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Advances in Manufacturing 2024年第2期12卷 288-299页

作者： Zhao-Qing Zhang Kai-Ning Shi yao-yao Shi Yi-Hui song Zhe He ya-song pu School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072People’s Republic of China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine(Northwestern Polytechnical University) Ministry of EducationXi’an710072People’s Republic of China

Profile grinding is the most crucial method for the ultra-precision machining of special-shaped ***,profile grinding produces a unique machining profile,and many random factors in the machining process lead to complex surface *** this study,the structural and probabilistic characteristics of the profile grinding of a special-shaped surface were analyzed,and a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding was *** forming process of a GH738 blade tenon tooth surface was considered as an example to demonstrate the *** comparison results showed that the simulation results had similar surface characteristics to the measurement results,and the relative error range of the 3D roughness parameter was 0.21%–19.76%,indicating an accurate prediction and characterization of the complex special-shaped surface under the action of multiple factors.

关键词： Special-shaped surface Profile grinding Surface morphology 3D characterization

Engineering FeOOH/Ni(OH)_(2) heterostructures on Ni_(3)S_(2)surface to enhance seawater splitting

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Rare Metals 2024年第5期43卷 1989-1998页

作者： Chen yang ya-Dong Li Li-Juan Cao Xi-Long Wang Han-pu Liang Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Sino-Danish College University of Chinese Academy of SciencesBeijing 100049China

The construction of highly stable and efficient electrocatalysts is desirable for seawater splitting but remains challenging due to the high concentration of Cl-in ***,FeOOH/Ni(OH)_(2)heterostructure supported on Ni_(3)S_(2)-covered nickel foam(Fe–Ni/Ni_(3)S_(2)/NF)was fabricated by hydrothermal and etching methods,as well as anodic oxidation *** electronic structure of FeOOH and Ni(OH)_(2)could be modulated after depositing FeOOH nanoparticles on Ni(OH)_(2)nanosheet,which greatly boosted the catalytic *** the catalyst used as an electrode for oxygen evolution reaction(OER),it needed low overpotentials of 266 and 368 m V to achieve current densities of 100 and 800 m A·cm^(-2),respectively,in 1 mol·L^(-1)KOH+seawater *** can operate continuously at 100 m A·cm^(-2)for 400 h without obvious ***,in situ generated SO_(4)^(2-)from inner Ni_(3)S_(2)during electrolysis process would accumulate on the surface of active sites to form passivation layers to repel Cl^(-),which seemed to be responsible for superior *** study not only synthesizes an OER catalyst for highly selective and stable seawater splitting,but also gives a novel approach for industrial hydrogen production.

关键词： Anodic oxidation Heterostructure Oxygen evolution reaction Seawater splitting

Crocus genome reveals the evolutionary origin of crocin biosynthesis

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1878-1891页

作者： Zhichao Xu Shanshan Chen yalin Wang ya Tian Xiaotong Wang Tianyi Xin Zishan Li Xin Hua Shengnan Tan Wei Sun Xiangdong pu Hui yao Ranran Gao Jingyuan song Key Lab of Chinese Medicine Resources Conservation State Administration of Traditional Chinese Medicine of the People's Republic of ChinaInstitute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China State Key Laboratory of Basis and New Drug Development of Natural and Nuclear Drugs Engineering Research Center of Chinese Medicine ResourceMinistry of EducationBeijing 100193China College of Life Science Northeast Forestry UniversityHarbin 150040China Key Laboratory of Beijing for Identification and Safety Evaluation of Chinese Medicine China Academy of Chinese Medical SciencesInstitute of Chinese Materia MedicaBeijing 100700China Analysis and Testing Center of Northeast Forestry University Harbin 150040China School of Pharmacy Anhui Medical UniversityInflammation and Immune Mediated Diseases Laboratory of Anhui ProvinceHefei 230032China

Crocus sativus (saffron) is a globally autumn-flowering plant, and its stigmas are the most expensive spice and valuable herb medicine. Crocus specialized metabolites, crocins, are biosynthesized in distant species, Gardenia (eudicot) and Crocus (monocot), and the evolution of crocin biosynthesis remains poorly understood. With the chromosome-level Crocus genome assembly, we revealed that two rounds of lineage-specific whole genome triplication occurred, contributing important roles in the production of carotenoids and apocarotenoids. According to the kingdom-wide identification, phylogenetic analysis, and functional assays of carotenoid cleavage dioxygenases (CCDs), we deduced that the duplication, site positive selection, and neofunctionalization of Crocus-specific CCD2 from CCD1 members are responsible for the crocin biosynthesis. In addition, site mutation of CsCCD2 revealed the key amino acids, including I143, L146, R161, E181, T259, and S292 related to the catalytic activity of zeaxanthin cleavage. Our study provides important insights into the origin and evolution of plant specialized metabolites, which are derived by duplication events of biosynthetic genes.

