期刊文献+
共找到526篇文章
< 1 2 27 >
每页显示 20 50 100
制造发展的三个范式:制造发展规律的研究 被引量:3
1
作者 房丰洲 赖敏 +11 位作者 王金石 吕鹏 于楠 罗熙淳 胡春光 陈远流 陈磊 邓辉 徐涛 康城玮 韩伟 冯俊元 《中国科学基金》 CSSCI CSCD 北大核心 2024年第1期159-171,共13页
基于对人类社会发展历史和科学技术发展内在规律的认识,本文详细分析了制造发展的三个范式,论证了原子及近原子尺度制造是制造范式III的核心使能技术。文章回顾了国内外各机构对原子级制造研发规划现状,指出我国目前处于原子级制造技术... 基于对人类社会发展历史和科学技术发展内在规律的认识,本文详细分析了制造发展的三个范式,论证了原子及近原子尺度制造是制造范式III的核心使能技术。文章回顾了国内外各机构对原子级制造研发规划现状,指出我国目前处于原子级制造技术发展的重要战略机遇期,并从设计、材料、加工和检测等角度分析了原子级制造的技术体系内涵;梳理了原子级表面制造、原子级结构制造、原子级测量与表征等领域的研究进展,呈现了当前具有原子级制造能力的部分代表性技术,包括原子级切削、原子级抛光、电化学加工、等离子体原子级加工技术、原子精准操控以及原子分辨测量与表征技术,并对原子级制造战略规划提出发展建议。 展开更多
关键词 制造技术发展趋势 制造范式 原子及近原子尺度制造 原子精度制造 原子级制造
原文传递
原子级制造的关键基础科学问题
2
作者 雒建斌 郭东明 +17 位作者 杨华勇 叶鑫 钱林茂 居冰峰 姜澜 邵金友 张振宇 陈磊 陈远流 胡洁 李祥明 冯俊元 韩伟娜 谭新峰 解国新 赖一楠 苗鸿雁 王岐东 《中国科学基金》 CSSCI CSCD 北大核心 2024年第1期86-98,共13页
人类的制造技术逐步向原子级推进,原子作为化学反应中的最小粒子,虽然它可以分成更小的原子核、电子等,但是从制造的角度看,原子级制造可以说是人类制造的最底层技术,也是继微纳制造之后新的制造范式,可将制造精度以及产品性能推向极致... 人类的制造技术逐步向原子级推进,原子作为化学反应中的最小粒子,虽然它可以分成更小的原子核、电子等,但是从制造的角度看,原子级制造可以说是人类制造的最底层技术,也是继微纳制造之后新的制造范式,可将制造精度以及产品性能推向极致水平,代表着人类对物质世界认知和制造能力发展的新阶段,是引领未来产业变革发展的战略性技术,也是保障国家安全和推动国计民生重大装备跨代升级的重要前沿方向。本文基于第330期双清论坛总结了原子级制造的研究现状、发展趋势及机遇挑战,凝练出未来5~10年原子级制造的焦点问题和亟需解决的关键科学问题,探讨了相关领域的前沿发展方向和科学基金资助战略。 展开更多
关键词 原子级制造 原子层制造 团簇与器件制造 原子级精度制造 原子级测量与表征 学科交叉
原文传递
润滑耐磨耐蚀功能一体化有机黏结涂层的研究进展
3
作者 陈明锴 陈磊 +3 位作者 马彦军 张定军 周惠娣 陈建敏 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第4期182-190,共9页
随着现代化装备技术的快速发展,高端机械装备服役工况变得愈加复杂苛刻,磨损与腐蚀耦合损伤加速了高端机械装备运动部件的损伤失效,导致装备服役寿命大幅缩减,带来了严重的安全问题。润滑耐磨耐蚀功能一体化有机黏结涂层克服了润滑耐磨... 随着现代化装备技术的快速发展,高端机械装备服役工况变得愈加复杂苛刻,磨损与腐蚀耦合损伤加速了高端机械装备运动部件的损伤失效,导致装备服役寿命大幅缩减,带来了严重的安全问题。润滑耐磨耐蚀功能一体化有机黏结涂层克服了润滑耐磨涂层和防腐蚀涂层的单一功能局限,为解决运动部件的磨损和腐蚀问题提供了有效方案。文中首先探讨了关键运动部件面临复杂服役工况的严峻挑战、材料磨损与腐蚀耦合的损伤机制;然后分别由黏结剂、填料和润滑剂3个方面介绍了目前润滑耐磨耐蚀功能一体化有机黏结涂层的研究进展,对涂层的组成结构与力学性能、摩擦学性能、耐腐蚀性能间的构效关系进行了分析,并对不同涂层的局限性进行了概述;之后详细总结了润滑耐磨耐蚀功能一体化涂层的应用现状;最后对润滑耐磨耐蚀功能一体化涂层的发展方向进行展望。 展开更多
关键词 磨损-腐蚀 减摩耐磨 耐蚀 功能一体化 有机黏结涂层
下载PDF
Engineering g-C_(3)N_(4)based materials for advanced photocatalysis:Recent advances 被引量:1
4
作者 Xin-Lian Song lei chen +2 位作者 Li-Jiao Gao Jin-Tao Ren Zhong-Yong Yuan 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期166-197,共32页
Photocatalysis driven by abundant yet intermittent solar energy has considerable potential in renewable energy generation and environmental remediation.The outstanding electronic structure and physicochemical properti... Photocatalysis driven by abundant yet intermittent solar energy has considerable potential in renewable energy generation and environmental remediation.The outstanding electronic structure and physicochemical properties of graphitic carbon nitride(g-C_(3)N_(4)),together with unique metal-free characteristic,make them ideal candidates for advanced photocatalysts construction.This review summarizes the up-to-date advances on g-C_(3)N_(4)based photocatalysts from ingenious-design strategies and diversified photocatalytic applications.Notably,the advantages,fabrication methods and limitations of each design strategy are systemically analyzed.In order to deeply comprehend the inner connection of theory–structure–performance upon g-C_(3)N_(4)based photocatalysts,structure/composition designs,corresponding photocatalytic activities and reaction mechanisms are jointly discussed,associated with introducing their photocatalytic applications toward water splitting,carbon dioxide/nitrogen reduction and pollutants degradation,etc.Finally,the current challenges and future perspectives for g-C_(3)N_(4)based materials for photocatalysis are briefly proposed.These design strategies and limitations are also instructive for constructing g-C_(3)N_(4) based materials in other energy and environment-related applications. 展开更多
关键词 Graphitic carbon nitride g-C_(3)N_(4) Design strategies PHOTOCATALYSIS PHOTOCATALYSTS Reaction mechanism
下载PDF
Synergetic optimization operation method for distribution network based on SOP and PV 被引量:1
5
作者 lei chen Ning Zhang +4 位作者 Xingfang Yang Wei Pei Zhenxing Zhao Yinan Zhu Hao Xiao 《Global Energy Interconnection》 EI CSCD 2024年第2期130-141,共12页
