume expansion(230%)during repeated insertion/extraction of Li+ions,resulting in structural deterioration and rapid capacity *** this work,a novel amorphous Sb/C composite with atomically dispersed Sb particles in carbon matrix is prepared via a straightforward high-energy ball milling *** intimate intermixing of amorphous Sb with C provides homogeneous element distribution and isotropic volume expansion during cycling,resulting in persistent structural ***,the disordered structure of amorphous material shortens the diffusion distance of lithium ions/electrons,promoting fast reaction kinetics and rate *** from the aforementioned effects,the amorphous Sb/C exhibits a high reversible capacity of537.4 m Ah·g^(-1)at 0.1 A·g^(-1)and retains 201.0 m Ah·g^(-1)at an ultrahigh current rate of 10.0 A·g^(-1).Even after 1500deep cycles at 2.0 A·g^(-1),the amorphous Sb/C electrode still maintains 86.3%of its initial capacity,which outperforms all existing Sb-based anodes reported so *** analysis further reveals a greatly reduced volume variation of merely 34.6%for the amorphous Sb/C electrode,much lower than that of 223.1%for crystalline Sb *** study presents a new approach to stabilizing Sb-based alloy anodes and contributes to the construction of high-performance amorphous anode materials for LIBs,enabling advanced energy storage.

关键词： Amorphous Sb/C anode Homogeneous element distribution Isotropic volume expansion Ultra-long cycle stability High-rate capability Lithium-ion battery

Dehydration-triggered structural phase transition-associated ferroelectricity in a hybrid perovskite-type crystal

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Chinese Chemical Letters 2024年第10期35卷 487-490页

作者： zhi-Yuan Yue Hua-Kai Li Na Wang Shan-Shan Liu Le-Ping Miao heng-Yun Ye Chao Shi Chaotic Matter Science Research Center Jiangxi University of Science and Technology

Since the appearance of Rochelle salt, ferroelectrics have received extensive attention from researchers due to they are playing an important role in sensors, memories, mechanical actuation, and so on. In recent years, with the rapid development of molecular ferroelectrics, high-performance molecular ferroelectrics have become effective complement to inorganic ferroelectrics. However, compared with inorganic ferroelectrics, the family of molecular ferroelectrics is relatively scarce, and exploring highperformance ferroelectric materials through new synthesis strategies has become the trend of molecular ferroelectrics. Here, we successfully transformed non-polar material 1（2-H2PCA）2（H2O）CdCl6（2-H2PCA = 2-picolylamine cation） into polar material 2（2-H2PCA）2CdCl6by single-crystal to single-crystal transformation（SCSCT）. Meanwhile, 2 exhibits clear ferroelectricity with a high-temperature Tcof 378 K,a Psof 1.18 μC/cm2at 300 K. This work not only realizes the purpose of synthesizing ferroelectrics by forming polar structures by SCSCT, but also realizes the reversibility of SCSCT, which provides ideas for the construction and exploration of new molecular ferroelectrics.

关键词： Ferroelectric materials Hybrid perovskite Phase transition Single-crystal to single-crystal transformation Stimulus-structure-response

Elimination of cracks in stainless steel casings via 3D printed sand molds with an internal topology structure

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China Foundry 2024年第4期21卷 319-326页

作者： Jun-hang xu Bao-zhi Li Zhao-wei Song Yun-bao Gao Jing-ming Li Yu Wang Qiu-lin Wen heng Cao Zeng-rui Wang National Key Laboratory of Advanced Casting Technologies Shenyang 110022China Shenyang Research Institute of Foundry Co. Ltd.CAMShenyang 110022China

The important supporting component in a gas turbine is the casing,which has the characteristics of large size,complex structure,and thin *** the context of existing 3DP sand casting processes,casting crack defects are prone to *** leads to an increase in the scrap rate of casings,causing significant resource ***,the presence of cracks poses a significant safety hazard after the casings are put into *** generation of different types of crack defects in stainless steel casings is closely related to casting stress and the high-temperature concession of the sand ***,the types and causes of cracks in stainless steel casing products,based on their structural characteristics,were systematically *** sand molds with different internal topology designs were printed using the 3DP technology to investigate the impact of sand mold structures on high-temperature *** optimal sand mold structure was used to cast casings,and the crack suppression effect was verified by analyzing its eddy current testing *** experimental results indicate that the skeleton structure has an excellent effect on suppressing cracks in the *** research holds important theoretical and engineering significance in improving the quality of casing castings and reducing production costs.

