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Small-signal Stability Constrained Optimal Power Flow Considering Eigenvalue Distribution

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1052-1062页

作者： Zheng Huang Kewen Wang Yi Wang jing han Jun Liang the School of Electrical and Information Engineering Zhengzhou UniversityZhengzhou 450001China Cardiff University Cardiff CF243AAU.K.

In the existing small-signal stability constrained op-timal power flow(SSSC-OPF)algorithms,only the rightmost ei-genvalue or eigenvalues that do not satisfy a given threshold,e.g.,damping ratio threshold and real-part threshold of eigen-value,are considered in the small-signal stability *** effect of steady-state,i.e.,operating point,changes on eigen-values is not fully taken into *** this paper,the small-signal stability constraint that can fully reflect the eigenvalue change and system dynamic performance requirement is formed by analyzing the eigenvalue distribution on the complex *** small-signal stability constraint is embedded into the standard optimal power flow model for generation *** simultaneous solution formula of the SSSC-OPF is es-tablished and solved by the quasi-Newton approach,while pen-alty factors corresponding to the eigenvalue constraints are de-termined by the stabilization degree of constrained *** improve the computation speed,a hybrid algorithm for ei-genvalue computation in the optimization process is proposed,which includes variable selection for eigenvalue estimation and strategy selection for eigenvalue *** effectiveness of the proposed algorithm is tested and validated on the New England 10-machine 39-bus system and a modified practical 68-machine 2395-bus system.

关键词： Damping ratio eigenvalue optimal power flow quasi-Newton approach sensitivity small-signal stability

Feasibility of medical radioisotope production based on the proton beams at China Spallation Neutron Source

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Nuclear Science and Techniques 2024年第6期35卷 26-39页

作者： Bing Jiang Bin-Bin Tian han-Tao jing Qi-Fan Dong Spallation Neutron Source Science Center Dongguan 523803China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The utilization of a proton beam from the China Spallation Neutron Source(CSNS)for producing medical radioisotopes is appealing owing to its high current intensity and high *** medical isotope production based on the proton beam at the CSNS is significant for the development of future radiopharmaceuticals,particularly for theα-emitting *** production yield and activity of typical medical isotopes were estimated using the FLUKA *** results indicate that the 300-MeV proton beam with a power of 100 kW at CSNS-II is highly suitable for proof-of-principle studies of most medical *** particular,this proton beam offers tremendous advantages for the large-scale production of alpha radioisotopes,such as 225Ac,whose theoretical production yield can reach approximately 57 Ci/*** on these results,we provide perspectives on the use of CSNS proton beams to produce radioisotopes for medical applications.

关键词： CSNS proton beam Medical isotope production α-Emitting radionuclides Nuclidic purity analysis

Role of 5-hydroxytryptamine type 3 receptors in the regulation of anxiety reactions

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第1期25卷 23-37页

作者： Yinan DU Zhiwei LI Yukui ZHAO jing han Weiping HU Zhiqiang LIU MOE Key Laboratory of Modern Teaching Technology Shaanxi Normal UniversityXi’an710062China

5-Hydroxytryptamine(5-HT)type 3 receptor(5-HT_(3)R)is the only type of ligand-gated ion channel in the 5-HT receptor *** the high permeability of Na+,K+,and Ca2+and activation of subsequent voltage-gated calcium channels(VGCCs),5-HT_(3)R induces a rapid increase of neuronal excitability or the release of neurotransmitters from axon terminals in the central nervous system(CNS).5-HT_(3)Rs are widely expressed in the medial prefrontal cortex(mPFC),amygdala(AMYG),hippocampus(HIP),periaqueductal gray(PAG),and other brain regions closely associated with anxiety *** have a bidirectional regulatory effect on anxiety reactions by acting on different types of cells in different brain regions.5-HT_(3)Rs mediate the activation of the cholecystokinin(CCK)system in the AMYG,and theγ-aminobutyric acid(GABA)“disinhibition”mechanism in the prelimbic area of the mPFC promotes anxiety by the activation of GABAergic intermediate inhibitory neurons(IINs).In contrast,a 5-HT_(3)R-induced GABA“disinhibition”mechanism in the infralimbic area of the mPFC and the ventral HIP produces anxiolytic effects.5-HT_(2)R-mediated regulation of anxiety reactions are also activated by 5-HT_(3)R-activated 5-HT release in the HIP and *** provides a theoretical basis for the treatment of anxiety disorders or the production of anxiolytic drugs by targeting 5-HT_(3)***,given the circuit specific modulation of 5-HT_(3)Rs on emotion,systemic use of 5-HT_(3)R agonism or antagonism alone seems unlikely to remedy anxiety,which deeply hinders the current clinical application of 5-HT_(3)R ***,the exploitation of circuit targeting methods or a combined drug strategy might be a useful developmental approach in the future.