The integration of distributed generation brings in new challenges for the operation of distribution networks,including out-of-limit voltage and power flow control.Soft open points(SOP)are new power electronic devices... The integration of distributed generation brings in new challenges for the operation of distribution networks,including out-of-limit voltage and power flow control.Soft open points(SOP)are new power electronic devices that can flexibly control active and reactive power flows.With the exception of active power output,photovoltaic(PV)devices can provide reactive power compensation through an inverter.Thus,a synergetic optimization operation method for SOP and PV in a distribution network is proposed.A synergetic optimization model was developed.The voltage deviation,network loss,and ratio of photovoltaic abandonment were selected as the objective functions.The PV model was improved by considering the three reactive power output modes of the PV inverter.Both the load fluctuation and loss of the SOP were considered.Three multi-objective optimization algorithms were used,and a compromise optimal solution was calculated.Case studies were conducted using an IEEE 33-node system.The simulation results indicated that the SOP and PVs complemented each other in terms of active power transmission and reactive power compensation.Synergetic optimization improves power control capability and flexibility,providing better power quality and PV consumption rate. 展开更多
关键词 Synergetic optimization Soft open point(SOP) Photovoltaic(PV) Distribution network
下载PDF
右美托咪定对脊柱手术患者术中血流动力学和失血量的影响:系统回顾和荟萃分析
6
作者 汪玫 车建翔 +2 位作者 陈磊 宋婷婷 瞿金涛 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第1期54-68,I0006,共16页
目的 右美托咪定是一种高选择性的α2肾上腺素能受体激动剂,具有降低血压和心率的作用。本研究旨在探讨右美托咪定对脊柱手术患者术中血流动力学和失血量的影响。方法 检索Web of Science、MEDLINE、EMBASE和Cochrane图书馆截至2023年2... 目的 右美托咪定是一种高选择性的α2肾上腺素能受体激动剂,具有降低血压和心率的作用。本研究旨在探讨右美托咪定对脊柱手术患者术中血流动力学和失血量的影响。方法 检索Web of Science、MEDLINE、EMBASE和Cochrane图书馆截至2023年2月发表的随机对照研究,比较右美托咪定和生理盐水对脊柱手术术中血流动力学和失血量的影响。根据研究间的异质性采用固定或随机效应模型。结果 纳入21项随机对照研究,共1388例患者。右美托咪定的使用增加了术中低血压(OR:2.11;95%CI:1.24-3.58;P=0.006)和心动过缓(OR:2.48;95%CI:1.57-3.93;P=0.0001)的总体风险。特别是在给予负荷剂量时,低血压(OR:2.00;95%CI:1.06-3.79;P=0.03)和心动过缓(OR:2.28;95%CI:1.42-3.66;P=0.0007)的风险更为显著。当右美托咪定与静脉麻醉联合使用时,患者更容易出现血流动力学不稳定的情况,包括低血压(OR:2.90;95%CI:1.24-6.82;P=0.01)和心动过缓(OR:2.66;95%CI:1.53-4.61;P=0.0005)。与吸入麻醉联合时,仅增加了心动过缓的风险(OR:4.95;95%CI:1.41-17.37;P=0.01)。然而,当与静吸复合麻醉联合使用时,并未增加低血压和心动过缓的风险。此外,右美托咪定还增加了重度低血压的风险(OR:2.57;95%CI:1.05-6.32;P=0.04),但对轻度低血压的影响并不显著。对于心动过缓而言,无论是轻度(OR:2.55;95%CJ:1.06-6.15;P=0.04)还是重度(OR:2.45;95%CI:1.43-4.20;P=0.001)的风险都有所增加。总体而言,右美托咪定对术中失血量的影响并不显著,但在与吸入麻醉联合时,失血量显著减少(MD:-82.97;95%CI:-109.04--56.90;P<0.001)。结论 右美托咪定在脊柱手术过程中增加了低血压和心动过缓的风险。给予负荷剂量或与不同麻醉维持方式联合使用可能会对术中血流动力学和失血量产生不同的影响。然而,目前的研究结果仍需进一步证实和探讨。 展开更多
关键词 右美托咪定 术中血流动力学 失血量 脊柱手术
下载PDF
Nomogram predicting the prognosis of primary liver cancer after radiofrequency ablation combined with transcatheter arterial chemoembolization 被引量:1
7
作者 Hai-Hua Shen Yu-Rong Hong +4 位作者 Wen Xu lei chen Jun-Min chen Zhi-Gen Yang Cai-Hong chen 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2630-2639,共10页
BACKGROUND The incidence and mortality rates of primary hepatocellular carcinoma(HCC)are high,and the conventional treatment is radiofrequency ablation(RFA)with transcatheter arterial chemoembolization(TACE);however,t... BACKGROUND The incidence and mortality rates of primary hepatocellular carcinoma(HCC)are high,and the conventional treatment is radiofrequency ablation(RFA)with transcatheter arterial chemoembolization(TACE);however,the 3-year survival rate is still low.Further,there are no visual methods to effectively predict their prognosis.AIM To explore the factors influencing the prognosis of HCC after RFA and TACE and develop a nomogram prediction model.METHODS Clinical and follow-up information of 150 patients with HCC treated using RFA and TACE in the Hangzhou Linping Hospital of Traditional Chinese Medicine from May 2020 to December 2022 was retrospectively collected and recorded.We examined their prognostic factors using multivariate logistic regression and created a nomogram prognosis prediction model using the R software(version 4.1.2).Internal verification was performed using the bootstrapping technique.The prognostic efficacy of the nomogram prediction model was evaluated using the concordance