关键词： gas turbine casing crack defects 3D printed sand mold topological structure high-temperature concession

Highly uniform Co-Cu bimetallic sulfides for rechargeable alkaline aqueous zinc batteries

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Chinese Chemical Letters 2024年第2期35卷 521-526页

作者： xiaofang Bai Yuwei Zhao Mangwei Cui Tianshuo Guo Zijie Tang Chuan Li heng Gao Shuo Yang Lingzhi Zhao Chunyi zhi Hongfei Li Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Songshan Lake Materials Laboratory Dongguan 523808China Department of Materials Science and Engineering City University of Hong KongHong KongChina International Centre for Quantum and Molecular Structures Department of PhysicsShanghai UniversityShanghai 200444China Guangdong Provincial Engineering Technology Research Center for Low Carbon and Advanced Energy Materials Institute of Semiconductor Science and TechnologySouth China Normal UniversityGuangzhou 510631China

Rechargeable alkaline aqueous zinc batteries(RAZBs)have attracted increasing ***,most RAZBs are hindered by the limited availability of cathode *** practical electrochemical performance of most cathode materials is lower than the theoretical value due to their poor electrical conductivity and low utilization *** this work,we develop a facile hydrothermal procedure to prepare highly uniform bimetallic sulfides as novel cathode materials for ***-cobalt binary metallic oxides materials possess higher conductivity and larger capacity compared with their mono-metal oxides compounds due to bimetallic synergistic effects and multiple oxidation ***,bimetallic sulfide compounds have smaller bond energy and longer bond length than their oxides,leading to less structural damage,faster kinetics of electrochemical reactions,and better *** as-prepared Co-Cu bimetallic sulfides show enhanced electrochemical performance due to various valences of Co and Cu as well as the existence of *** a result,aqueous Zn/CuCo_(2)S_(4) battery shows a high specific capacity of 117.4 mAh/g at 4 A/g and a good cycle life of over 8000 *** on PANa hydrogel electrolytes,a flexible Zn/CuCo_(2)S_(4) battery demonstrates excellent cycling *** battery can also meet the requirements of electronic devices with different shapes and performs well in extreme environments,such as freezing,drilling,and *** work opens new avenues to obtain high-rate and long-life cathode materials for RAZBs by utilizing the synergistic effects of bimetallic sulfides and provides a new platform for flexible energy storage devices.

关键词： Aqueous zinc batteries Bimetallic sulfides Cathode materials Rate performance Cycling stability

Ultrafast pulse-dilation framing camera and its application for time-resolved x-ray diagnostic

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Nuclear Science and Techniques 2024年第7期35卷 101-114页

作者： Hou-zhi Cai Qiu-Yan Luo Kai-xuan Lin xuan Deng Jun-Kai Liu Kai-zhi Yang Dong Wang Jia-Jie Chen Jia-heng Wang Jing-Hua Long Li-Hong Niu Yun-Fei Lei Jin-Yuan Liu Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province Shenzhen Key Laboratory of Photonics and BiophotonicsCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China

An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were *** camera achieved a temporal resolution of 10 ps by using a pulse-dilation device and gated MCP imager,and a spatial resolution of 100μm by using an electronic imaging system comprising combined magnetic *** spatial resolution characteristics of the camera were studied both theoretically and *** results showed that the camera with combined magnetic lenses reduced the field curvature and acquired a larger working area.A working area with a diameter of 53 mm was created by applying four magnetic lenses to the ***,the camera was used to detect the x-rays produced by the laser-targeting *** diagnostic results indicated that the width of the x-ray pulse was approximately 18 ps.

关键词： Inertial confinement fusion Plasma diagnostics Framing camera Combined lenses Pulse-dilation