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Possibilities for the synthesis of superheavy element Z=121 in fusion reactions

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Nuclear Science and Techniques 2024年第6期35卷 90-100页

作者： Ming-Hao zhang Yu-Hai zhang ying Zou xiu-xiu Yang Gen zhang Feng-Shou zhang The Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physical Science and Technology Guangxi UniversityNanning 530004China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Based on the dinuclear system model,the calculated evaporation residue cross sections matched well with the current experimental *** synthesis of superheavy elements Z=121 was systematically studied through combinations of stable projectiles with Z=21-30 and targets with half-lives exceeding 50 *** influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in *** reactions^(254)Es(^(46)Ti,3n)^(297)121 and^(252)Es(^(46)Ti,3n)^(295)121 were found to be experimentally feasible for synthesizing superheavy element Z=121,with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV,respectively.

关键词： Superheavy nuclei Dinuclear system model Fusion reaction Evaporation residue cross section

Energy Efficiency Maximization in Mobile Edge Computing Networks via IRS assisted UAV Communications

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1865-1884页

作者： ying zhang Weiming Niu Supu xiu Guangchen Mu School of Electronic Information Engineering Henan Institute of TechnologyXinxiang453003China Houde College Henan Institute of TechnologyXinxiang453003China Department of Science Henan Institute of TechnologyXinxiang453003China

In this paper,we investigate the energy efficiency maximization for mobile edge computing(MEC)in intelligent reflecting surface(IRS)assisted unmanned aerial vehicle(UAV)*** particular,UAVcan collect the computing tasks of the terrestrial users and transmit the results back to them after *** jointly optimize the users’transmitted beamforming and uploading ratios,the phase shift matrix of IRS,and the UAV trajectory to improve the energy *** formulated optimization problem is highly non-convex and difficult to be solved ***,we decompose the original problem into three *** first propose the successive convex approximation(SCA)based method to design the beamforming of the users and the phase shift matrix of IRS,and apply the Lagrange dual method to obtain a closed-form expression of the uploading *** the trajectory optimization,we propose a block coordinate descent(BCD)based method to obtain a local optimal ***,we propose the alternating optimization(AO)based overall algorithmand analyzed its complexity to be equivalent or lower than existing *** results show the superiority of the proposedmethod compared with existing schemes in energy efficiency.

关键词： Mobile edge computing(MEC) unmanned aerial vehicle(UAV) intelligent reflecting surface(IRS) energy efficiency

Classification of knowledge graph completeness measurement techniques

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Journal of Systems Engineering and Electronics 2024年第1期35卷 154-162页

作者： zhang ying XIAO Gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and *** assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same ***,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge *** them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among *** this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness *** purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.

关键词： quality assessment completeness assessment closed world assumptions open world assumption partial completeness assumption

A bifunctional POM-based Cu-viologen complex with mixed octamolybdate clusters for rapid oxidation desulfurization and effective photogeneration of hydrogen

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Rare Metals 2024年第1期43卷 236-246页

作者： Lin Yang Zhong zhang Chao-Nan zhang xiu-Li Wang College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Professional Technology Innovation Center of Liaoning Province for Conversion Materials of Solar Cell Bohai UniversityJinzhou 121013China

The design and synthesis of catalysts for the oxidation desulfurization and production of hydrogen are extremely important for solving environmental pollution and energy ***,a novel bifunctional [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)-based Cu-viologen complex H_(4)[Cu_(2)~ⅠCl_(2)(Hbcbpy)_(4)] [α-Mo_(8)O_(26)] [β-Mo8O_(26)]·H_(2)O(BHU-2,Hbcbpy=1-(4-carboxybenzyl)-4,4'-bipyridinium) was synthesized and characterized by single-crystal X-ray diffraction(XRD),infrared radiation spectra,powder X-ray diffraction(PXRD) and X-ray photoelectron spectroscopy(XPS) *** structural characteristic of BHU-2 is the presence of two types of octamolybdate clusters [α-Mo_(8)O_(26)]^(4-)/[β-Mo_(8)O_(26)]^(4-)and a new binuclear Cu~Ⅰ-Hbcbpy complex linked by Cl-bridges[Cu_(2)ⅠCl_(2)(Hbcbpy)_(4)]^(4+).BHU-2 as a heterogeneous catalyst exhibits excellent activities to the oxidation desulfurization and photocatalytic hydrogen *** room temperature,BHU-2 can catalyze 96% conversion of methyl phenyl sulfide with 98% selectivity,and the process obeys the pseudo-first-order reaction kinetic with the half-life of9.6 *** notorious 2-chloroethyl ethyl sulfide can achieve 99% conversion with 98% selectivity within only1 min at the presence of BHU-2,and the turnover frequency(TOF) is up to 7400 h^(-1).BHU-2 also exhibits high catalytic activity for the oxidation of other aromatic and aliphatic thioethers within short time at room ***,BHU-2 shows a high catalytic activity for visible-light-driven hydrogen evolution with an H_(2) evolution rate of 1677.85 μmol·g^(-1)·h^(-1) within 10 ***,the catalytic activities do not decrease evidently after three cycles,revealing the prominent structural stability and recyclability.