index(CI),calibration curve,and receiver operating characteristic RESULTS Of the 150 patients treated with RFA and TACE,92(61.33%)developed recurrence and metastasis.Logistic regression analysis identified six variables,and a predictive model was created.The internal validation results of the model showed a CI of 0.882.The correction curve trend of the prognosis prediction model was always near the diagonal,and the mean absolute error before and after internal validation was 0.021.The area under the curve of the prediction model after internal verification was 0.882[95%confidence interval(95%CI):0.820-0.945],with a specificity of 0.828 and sensitivity of 0.656.According to the Hosmer-Lemeshow test,χ^(2)=3.552 and P=0.895.The predictive model demonstrated a satisfactory calibration,and the decision curve analysis demonstrated its clinical applicability.CONCLUSION The prognosis of patients with HCC after RFA and TACE is affected by several factors.The developed prediction model based on the influencing parameters shows a good prognosis predictive efficacy. 展开更多
关键词 NOMOGRAM Primary liver cancer Radiofrequency ablation Transcatheter arterial chemoembolization PROGNOSIS Influencing factors Decision curve analysis
下载PDF
运用ISO 37111逐步提升城市社区可持续发展水平——以咸宁赤壁市为例
8
作者 雷晨 陈琼 +1 位作者 王文君 杨锋 《中国标准化》 2024年第21期152-156,共5页
随着全球化和城市化进程的加速,城市地区面临着日益严峻的可持续发展挑战。ISO 37111:2024作为一项新的国际标准,旨在为城市区域、城镇、县和社区提供一套灵活的实施指南,以促进ISO 37101标准的逐步和有效实施。标准提出了九种灵活方法... 随着全球化和城市化进程的加速,城市地区面临着日益严峻的可持续发展挑战。ISO 37111:2024作为一项新的国际标准,旨在为城市区域、城镇、县和社区提供一套灵活的实施指南,以促进ISO 37101标准的逐步和有效实施。标准提出了九种灵活方法,允许城市定居点根据自身条件选择适合自己的发展目标,这些方法包括建立共享愿景、确定路线图和里程碑、组织研讨会、准备就绪评估、能力评审、特定规划、政策和激励措施的制定、关键绩效指标(KPI)框架的建立以及行动计划的实施。湖北咸宁赤壁市运用ISO 37111《城市和社区可持续发展-城市社区-ISO 37101分阶段灵活性实施指南》国际标准提供的方法,在羊楼洞古镇的新型城镇化工作中开展可持续发展实践,验证国际标准中方法是否适用,探索中小型城市可持续发展路径。 展开更多
关键词 赤壁羊楼洞 标准验证 可持续发展
下载PDF
Near-zero-adhesion-enabled intact wafer-scale resist-transfer printing for high-fidelity nanofabrication on arbitrary substrates
9
作者 Zhiwen Shu Bo Feng +5 位作者 Peng Liu lei chen Huikang Liang Yiqin chen Jianwu Yu Huigao Duan 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期313-326,共14页
There is an urgent need for novel processes that can integrate different functional nanostructures onto specific substrates,so as to meet the fast-growing need for broad applications in nanoelectronics,nanophotonics,a... There is an urgent need for novel processes that can integrate different functional nanostructures onto specific substrates,so as to meet the fast-growing need for broad applications in nanoelectronics,nanophotonics,and fexible optoelectronics.Existing direct-lithography methods are difficult to use on fexible,nonplanar,and biocompatible surfaces.Therefore,this fabrication is usually accomplished by nanotransfer printing.However,large-scale integration of multiscale nanostructures with unconventional substrates remains challenging because fabrication yields and quality are often limited by the resolution,uniformity,adhesivity,and integrity of the nanostructures formed by direct transfer.Here,we proposed a resist-based transfer strategy enabled by near-zero adhesion,which was achieved by molecular modification to attain a critical surface energy interval.This approach enabled the intact transfer of wafer-scale,ultrathin-resist nanofilms onto arbitrary substrates with mitigated cracking and wrinkling,thereby facilitating the in situ fabrication of nanostructures for functional devices.Applying this approach,fabrication of three-dimensional-stacked multilayer structures with enhanced functionalities,nanoplasmonic structures with~10 nm resolution,and MoS2-based devices with excellent performance was demonstrated on specific substrates.These results collectively demonstrated the high stability,reliability,and throughput of our strategy for optical and electronic device applications. 展开更多
关键词 resist-based transfer printing near-zero adhesion critical surface energy wafer-scale nanofabrication in situ fabrication optoelectronic devices
下载PDF
Scheduling optimization for UAV communication coverage using virtual force-based PSO model
10
作者 Jianguo Sun Wenshan Wang +2 位作者 Sizhao Li Qingan Da lei chen 《Digital Communications and Networks》 SCIE CSCD 2024年第4期1103-1112,共10页