关键词： 5-Hydroxytryptamine type 3 receptor(5-HT_(3)R) Anxiety Medial prefrontal cortex Amygdala Hippocampus Periaqueductal gray

Mechanical and damping performances of TPMS lattice metamaterials fabricated by laser powder bed fusion

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China Foundry 2024年第4期21卷 327-333页

作者： Yan-peng Wei Huai-qian Li jing-jing han Ying-chun Ma Hao-ran Zhou jing-chang Cheng Jian Shi Zhi-quan Miao Bo Yu Feng Lin National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China

Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ***,its vibration and noise reduction,and damping properties have not been fully ***,in this study,the TPMS structures with parameterization were designed by the method of surface migration,and the TPMS structures with high forming quality was manufactured by laser powder bed fusion(LPBF).The mechanical properties and energy absorption characteristics of the beam and TPMS structures were studied and compared by quasi-static *** modal shapes of the beam lattice structures and TPMS structures were obtained by the free modal analysis,and the damping properties of two structures were obtained by modal *** the two structures after heat treatment with the same porosity of 70%,the yield strength of the beam lattice structure reaches 40.76 MPa,elastic modulus is 20.38 GPa,the energy absorption value is 32.23 MJ·m^(-3),the damping ratio is 0.52%.The yield strength,elastic modulus,energy absorption value,and damping ratio of the TPMS structure are 50.74 MPa,25.37 GPa,47.34 MJ·m^(-3),and 0.99%,*** results show that TPMS structures exhibit more excellent mechanical properties and energy absorption,better damping performance,and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity.

关键词： lattice metamaterials TPMS energy absorption damping laser powder bed fusion

Comparisons and optimization of two absorption chiller types by considering heat transfer area, exergy and economy as single-objective functions

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CLEAN ENERGY 2024年第1期8卷 55-65页

作者： Qiu, Yida Wang, jingkun han, jing Chen, Yuzhu Wang, Jun Lund, Peter D. Univ Liverpool Management Sch Liverpool L693BX Lancs England Power China Huadong Engn Corp Ltd 201 Gaojiao Rd Hangzhou 311122 Peoples R China Southeast Univ Key Lab Solar Energy Sci & Technol Jiangsu Prov 2 Si Pai Lou Nanjing 210096 Peoples R China Aalto Univ Sch Sci POB 15100 FI-00076 Espoo Finland

Absorption cooling technology is an environmentally friendly method to generate continuous chilled water making use of multiple thermal sources, such as waste heat and renewable thermal energy. In this study, two absorption chillers (nominal capacity of 400 kW) with series and parallel connections are evaluated. To research the ideal configuration of chillers after thermodynamic analysis, the structures of the chillers are optimized using the particle swarm optimization algorithm by considering the heat transfer area (HTA), exergy efficiency and total annual cost as single-objective functions. The impact of temperature differences between external and internal flows, heat exchanger efficiencies and the solution allocation ratio is estimated. The optimized HTA, coefficient of performance, exergy efficiency and total annual cost are 149.0 m2, 1.56, 29.44% and $229 119 for the series-connected chiller, and 146.7 m2, 1.59, 31.45% and $234 562 for the parallel-connected type, respectively. Under the lowest HTA condition, compared with the reference simulation results, the energy and exergy performances are improved, while the annual total cost is higher. The annual total cost is highest when maximizing the exergy efficiency, which is attributed to the increase in the HTA. The operating cost accounts for 27.42% (series type) and 26.54% (parallel type) when the annual cost is the lowest. Two absorption chillers with series and parallel connections are evaluated using a thermodynamic analysis. The chiller structures are optimized using the particle swarm optimization algorithm by considering the heat transfer area, exergy efficiency and total annual cost as single-objective functions. Graphical Abstract