关键词： Crocus sativus WGT Crocin biosynthesis Carotenoids Apocarotenoids CCDs

Access to advanced sodium-ion batteries by presodiation:Principles and applications

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Journal of Energy Chemistry 2024年第5期92卷 162-175页

作者： Shihao Zhang Ruoyu Cao Xiangjun pu Along Zhao Weihua Chen Chunhua song Yongjin Fang Yuliang Cao College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072HubeiChina College of Chemistry&Green Catalysis Center Zhengzhou UniversityZhengzhou 450001HenanChina Shenzhen Janaenergy techonulogy Co. Ltd.Shenzhen 518000GuangdongChina School of Chemistry and Chemical Engineering Jiangsu University of TechnologyChangzhou 213001JiangsuChina Zonergy Corporation NO.68 Fucang RoadYantan DistrictZigong 643030SichuanChina

Sodium-ion batteries(SIBs)are expected to offer affordability and high energy density for large-scale energy storage ***,the commercial application of SIBs is hurdled by low initial coulombic efficiency(ICE),continuous Na loss during long-term operation,and low sodium-content of cathode *** this scenario,presodiation strategy by introducing an external sodium reservoir has been rationally proposed,which could supplement additional sodium ions into the system and thereby markedly improve both the cycling performance and energy density of *** this review,the significance of presodiation is initially introduced,followed by comprehensive interpretation on technological properties,underlying principles,and associated approaches,as well as our perspectives on present inferiorities and future research ***,this contribution outlines a distinct pathway towards the presodiation methodology,of significance but still in its nascent phase,which may inspire the targeted guidelines to explore new chemistry in this field.

关键词： Presodiation Increased coulombic efficiency High reversible capacity Sodium ion batteries

Using an improved lightweight YOLOv8 model for real-time detection of multi-stage apple fruit in complex orchard environments

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ARTIFICIAL INTELLIGENCE IN AGRICULTURE 2024年第1期11卷 70-82页

作者： Ma, Baoling Hua, Zhixin Wen, Yuchen Deng, Hongxing Zhao, Yongjie pu, Liuru song, Huaibo Northwest A&F Univ Coll Mech & Elect Engn Yangling 712100 Shaanxi Peoples R China Minist Agr & Rural Affairs Key Lab Agr Internet Things Yangling 712100 Shaanxi Peoples R China Shaanxi Key Lab Agr Informat Percept & Intelligent Yangling 712100 Shaanxi Peoples R China

For the purpose of monitoring apple fruits effectively throughout the entire growth period in smart orchards. A lightweight model named YOLOv8n-ShuffleNetv2-Ghost-SE was proposed. The ShuffleNetv2 basic modules and down-sampling modules were alternately connected, replacing the Backbone of YOLOv8n model. The Ghost modules replaced the Conv modules and the C2fGhost modules replaced the C2f modules in the Neck part of the YOLOv8n. ShuffleNetv2 reduced the memory access cost through channel splitting operations. The Ghost module combined linear and non-linear convolutions to reduce the network computation cost. The Wise-IoU (WIoU) replaced the CIoU for calculating the bounding box regression loss, which dynamically adjusted the anchor box quality threshold and gradient gain allocation strategy, optimizing the size and position of predicted bounding boxes. The Squeeze-and-Excitation (SE) was embedded in the Backbone and Neck part of YOLOv8n to enhance the representation ability of feature maps. The algorithm ensured high precision while having small model size and fast detection speed, which facilitated model migration and deployment. Using 9652 images validated the effectiveness of the model. The YOLOv8n-ShuffleNetv2-Ghost-SE model achieved Precision of 94.1%, Recall of 82.6%, mean Average Precision of 91.4%, model size of 2.6 MB, parameters of 1.18 M, FLOPs of 3.9 G, and detection speed of 39.37 fps. The detection speeds on the Jetson Xavier NX development board were 3.17 fps. Comparisons with advanced models including Faster R-CNN, SSD, YOLOv5s, YOLOv7-tiny, YOLOv8s, YOLOv8n, MobileNetv3_small-Faster, MobileNetv3_small-Ghost, ShuflleNetv2-Faster, ShuflleNetv2-Ghost, ShuflleNetv2-Ghost-CBAM, ShuflleNetv2-Ghost-ECA, and ShuflleNetv2-Ghost-CA demonstrated that the method achieved smaller model and faster detection speed. The research can provide reference for the development of smart devices in apple orchards. (c) 2024 The Authors. publishing services by Elsevier B.V. o

关键词： Multi-stage apple fruit Deep learning Real-time detection Lightweight model MACHINE

A possible probe to neutron-skin thickness by fragment parallel momentum distribution in projectile fragmentation reactions