When the ground communication base stations in the target area are severely destroyed,the deployment of Unmanned Aerial Vehicle(UAV)ad hoc networks can provide people with temporary communication services.Therefore,it... When the ground communication base stations in the target area are severely destroyed,the deployment of Unmanned Aerial Vehicle(UAV)ad hoc networks can provide people with temporary communication services.Therefore,it is necessary to design a multi-UAVs cooperative control strategy to achieve better communication coverage and lower energy consumption.In this paper,we propose a multi-UAVs coverage model based on Adaptive Virtual Force-directed Particle Swarm Optimization(AVF-PSO)strategy.In particular,we first introduce the gravity model into the traditional Particle Swarm Optimization(PSO)algorithm so as to increase the probability of full coverage.Then,the energy consumption is included in the calculation of the fitness function so that maximum coverage and energy consumption can be balanced.Finally,in order to reduce the communication interference between UAVs,we design an adaptive lift control strategy based on the repulsion model to reduce the repeated coverage of multi-UAVs.Experimental results show that the proposed coverage strategy based on gravity model outperforms the existing state-of-the-art approaches.For example,in the target area of any size,the coverage rate and the repeated coverage rate of the proposed multi-UAVs scheduling are improved by 6.9–29.1%,and 2.0–56.1%,respectively.Moreover,the proposed scheduling algorithm is high adaptable to diverse execution environments.©2022 Published by Elsevier Ltd. 展开更多
关键词 Multi-UAVs Ad hoc network Area collaborative coverage Gravity model Swarm optimization algorithm Random topology
下载PDF
Map-based cloning of q LP_(A01.1),a favorable allele from the Gossypium tomentosum chromosome segment line
11
作者 Wenwen Wang lei chen +9 位作者 Yan Wu Xin Guo Jinming Yang Dexin Liu Xueying Liu Kai Guo Dajun Liu Zhonghua Teng Yuehua Xiao Zhengsheng Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3283-3293,共11页
Cotton is an important natural fiber crop worldwide which plays a vital role in our daily life.High yield is a constant goal of cotton breeding,and lint percentage(LP)is one of the important components of cotton fiber... Cotton is an important natural fiber crop worldwide which plays a vital role in our daily life.High yield is a constant goal of cotton breeding,and lint percentage(LP)is one of the important components of cotton fiber yield.A stable QTL controlling LP,qLP_(A01.1),was identified on chromosome A01 from Gossypium hirsutum introgressed lines with G.tomentosum chromosome segments in a previous study.To fine-map qLP_(A01.1),an F2 population with 986individuals was established by crossing G.hirsutum cultivar CCRI35 with the chromosome segment substitution line HT_390.A high-resolution genetic map including 47 loci and spanning 56.98 cM was constructed in the QTL region,and qLP_(A01.1)was ultimately mapped into an interval corresponding to an~80 kb genome region of chromosome A01in the reference genome,which contained six annotated genes.Transcriptome data and sequence analysis revealed that S-acyltransferase protein 24(GoPAT24)might be the target gene of qLP_(A01.1).This result provides the basis for cotton fiber yield improvement via marker-assisted selection(MAS)and further studies on the mechanism of cotton fiber development. 展开更多
关键词 cotton lint percentage FINE-MAPPING qLPA01.1 GoPAT24
下载PDF
Hollow Metal-Organic Framework/MXene/Nanocellulose Composite Films for Giga/Terahertz Electromagnetic Shielding and Photothermal Conversion
12
作者 Tian Mai lei chen +2 位作者 Pei‑Lin Wang Qi Liu Ming‑Guo Ma 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期161-179,共19页