关键词： absorption chiller series/parallel-connected temperature difference parameters solution allocation ratio REFRIGERATION SYSTEMS COOLING SYSTEM MULTIOBJECTIVE OPTIMIZATION PERFORMANCE ANALYSIS CLIMATE ZONES SERIES PARALLEL ENERGY CONSUMPTION REDUCE

Construction of a predictive model for gastric cancer neuroaggression and clinical validation analysis: A single-center retrospective study

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2602-2611页

作者： Yu-Yin Lan jing han Yan-Yan Liu Lei Lan Department of Stomatology Shanghai Municipal Hospital of Traditional Chinese MedicineShanghai University of Traditional Chinese MedicineShanghai 200071China Department of Biobank Zhejiang Cancer HospitalHangzhou 310005Zhejiang ProvinceChina Department of General Surgery Peking University First HospitalBeijing 100034China Department of Oncology Zhejiang HospitalHangzhou 310013Zhejiang ProvinceChina

BACKGROUND This study investigated the construction and clinical validation of a predictive model for neuroaggression in patients with gastric *** cancer is one of the most common malignant tumors in the world,and neuroinvasion is the key factor affecting the prognosis of ***,there is a lack of systematic analysis on the construction and clinical application of its prediction *** study adopted a single-center retrospective study method,collected a large amo-unt of clinical data,and applied statistics and machine learning technology to build and verify an effective prediction model for neuroaggression,with a view to providing scientific basis for clinical treatment decisions and improving the tr-eatment effect and survival rate of patients with gastric *** To investigate the value of a model based on clinical data,spectral computed to-mography(CT)parameters and image omics characteristics for the preoperative prediction of nerve invasion in patients with gastric *** A retrospective analysis was performed on 80 gastric cancer patients who under-went preoperative energy spectrum CT at our hospital between January 2022 and August 2023,these patients were divided into a positive group and a negative group according to their pathological *** data were collected,the energy spectrum parameters of primary gastric cancer lesions were measured,and single factor analysis was performed.A total of 214 image omics features were extracted from two-phase mixed energy images,and the features were screened by single factor analysis and a support vector *** variables with statist-ically significant differences were included in logistic regression analysis to construct a prediction model,and the performance of the model was evaluated using the subject working characteristic *** were statistically significant differences in sex,carbohydrate antigen 199 expression,tumor thickness,Lauren classification

关键词： Gastric neoplasms Nerve invasion Tomography X-ray computer Imaging omics Diagnostic differentiation

Aβ-Carotene Ketolase Gene NfcrtO from Subaerial Cyanobacteria Confers Drought Tolerance in Rice

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Rice science 2024年第1期31卷 62-76页

作者： GAO Ningning YE Shuifeng ZhanG Yu ZHOU Liguo MA Xiaosong YU hanxi LI Tianfei han jing LIU Zaochang LUO Lijun College of Plant Science and Technology Huazhong Agricultural UniversityWuhan 430070China Shanghai Agrobiological Gene Center Shanghai 201106China College of Life Sciences Shangrao Normal UniversityShangrao 334001China Institute for Agri-food Standards and Testing Technology Shanghai Academy of Agricultural SciencesShanghai 201403China