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Nuclear Science and Techniques 2024年第6期35卷 114-119页

作者： Chun-Wang Ma Yi-Jie Duan ya-Fei Guo Chun-Yuan Qiao Yu-Ting Wang Jie pu Kai-Xuan Cheng Hui-Ling Wei College of Physics Henan Normal UniversityXinxiang 453007China Institute of Nuclear Science and Technology Henan Academy of SciencesZhengzhou 450015China

Neutron-skin thickness is a key parameter for a neutron-rich nucleus;however,it is difficult to *** the framework of the Lanzhou Quantum Molecular Dynamics(LQMD)model,a possible probe for the neutron-skin thickness(δ_(np))of neutron-rich ^(48)Ca was studied in the 140A MeV ^(48)Ca+^(9)Be projectile fragmentation reaction based on the parallel momentum distribution(p∥)of the residual fragments.A Fermi-type density distribution was employed to initiate the neutron density distributions in the LQMD simulations.A combined Gaussian function with different width parameters for the left side(Γ_(L))and the right side(Γ_(R))in the distribution was used to describe the p∥of the residual *** neutron-rich sulfur isotopes as examples,Γ_(L) shows a sensitive correlation withδ_(np) of ^(48)Ca,and is proposed as a probe for determining the neutron skin thickness of the projectile nucleus.

关键词： Neutron-skin thickness Projectile fragmentation Parallel momentum distribution Neutron-rich nucleus Quantum molecular dynamics model

Extending the solid solution range of sodium ferric pyrophosphate:Off‐stoichiometric Na_(3)Fe(2.5)(P_(2)O_(7))_(2)as a novel cathode for sodium‐ion batteries

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Carbon Energy 2024年第4期6卷 128-139页

作者： Xiang jun pu Kunran yang Zibing Pan Chunhua song yangyang Lai Renjie Li Zheng‐Long Xu Zhongxue Chen Yuliang Cao Hubei Key Laboratory of Electrochemical Power Sources College of Chemistry and Molecular SciencesWuhan UniversityWuhanChina Key Laboratory of Hydraulic Machinery Transients Ministry of EducationSchool of Power and Mechanical EngineeringWuhan UniversityWuhanChina School of Chemistry and Chemical Engineering Jiangsu University of TechnologyChangzhouJiangsuChina Zonergy Corporation ZigongSichuanChina Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHung HomHong Kong SARChina

Iron‐based pyrophosphates are attractive cathodes for sodium‐ion batteries due to their large framework,cost‐effectiveness,and high energy ***,the understanding of the crystal structure is scarce and only a limited candidates have been reported so *** this work,we found for the first time that a continuous solid solution,Na_(4−α)Fe_(2+α)_(2)(P_(2)O_(7))_(2)(0≤α≤1,could be obtained by mutual substitution of cations at center‐symmetric Na3 and Na4 sites while keeping the crystal building blocks of anionic P_(2)O_(7) *** particular,a novel off‐stoichiometric Na_(3)Fe(2.5)(P_(2)O_(7))_(2)is thus proposed,and its structure,energy storage mechanism,and electrochemical performance are extensively investigated to unveil the structure–function *** as‐prepared off‐stoichiometric electrode delivers appealing performance with a reversible discharge capacity of 83 mAh g^(−1),a working voltage of 2.9 V(***^(+)/Na),the retention of 89.2%of the initial capacity after 500 cycles,and enhanced rate capability of 51 mAh g^(−1)at a current density of 1600 mA g^(−1).This research shows that sodium ferric pyrophosphate could form extended solid solution composition and promising phase is concealed in the range of Na_(4−α)Fe_(2+α)_(2)(P_(2)O_(7))_(2),offering more chances for exploration of new cathode materials for the construction of high‐performance SIBs.

关键词： extending solid‐solution range off‐stoichiometric Na_(3)Fe_(2.5)(P_(2)O_(7))_(2) sodium‐ion batteries structure-function relationship

Bi-Frobenius Algebra Structures on Quantum Complete Intersections

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1481-1504页

作者： Hai JIN pu ZHANG School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240P.R.China

This paper is to look for bi-Frobenius algebra structures on quantum complete intersections over field *** find a class of comultiplications,such that if√−1∈k,then a quantum complete intersection becomes a bi-Frobenius algebra with comultiplication of this form if and only if all the parameters qij=±***,it is proved that if√−1∈k then a quantum exterior algebra in two variables admits a bi-Frobenius algebra structure if and only if the parameter q=±√*** if−1/∈k,then the exterior algebra with two variables admits no bi-Frobenius algebra *** prove that the quantum complete intersections admit a bialgebra structure if and only if it admits a Hopf algebra structure,if and only if it is commutative,the characteristic of k is a prime p,and every ai a power of *** also provides a large class of examples of bi-Frobenius algebras which are not bialgebras(and hence not Hopf algebras).In commutative case,other two comultiplications on complete intersection rings are given,such that they admit non-isomorphic bi-Frobenius algebra structures.