With the continuous advancement of communication technology,the escalating demand for electromagnetic shielding interference(EMI)materials with multifunctional and wideband EMI performance has become urgent.Controllin... With the continuous advancement of communication technology,the escalating demand for electromagnetic shielding interference(EMI)materials with multifunctional and wideband EMI performance has become urgent.Controlling the electrical and magnetic components and designing the EMI material structure have attracted extensive interest,but remain a huge challenge.Herein,we reported the alternating electromagnetic structure composite films composed of hollow metal-organic frameworks/layered MXene/nanocellulose(HMN)by alternating vacuum-assisted filtration process.The HMN composite films exhibit excellent EMI shielding effectiveness performance in the GHz frequency(66.8 dB at Kaband)and THz frequency(114.6 dB at 0.1-4.0 THz).Besides,the HMN composite films also exhibit a high reflection loss of 39.7 dB at 0.7 THz with an effective absorption bandwidth up to 2.1 THz.Moreover,HMN composite films show remarkable photothermal conversion performance,which can reach 104.6℃under 2.0 Sun and 235.4℃under 0.8 W cm^(−2),respectively.The unique micro-and macrostructural design structures will absorb more incident electromagnetic waves via interfacial polarization/multiple scattering and produce more heat energy via the local surface plasmon resonance effect.These features make the HMN composite film a promising candidate for advanced EMI devices for future 6G communication and the protection of electronic equipment in cold environments. 展开更多
关键词 Metal-organic frameworks MXene NANOCELLULOSE Electromagnetic shielding Photothermal conversion
下载PDF
Discrimination of polysorbate 20 by high-performance liquid chromatography-charged aerosol detection and characterization for components by expanding compound database and library
13
作者 Shi-Qi Wang Xun Zhao +10 位作者 Li-Jun Zhang Yue-Mei Zhao lei chen Jin-Lin Zhang Bao-cheng Wang Sheng Tang Tom Yuan Yaozuo Yuan Mei Zhang Hian Kee Lee Hai-Wei Shi 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第5期722-732,共11页
Analyzing polysorbate 20(PS20)composition and the impact of each component on stability and safety is crucial due to formulation variations and individual tolerance.The similar structures and polarities of PS20 compon... Analyzing polysorbate 20(PS20)composition and the impact of each component on stability and safety is crucial due to formulation variations and individual tolerance.The similar structures and polarities of PS20 components make accurate separation,identification,and quantification challenging.In this work,a high-resolution quantitative method was developed using single-dimensional high-performance liquid chromatography(HPLC)with charged aerosol detection(CAD)to separate 18 key components with multiple esters.The separated components were characterized by ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UHPLC-Q-TOF-MS)with an identical gradient as the HPLC-CAD analysis.The polysorbate compound database and library were expanded over 7-time compared to the commercial database.The method investigated differences in PS20 samples from various origins and grades for different dosage forms to evaluate the composition-process relationship.UHPLC-Q-TOF-MS identified 1329 to 1511 compounds in 4 batches of PS20 from different sources.The method observed the impact of 4 degradation conditions on peak components,identifying stable components and their tendencies to change.HPLC-CAD and UHPLC-Q-TOF-MS results provided insights into fingerprint differences,distinguishing quasi products. 展开更多
关键词 Polysorbate 20 Component DATABASE DISCRIMINATION Degradation
下载PDF
Identifying influential spreaders in complex networks based on density entropy and community structure
14
作者 苏湛 陈磊 +2 位作者 艾均 郑雨语 别娜 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期765-774,共10页