Nostoc flagelliforme is a terrestrial cyanobacterium that can resist many types of stressors,including drought,ultraviolet radiation,and extreme *** this study,we identified the drought tolerance gene NfcrtO,which encodes aβ-carotene ketolase,through screening the transcriptome of *** under water loss *** expression of NfcrtO under 0.6 mol/L sorbitol or under 0.3 mol/L NaCl stress significantly increased the growth rate of Escherichia *** NfcrtO was heterologously expressed in rice,the seedling height and root length of NfcrtO-overexpressing rice plants were significantly higher than those of the wild type(WT)plants grown on½Murashige and Skoog solid medium with 120 mmol/L mannitol at the seedling *** analysis revealed that NfcrtO was involved in osmotic stress,antioxidant,and other stress-related ***,the survival rate of the NfcrtO-overexpression lines was significantly higher than that of the WT line under both hydroponic stress(24%PEG and 100 mmol/L H_(2)O_(2))and soil drought treatment at the seedling *** traits,including the activity levels of superoxide dismutase,peroxidase,catalase,total antioxidant capacity,and the contents of proline,trehalose,and soluble sugar,were significantly improved in the NfcrtO-overexpression lines relative to those in the WT line under 20%PEG ***,when water was withheld at the booting stage,the grain yield per plant of NfcrtO-overexpression lines was significantly higher than that of the WT *** two-hybrid analysis identified interactions between NfcrtO and Dna J protein,E3 ubiquitin-protein ligase,and pyrophosphate-energized vacuolar membrane proton ***,heterologous expression of NfcrtO in rice could significantly improve the tolerance of rice to osmotic stress,potentially facilitating the development of new rice varieties.

关键词： antioxidant enzyme β-carotene ketolase drought resistance Nostoc flagelliforme osmotic stress rice transcriptome analysis

Knowledge,Attitude,and Practice Towards Mpox and Associated Factors Among HIV-Infected Individuals—Beijing Municipality,China,2023

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China CDC weekly 2024年第7期6卷 109-117,I0001,I0002页

作者： Yue Gu Ruiqi Ren jing han Wenqing Bai Yuanyuan Zhang Haoliang Liu Zhaohe Li Chao Li Rui Song Lei Zhou Chinese Center for Disease Control and Prevention BeijingChina National Center for Infectious Diseases Beijing Ditan HospitalCapital Medical UniversityBeijingChina Beijing Key Laboratory of Emerging Infectious Diseases Institute of Infectious DiseasesBeijing Ditan HospitalCapital Medical UniversityBeijingChina Nanjing Medical University Nanjing CityJiangsu ProvinceChina

Summary What is already known about this topic?Approximately 50%of patients with mpox are human immunodeficiency virus(HIV)-infected *** have shown that individuals with advanced HIV infection tend to have more severe... 详细信息

关键词： mortality Infect clinical

Theoretical Exploration of Alloying Effects on Stabilities and Mechanical Properties ofγʹPhase in Novel Co–Al–Nb-Base Superalloys

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1238-1248页

作者： Guan-Cheng Gu Zhao-jing han Ze-Yu Chen Zhao-Xuan Li Sheng-Bao Xia Zheng-Ning Li Hua Jin Wei-Wei Xu Xing-Jun Liu Shenzhen Research Institute of Xiamen University School of Aerospace EngineeringXiamen UniversityXiamen361005China Institute of Materials Genome and Big Data Harbin Institute of TechnologyShenzhen518055China

The new developedγ/γʹCo–Al–Nb-base alloys show great potentials as high-temperature ***,finding appropriate compositions to improve performance of alloys still poses a great challenge to the development of Co–Al–Nb-base *** by the lack of alloying effects on fundamental properties of criticalγʹphase,we systematically performed a theoretical investigation on the effect of alloying elements TM(TM:Ti,V,Cr,Zr,Mo,Ta,W,Re,and Ru)on phase stabilities and mechanical properties of L1_(2)-typeγʹ(Co,Ni)_(3)(Al,Nb).By analyzing the stability ofγʹphase with respect to its competitive B2 and D0_(19) phases,the results shown that Ti,V,and Cr enhance the L1_(2) stability and widen the L1_(2)–D0_(19) energy barrier,in which V yields the maximum *** analysis of electronic structure indicated that the alternation of valence electrons at fermi level would be the atomic origin for doping TM inγʹ*** calculated results of mechanical properties shown that V and Cr are expected to be optimal dopant for enhancing the strength and the ductility ofγʹ*** addition of Ta is also beneficial for enhancing the strength at the slight expense of ductility ofγʹ*** drawing the mechanical maps,the preferred composition range for the phases with desired properties is roughly demarcated in theory for the multi-addition of V/Cr and V/Ta inγʹ*** findings would be useful for optimizing the performance of novelγ/γʹCo–Al–Nb-base superalloys.

关键词： Co-Al-Nb-base superalloys γ/γʹdual-phase Phase stability Mechanical properties First-principle methods