关键词： Bi-Frobenius algebras coalgebras bialgebras Hopf algebras quantum complete intersections quantum exterior algebras

Efficacyand Safetyof Huashi Baidu Granules in Treating Patients with SARS-CoV-2Omicron Variant: A Single-Center Retrospective Cohort Study

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Chinese Journal of Integrative Medicine 2024年第2期30卷 107-114页

作者： CHEN Cai-yu ZHANG Wen XU Xiang-ru pu Yu-ting TU ya-dan PENG Wei yaO Xuan ZHOU Shuang FANG Bang-jiang Department of Emergency Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai(200032)China Department of Classical Traditional Chinese Medicine Chongqing Hospital of Traditional Chinese MedicineChongqing(400021)China Acupuncture and Massage College Shanghai University of Traditional Chinese MedicineShanghai(201203)China Institute of Emergency and Critical Care Medicine Shanghai University of Traditional Chinese MedicineShanghai(200032)China

Objective:To evaluate the efficacy and safety of Huashi Baidu Granules(HSBD)in treating patients with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron ***:A single-center retrospective cohort study was conducted during COVID-19 Omicron epidemic in the Mobile Cabin Hospital of Shanghai New International Expo Center from April 1st to May 23rd,*** COVID-19 patients with asymptomatic or mild infection were assigned to the treatment group(HSBD users)and the control group(non-HSBD users).After propensity score matching in a 1:1 ratio,496 HSBD users of treatment group were matched by propensity score to 496 non-HSBD *** in the treatment group were administrated HSBD(5 g/bag)orally for 1 bag twice a day for 7 consecutive *** in the control group received standard care and routine *** primary outcomes were the negative conversion time of nucleic acid and negative conversion rate at day *** outcomes included the hospitalized days,the time of the first nucleic acid negative conversion,and new-onset symptoms in asymptomatic *** events(AEs)that occurred during the study were *** subgroup analysis was conducted in vaccinated(378 HSBD users and 390 non-HSBD users)and unvaccinated patients(118 HSBD users and 106 non-HSBD users).Results:The median negative conversion time of nucleic acid in the treatment group was significantly shortened than the control group[3 days(IQR:2-5 days)vs.5 days(IQR:4-6 days);P<0.01].The negative conversion rate of nucleic acid in the treatment group were significantly higher than those in the control group at day 7(91.73%vs.86.90%,P=0.014).Compared with the control group,the hospitalized days in the treatment group were significantly reduced[10 days(IQR:8-11 days)vs.11 days(IQR:10.25-12 days);P<0.01].The time of the first nucleic acid negative conversion had significant differences between the treatment and control groups[3 days(IQR:2-4 days)vs.5 days(IQR:

关键词： Huashi Baidu Granule severe acute respiratory syndrome coronavirus 2 Omicron variant retrospective cohort trial Chinese medicine

High-static-low-dynamic stiffness isolator based on an electromagnetic negative stiffness spring with long linear stroke

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Science China(Technological Sciences) 2024年第3期67卷 740-752页

作者： YUAN ShuJin WU yaJun song DaiPing pu Huayan MOU LiSheng HOU Lei ZHAO JingLei LI XuePing LUO Jun WU Jie HUANG XiaoXu State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China China Aerodynamics Research and Development Center Mianyang 621000China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

Negative stiffness mechanisms can improve low-frequency vibration isolation performance and have been widely used in the vibration isolation of precision equipment. However, the negative stiffness mechanism usually introduces a nonlinear stiffness,resulting in a nonlinear response and worsening the vibration isolation performance, especially under large amplitude *** this paper, an electromagnetic spring with linear negative stiffness(ESLNS) is proposed, in which the antagonistic ampere forces of the energized coils are used to generate negative stiffness within a long linear stroke. The magnetic field distribution is improved through the design of the magnetic circuit, thereby increasing the stiffness generation efficiency. The stiffness can be adjusted bidirectionally by current within the range of positive and negative stiffness. An electromagnetic stiffness model was established based on the equivalent magnetic circuit method. Experimental measurements verified the accuracy of the model and proved the linearity of the electromagnetic spring. A vibration isolator with high static and low dynamic stiffness(HSLDS) based on the ESLNS is designed and tested. The experimental results prove that the introduction of the ESLNS can effectively expand the isolation frequency band without changing the equilibrium position. Moreover, the vibration isolator with ESLNS does not produce nonlinear response. The proposed electromagnetic spring with linear negative stiffness extends the application range of HSLDS isolators to a large amplitude vibration environment.

关键词： linear negative stiffness mechanism low-frequency vibration isolation electromagnetic spring vibration control