In recent years,exploring the relationship between community structure and node centrality in complex networks has gained significant attention from researchers,given its fundamental theoretical significance and pract... In recent years,exploring the relationship between community structure and node centrality in complex networks has gained significant attention from researchers,given its fundamental theoretical significance and practical implications.To address the impact of network communities on target nodes and effectively identify highly influential nodes with strong propagation capabilities,this paper proposes a novel influential spreaders identification algorithm based on density entropy and community structure(DECS).The proposed method initially integrates a community detection algorithm to obtain the community partition results of the networks.It then comprehensively considers the internal and external density entropies and degree centrality of the target node to evaluate its influence.Experimental validation is conducted on eight networks of varying sizes through susceptible–infected–recovered(SIR)propagation experiments and network static attack experiments.The experimental results demonstrate that the proposed method outperforms five other node centrality methods under the same comparative conditions,particularly in terms of information spreading capability,thereby enhancing the accurate identification of critical nodes in networks. 展开更多
关键词 CORRIGENDUM electron impact ionization cross sections carbon monoxide
原文传递
Punicalagin prevents obesity-related cardiac dysfunction through promoting DNA demethylation in mice
15
作者 Shengjie Pei Run Liu +10 位作者 Qingqing Ma Peng Jiang Xin He Zhongshi Qi Jiacheng Fang Xu Yang Zirui Yao Xiaoqian Liu Xianfeng Jing lei chen Duo Li 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1465-1474,共10页
The aim of this study was to investigate whether punicalagin(PU)could prevent obesity-related cardiac dysfunction by promoting DNA demethy lation,and to explore its possible mechanism.C57BL/6J mice were fed with stand... The aim of this study was to investigate whether punicalagin(PU)could prevent obesity-related cardiac dysfunction by promoting DNA demethy lation,and to explore its possible mechanism.C57BL/6J mice were fed with standard diet,high-fat diet(HFD),HFD supplemented with resveratrol,low-dose PU(LPU)and high-dose PU(HPU)for 8 weeks.Compared with HFD group,body weight was significantly lower in PU treatment groups,number of cardionwocytes and the protein level of myosin heavy chain 7B were significantly higher in PU treatment groups.Levels of 5-hydroxymethylcytosine and 5-formylcytosine were significantly lower in HFD group than in other groups.Compared with the HFD group,the protein level of ten-eleven translocation enzyme(TET)2 was significantly higher in PU treatment groups,p-AMP-activated protein kinase(AMPK)was significantly higher in LPU group.Levels of total antioxidant capacity and the protein levels of complexesⅡ/Ⅲ/Ⅴ,oxoglutarate dehydrogenase,succinate dehydrogenase B and fumarate hdrolase were significantly lower in HFD group than PU treatment group.The ratio of(succinic acid+fumaric acid)/a-ketoglutarate was significantly higher in HFD group than other groups.In conclusion,PU up-regulated TETs enzyme activities and TET2 protein stability through alleviating mitochondrial dysfunction and activating AMPK,so as to promote DNA demethylation,thus preventing obesity-related cardiac dysfunction. 展开更多
关键词 DNA demethylation Mitochondrial function Obesity-related cardiac dysfunction PUNICALAGIN Ten-eleven translocation family enzymes
下载PDF
Manipulation of band gap in 1T-TiSe_(2) via rubidium deposition
16
作者 欧仪 陈磊 +6 位作者 信子鸣 任宇靖 袁鹏浩 王政国 朱玉 陈景芝 张焱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期102-106,共5页
The 1T-TiSe_(2) is a two-dimensional charge-density-wave(CDW)material that attracts great interest.A small band gap locates at the Fermi level separating the Ti d-bands and Se p-bands,which makes 1T-TiSe_(2) a promisi... The 1T-TiSe_(2) is a two-dimensional charge-density-wave(CDW)material that attracts great interest.A small band gap locates at the Fermi level separating the Ti d-bands and Se p-bands,which makes 1T-TiSe_(2) a promising candidate for realizing excitonic condensation.Here,we studied the band gap in 1T-TiSe_(2) using angle-resolved photoemission spectroscopy(ARPES).Instead of only focusing on the in-plane band dispersions,we obtained the detailed band dispersions of both conduction and valance bands along the out-of-plane direction.We found that the conduction and valance bands split into multiple sub-bands in the CDW state due to band folding.As a result,the band gap between the Ti d-bands and Se p-bands reduces to~25 meV and becomes a direct gap in the CDW state.More intriguingly,such band gap can be further reduced by the rubidium deposition.The band structure becomes semimetallic in the rubidium-doped sample.Meanwhile,exotic gapless behaviors were observed at the p-d band crossing.Our result characterized the band gap of 1T-TiSe_(2) in three-dimensional Brillouin zone with unpreceded precision.It also suggests a closing of band gap or a potential band inversion in 1T-TiSe_(2) driven by rubidium deposition. 展开更多