关键词： Polyoxometalate Metal-organic complex Viologen Oxidation desulfurization Photocatalytic hydrogen production

Optimizing FeCoNiCrTi high-entropy alloy with hydrogen pumping effect to boost de/hydrogenation performance of magnesium hydride

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Rare Metals 2024年第7期43卷 3273-3285页

作者： Meng-Chen Song Fu-ying Wu Yi-Qun Jiang xiu-Zhen Wang Hu Zhao Li-Xin Chen Liu-Ting zhang School of Energy and Power Instrumental Analysis CenterJiangsu University of Science and TechnologyZhenjiang 212003China Max Planck Institute for Iron Research 40237DuisseldorfGermany School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

The exploration of efficient,long-lived and cost-effective transition metal catalysts is highly desirable for the practical hydrogen storage of magnesium hydride(MgH_(2)) in sustainable energy ***,FeCoNiCrTi high-entropy alloy(HEA) nanosheets were prepared via a facile wet chemical ball milling strategy and they were introduced into MgH_(2) to boost the hydrogen storage *** refined HEA exhibited superior catalytic activity on MgH_(2).In contrast to additive-free MgH_(2),the initial desorption temperature of the constructed MgH_(2)-HEA composite was reduced from 330.0 to 198.5℃ and a remarkable 51% reduction in the dehydrogenation activation energy was ***,the MgH_(2)-HEA composite only required one-twentieth time of that consumed by pure MgH_(2) to absorb 5.0 wt% of H_(2) at 225℃.The synergy between the "hydrogen pumping" effect of Mg_2Ni/Mg_2NiH_4 and Mg_2Co/Mg_2CoH_5 couples,as well as the good dispersion of Fe,Cr and Ti on the surface of MgH_(2) contributed to the enhanced de/hydrogenation performance of the MgH_(2)-HEA *** study furnishes important steering for the design and fabrication of multiple transition metal catalysts and may push the commercial application of magnesium-based hydrides one step forward.

关键词： Hydrogen storage Magnesium hydride High-entropy alloys Catalysis

Deep Guided Attention Network for Joint Denoising and Demosaicing in Real Image

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Chinese Journal of Electronics 2024年第1期33卷 303-312页

作者： Tao zhang ying FU Jun zhang School of Computer Science and Technology Beijing Institute of Technology Advanced Reasearch Institute of Multidisciplinary Science Beijing Institute of Technology

Denoising(DN) and demosaicing(DM) are the first crucial stages in the image signal processing pipeline. Recently, researches pay more attention to solve DN and DM in a joint manner, which is an extremely undetermined inverse problem. Existing deep learning methods learn the desired prior on synthetic dataset, which limits the generalization of learned network to the real world data. Moreover, existing methods mainly focus on the raw data property of high green information sampling rate for DM, but occasionally exploit the high intensity and signalto-noise(SNR) of green channel. In this work, a deep guided attention network(DGAN) is presented for real image joint DN and DM(JDD), which considers both high SNR and high sampling rate of green information for DN and DM, respectively. To ease the training and fully exploit the data property of green channel, we first train DN and DM sub-networks sequentially and then learn them jointly, which can alleviate the error accumulation. Besides, in order to support the real image JDD, we collect paired raw clean RGB and noisy mosaic images to conduct a realistic dataset. The experimental results on real JDD dataset show the presented approach performs better than the state-of-the-art methods, in terms of both quantitative metrics and qualitative visualization.

关键词： Training Visualization Inverse problems Green products Noise reduction Pipelines Signal processing

Two missense STK11 gene variations impaired LKB1/adenosine monophosphate-activated protein kinase signaling in Peutz-Jeghers syndrome

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1532-1546页

作者： Jin Liu Si-Cong Zeng An Wang Hai-ying Cheng Qian-Jun zhang Guang-xiu Lu Hunan Guangxiu Hospital Hunan Normal UniversityChangsha 410000Hunan ProvinceChina Scientific Research Department Reproductive and Genetic Hospital of Citic-XiangyaChangsha 410000Hunan ProvinceChina