关键词 angle-resolved photoemission spectroscopy metal–insulator transition transition metal dichalcogenides
原文传递
聚多巴胺包覆硅化胶原的光热及抗菌性能研究
17
作者 张江山 雷晨 +3 位作者 伏雨桐 马雨轩 慕昭 陈吉华 《实用口腔医学杂志》 CAS CSCD 北大核心 2024年第4期461-466,共6页
目的:通过多巴胺聚合作用构建聚多巴胺包覆硅化胶原(SC@PDA),探究该材料光热杀菌作用与生物安全性。方法:通过聚合反应将多巴胺包覆在硅化胶原表面构建SC@PDA。用扫描电镜、透射电镜观察SC@PDA表面形貌,硅酸释放实验检测材料硅酸缓释情... 目的:通过多巴胺聚合作用构建聚多巴胺包覆硅化胶原(SC@PDA),探究该材料光热杀菌作用与生物安全性。方法:通过聚合反应将多巴胺包覆在硅化胶原表面构建SC@PDA。用扫描电镜、透射电镜观察SC@PDA表面形貌,硅酸释放实验检测材料硅酸缓释情况,808 nm激光照射与红外热像仪检测材料光热性能。CCK-8实验测试材料对大鼠骨髓间充质干细胞的毒性,急性全身毒性实验评价材料对大鼠的生物安全性。以SD大鼠为研究模型进行抗菌性能测试。将材料分别与金黄色葡萄球菌及大肠杆菌共培养6 h后,用808 nm激光(1.5 W/cm^(2))照射10 min,之后继续培养6 h,用吸光度检测计算材料光热抑菌率。在大鼠股骨缺损感染模型中观察材料植入缺损部位7 d后材料的抗感染效果。结果:SC@PDA具有良好的光热性能,保持了硅化胶原的硅酸缓释性能,无细胞毒性,无急性全身毒性。体内外抗菌实验表明,SC@PDA具有良好的光热抗菌能力。结论:SC@PDA具有优良的生物相容性,同时多巴胺包覆赋予了硅化胶原支架优异的光热抗菌性能。 展开更多
关键词 聚多巴胺 胶原支架 植入物相关感染 抗菌材料
下载PDF
A Cascading Fault Path Prediction Method for Integrated Energy Distribution Networks Based on the Improved OPA Model under Typhoon Disasters
18
作者 Yue He YaxiongYou +4 位作者 ZhianHe Haiying Lu lei chen Yuqi Jiang Hongkun chen 《Energy Engineering》 EI 2024年第10期2825-2849,共25页
In recent times,the impact of typhoon disasters on integrated energy active distribution networks(IEADNs)has received increasing attention,particularly,in terms of effective cascading fault path prediction and enhance... In recent times,the impact of typhoon disasters on integrated energy active distribution networks(IEADNs)has received increasing attention,particularly,in terms of effective cascading fault path prediction and enhanced fault recovery performance.In this study,we propose a modified ORNL-PSerc-Alaska(OPA)model based on optimal power flow(OPF)calculation to forecast IEADN cascading fault paths.We first established the topology and operational model of the IEADNs,and the typical fault scenario was chosen according to the component fault probability and information entropy.The modified OPA model consisted of two layers:An upper-layer model to determine the cascading fault location and a lower-layer model to calculate the OPF by using Yalmip and CPLEX and provide the data to update the upper-layer model.The approach was validated via the modified IEEE 33-node distribution system and two real IEADNs.Simulation results showed that the fault trend forecasted by the novel OPA model corresponded well with the development and movement of the typhoon above the IEADN.The proposed model also increased the load recovery rate by>24%compared to the traditional OPA model. 展开更多
关键词 IEADNs OPA model cascading fault path prediction fault probability optimal power flow typical fault scenario
下载PDF
Biomechanical effects of posterior lumbar interbody fusion with vertical placement of pedicle screws compared to traditional placement
19
作者 Ji-Hong Jiang Chang-Ming Zhao +2 位作者 Jun Zhang Rong-Ming Xu lei chen 《World Journal of Clinical Cases》 SCIE 2024年第20期4108-4120,共13页
BACKGROUND The pedicle screw technique is widely employed for vertebral body fixation in the treatment of spinal disorders.However,traditional screw placement methods require the dissection of paraspinal muscles and t... BACKGROUND The pedicle screw technique is widely employed for vertebral body fixation in the treatment of spinal disorders.However,traditional screw placement methods require the dissection of paraspinal muscles and the insertion of pedicle screws at specific transverse section angles(TSA).Larger TSA angles require more force to pull the muscle tissue,which can increase the risk of surgical trauma and ischemic injury to the lumbar muscles.AIM To study the feasibility of zero-degree TSA vertical pedicle screw technique in the lumbosacral segment.METHODS Finite element models of vertebral bodies and pedicle screw-rod systems were established for the L4-S1 spinal segments.A standard axial load of 500 N and a rotational torque of 10 N/m were applied.Simulated screw pull-out experiment was conducted to observe pedicle screw resistance to pull-out,maximum stress,load-displacement ratio,maximum stress in vertebral bodies,load-displacement ratio in vertebral bodies,and the stress distribution in pedicle screws and vertebral bodies.Differences between the 0-degree and 17-degree TSA were compared.RESULTS At 0-degree TSA,the screw pull-out force decreased by 11.35%compared to that at 17-degree TSA(P<0.05).At 0-degree and 17-degree TSA,the stress range in the screw-rod system was 335.1-657.5 MPa and 242.8-648.5 MPa,separately,which were below the fracture threshold for the screw-rod system(924 MPa).At 0-degree and 17-degree TSA,the stress range in the vertebral bodies was 68.45-78.91 MPa and 39.08-72.73 MPa,separately,which were below the typical bone yield stress range for vertebral bodies(110-125 MPa).At 0-degree TSA,the load-displacement ratio for the vertebral bodies and pedicle screws was slightly lower compared to that at 17-degree TSA,indicating slightly lower stability(P<0.05).CONCLUSION The safety and stability of 0-degree TSA are slightly lower,but the risks of screw-rod system fracture,vertebral body fracture,and rupture are within acceptable limits. 展开更多
关键词 Vertical pedicle screw Pedicle screw technique Transverse section angle Lumbosacral segment Finite element analysis
下载PDF
Prognostic value and predictive model of tumor markers in stageⅠtoⅢgastric cancer patients
20
作者 Ai-Hua Sun Xin-Yu Zhang +3 位作者 Yang-Yang Huang lei chen Qing Wang Xiao-Cong Jiang 《World Journal of Clinical Oncology》 2024年第8期1033-1047,共15页
BACKGROUND Preoperative serum tumor markers have been widely used in the diagnosis and treatment of gastric cancer patients.However,few studies have evaluated the prognosis of gastric cancer patients by establishing s... BACKGROUND Preoperative serum tumor markers have been widely used in the diagnosis and treatment of gastric cancer patients.However,few studies have evaluated the prognosis of gastric cancer patients by establishing statistical models with multiple serum tumor indicators.AIM To explore the prognostic value and predictive model of tumor markers in stage I and III gastric cancer patients.METHODS From October 2018 to April 2020,a total of 1236 patients with stage I to III gastric cancer after surgery were included in our study.The relationship between serum tumor markers and clinical and pathological data were analyzed.We established a statistical model to predict the prognosis of gastric cancer based on the results of COX regression analysis.Overall survival(OS)was also compared across different stages of gastric cancer.RESULTS The deadline for follow-up was May 31,2023.A total of 1236 patients were included in our study.Univariate analysis found that age,clinical stage,T and N stage,tumor location,differentiation,Borrmann type,size,and four serum tumor markers were prognostic factors of OS(P<0.05).It was shown that clinical stage,tumor size,alpha foetoprotein,carcinoembryonic antigen,CA125 and CA19-9(P<0.05)were independent prognostic factors for OS.According to the scoring results obtained from the statistical model,we found that patients with high scores had poorer survival time(P<0.05).Furthermore,in stage I patients,the 3-year OS for scores 0-3 ranged from 96.85%,95%,85%,and 80%.In stage II patients,the 3-year OS for scores 0-4 were 88.6%,76.5%,90.5%,65.5%and 60%.For stage III patients,3-year OS for scores 0-6 were 70.9%,68.3%,64.1%,50.9%,38.4%,18.5%and 5.2%.We also analyzed the mean survival of patients with different scores.For stage I patients,the mean OS was 55.980 months.In stage II,the mean OS was 51.550 months.The mean OS for stage III was 39.422 months.CONCLUSION Our statistical model can effectively predict the prognosis of gastric cancer patients. 展开更多
关键词 Gastric cancer Tumor marker PROGNOSIS Overall survival Model
下载PDF
上一页 1 2 27 下一页 到第
使用帮助 返回顶部