BACKGROUND Peutz-Jeghers syndrome(PJS)is a rare hereditary neoplastic disorder mainly associated with serine/threonine kinase 11(STK11/LKB1)gene *** genetic testing can protect a patient’s offspring from mutated genes;however,some variations in this gene have been interpreted as variants of uncertain significance(VUS),which complicate reproductive decision-making in genetic *** To identify the pathogenicity of two missense variants and provide clinical *** Whole exome gene sequencing and Sanger sequencing were performed on the peripheral blood of patients with PJS treated at the Reproductive and Genetic Hospital of *** was employed to predict the protein structure,conservation,and pathogenicity of the two missense variation sites in patients with ***,plasmids were constructed and transfected into HeLa cells to observe cell *** differences in signal pathway expression between the variant group and the wild-type group were compared using western blot and *** analysis was performed using one-way analysis of variance.PG(***297Gly)and c.733C>T(***245Phe)]in 9 unrelated PJS families who were seeking reproductive *** two missense VUS were located in the catalytic domain of serine/threonine kinase,which is a key structure of the liver kinase B1(LKB1)*** vitro experiments showed that the phosphorylation levels of adenosine monophosphate-activated protein kinase(AMPK)at Thr172 and LKB1 at Ser428 were significantly higher in transfected variation-type cells than in wild-type *** addition,the two missense STK11 variants promoted the proliferation of HeLa *** immunohistochemical analysis showed that phosphorylated-AMPK(Thr172)expression was significantly lower in gastric,colonic,and uterine polyps from PJS patients with misse

关键词： Missense STK11 Peutz-Jeghers syndrome Rare disease Genetic counseling Assisted reproductive technique

Role of 5-azacytidine in differentiation of human mesenchymal stem cell sinto cardiomyocytes in vitro

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Journal of Geriatric Cardiology 2009年第3期6卷 182-188页

作者： Fang-Ge Deng Yu-Lin Li xiu-ying zhang Key Laboratory of Pathobiology Jilin University Changchun 130021 China National Key Laboratory of Respiratory Diseases Guangzhou Institute of Respiratory Diseases First Affiliated Hospital of Guangzhou Medical College Guangzhou 510120 China

Objective 5-azacytidine could induce the differentiation of stem cells into cardiomyocytes （CMs）. The aim of this study was to screen the optimal condition for 5-azacytidine inducing differentiation of human mesenchumal stem cells （hMSCs） into CMs, and the effect of 5-azacytidine on adherence, cell vigor and chromosome karyotype of hMSCs. Methods hMSCs were isolated from human bone marrow and cultured in vitro. The phenotypes ofhMSCs were identified by flow cytometric analyses. MTT test was used to investigate the effect of different concentrations of 5-azacytidine on proliferation ofhMSCs. Four weeks after 5-azacytidine induction, semi-quantitative RT-PCR, transmission electron microscopy （TEM）, single-cell action potentials, detection of cardio-enzyme AST and LDH, cell adherence, cell viability and chromosome karyotype test were performed. Results The typical morphological features of hMSCs were fibroblast-like in shape, hMSCs expressed CD44 and CD105,and did not express CD34, CD45 and CD31. The optimal concentration of 5-azacytidine was 10μ mol/L. The shape of hMSCs treated with 5-Azacytidine changed from fusiform to polygon or astrocyte gradually, and passaged cells were evenly arranged as polarity structure. Indueed-hMSCs connected with neighbouring cells, fbrming myotube-like structures 4 weeks later. It was confirmed that induced hMSCs shaped myotubule-like structure and had some of micro-histologic structures of CMs by TEM. RT-PCR showed that induced hMSCs expressed cardiac specific product BNNP and early cardio-myogenesis specific transcription factor NKX2.5mRNA. Besides, induced-MSCs led to the weak action potential and secreted cardio-enzyme AST and LDH. There was no significant difference in cell adherence and viability before and after induction. Both hMSCs and induced-hNSCs kept stable normal diploid nucleus. Conclusion The optimal condition for inducing effect of 5-azacytidine is 10 la mol/L and 24-hour incubation; and under this condition, the adhere

关键词： Human mesenchymal stem cells 5-azacytidine differentiation cardiomyocytes

A Detailed Thermal Resistance Network Analysis of FCBGA Package

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Journal of Thermal Science 2024年第1期33卷 18-28页

作者： DANG Hao LU Yang DU Yanzheng zhang xiu zhang Qian MA Weigang zhang Xing Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Zhongxing Telecom Equipment Corporation Shanghai 201203China

Using thermal models to describe the heat dissipation process of FCBGA is a significant topic in the field of ***,the thermal resistance model considering the structure of each part of the chip is still ambiguous and rare,but it is quite desirable in *** this work,we propose a detailed thermal resistance network model,and describe it by using thermal conduction resistance and thermal spreading *** a striking FCBGA case,we calculated the thermal resistance of each part of the structure according to the temperature field simulated by *** thermal resistance network can be used to predict the temperatures in the chip under different *** example,when the power changes by 40%,the relative error of junction temperature prediction is only 0.24%.The function of the detailed thermal resistance network in evaluating the optimization space and determining the optimization direction is *** work illustrates a potential thermal resistance analysis method for electronic devices such as FCBGA.

关键词： FCBGA package thermal resistance network thermal spreading resistance junction temperature