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杂萘联苯聚芳醚系列高性能树脂的构筑与应用
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作者 刘乾 程习彤 +5 位作者 贺翼平 石鹏 刘程 王锦艳 张守海 蹇锡高 《高分子学报》 北大核心 2026年第1期6-22,共17页
高性能聚合物是航空航天、能源电子等行业发展的重要材料.如何通过分子设计,对聚合物功能材料的微结构和性能进行精准调控,提升目标器件的综合性能是高性能聚合物研究的重要课题与研究前沿.本文简要介绍了作者团队在杂萘联苯聚芳醚系列... 高性能聚合物是航空航天、能源电子等行业发展的重要材料.如何通过分子设计,对聚合物功能材料的微结构和性能进行精准调控,提升目标器件的综合性能是高性能聚合物研究的重要课题与研究前沿.本文简要介绍了作者团队在杂萘联苯聚芳醚系列高性能工程塑料的合成与性能及其在高性能树脂基复合材料、绝缘材料、耐高温功能膜、热固性树脂的增韧、电化学储能装置以及骨植入材料等领域的研究进展.从分子设计出发,首先成功研制具有扭曲、非平面结构特点的含杂萘联苯结构的新型单体,进而与双卤单体经亲核取代逐步聚合反应合成了多系列含杂萘联苯结构新型聚芳醚类高性能工程塑料.该系列材料兼具良好溶解性和耐热性,突破了传统高性能工程塑料耐热性和难溶解耦合技术难题,不仅实现高性能聚合物制备成本的下降,还进一步实现高性能聚合物的溶液加工.其玻璃化转变温度达250~388℃,5%热失重起始温度均高于500℃,可溶解于N-甲基吡咯烷酮、N,N-二甲基乙酰胺以及氯仿等几种有机溶剂;在高温下依然保持优异的综合性能;可广泛应用于航空航天、核能、电子电气等高技术领域和国民经济众多行业. 展开更多
关键词 杂萘联苯 高性能树脂 杂环聚芳醚 高分子材料 分子设计
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氨基己内酰胺在不同溶剂中的溶解度测定及关联
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作者 郭晓杰 石鹏 +3 位作者 任强 王春璐 丁素萍 郑博 《过程工程学报》 北大核心 2026年第3期289-302,共14页
氨基己内酰胺作为一种重要的有机化工中间体,其溶解度的测定是溶液结晶纯化技术开发和产品质量控制的热力学基础。本工作采用静态平衡法测定了氨基己内酰胺在N,N-二甲基甲酰胺、丙酮、1,4-二氧六环、磷酸三辛酯、甲苯、对二甲苯、1,3,5... 氨基己内酰胺作为一种重要的有机化工中间体,其溶解度的测定是溶液结晶纯化技术开发和产品质量控制的热力学基础。本工作采用静态平衡法测定了氨基己内酰胺在N,N-二甲基甲酰胺、丙酮、1,4-二氧六环、磷酸三辛酯、甲苯、对二甲苯、1,3,5-三甲苯、甲基叔丁基醚、环己烷和正己烷等有机溶剂中的溶解度。结果表明,在278.15~323.15 K温度范围内,氨基己内酰胺在不同溶剂中的溶解度随温度升高而增大,且在不同溶剂中的溶解度基本符合随溶剂极性增大而增大的规律。但该规律存在个别例外,甲基叔丁基醚虽具有一定极性,理论上可与氨基己内酰胺形成静电相互作用,但其分子结构带来的空间位阻显著阻碍了溶质与溶剂间的有效相互作用,导致氨基己内酰胺在该溶剂中的溶解度偏低;而甲苯等芳香烃溶剂可通过离域π电子云与氨基己内酰胺的共轭区域形成电子云重叠,从而增强溶解性。这表明除极性外,溶质-溶剂电子云重叠等因素也会影响溶解行为。采用Apelblat、λh、二次多项式和Van't Hoff模型对溶解度数据进行拟合,所有模型的相关系数(R^(2))均大于0.95。其中二次多项式模型的拟合效果最佳,平均相对偏差ARD为0~1.8403%,均方根偏差RMSD为0~0.3190%。通过Van't Hoff方程分析溶解过程的热力学参数,显示在正己烷和环己烷两种非极性溶剂中氨基己内酰胺的Δ_(dis) H,Δ_(dis) S和Δ_(dis) G均为正值,表明其溶解过程是非自发的吸热熵增过程。计算得出焓相对贡献ζ_(H)小于熵相对贡献ζ_(TS),表明其在这10种溶剂的溶解过程中,Δ_(dis)H对Δ_(dis)G的贡献小于Δ_(dis)S。 展开更多
关键词 氨基己内酰胺 溶解度 模型拟合 溶解热力学性质
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Toughening response of simulated CGHAZ under low welding heat input for a micro-alloyed steel and failure mechanisms
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作者 Xian-Guang Zhang Shou-Li Feng +3 位作者 Jiang-Hua Qi peng shi Chun-Yang Shu Huang-Xun Guo 《Journal of Iron and Steel Research International》 2026年第3期235-250,共16页
Low heat input welding is widely used in the industry.The microstructure and toughness of the welded joints under low heat input conditions have received less attention than those under high heat input.The impact toug... Low heat input welding is widely used in the industry.The microstructure and toughness of the welded joints under low heat input conditions have received less attention than those under high heat input.The impact toughness,microstructure and failure mechanisms of the coarse-grain heat-affected zone(CGHAZ)in a micro-alloyed steel were investigated by welding thermal simulation with the heat input ranging from 15 to 65 kJ/cm.The impact toughness of CGHAZ is highly sensitive to variations in low heat input.The failure mechanisms were discussed from the viewpoints of micro-voids formation and micro-cracks propagation.The micro-voids are preferred to be formed and grow at soft phase of grain boundary ferrite(GBF).At the heat inputs no more than 22 kJ/cm,martensite was dominantly formed,and the micro-cracks initiated from the GBF were propagated into the grain interiors,leading to the brittle fracture and low toughness.When the heat input was increased to 31.2 kJ/cm,granular bainite became the dominant constitute,causing cracks to deflect away from GBF and propagate into prior austenite grains.The high density high-angle and low-angle grain boundaries and the presence of retained austenite,effectively restricted the crack propagation,resulting in ductile fracture behavior and enhanced toughness.High heat input(62.3 kJ/cm)promoted coarse GBF formation,providing continuous paths for microcrack propagation.This direct intergranular crack progression caused brittle fracture and low toughness.Industrial cold cracking in the CGHAZ can thus be controlled by heat input optimization to maximize toughness. 展开更多
关键词 Micro-alloyed steel Low heat input welding TOUGHNESS Microstructure Cold cracking
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Phylogenetic relationships of the zokor genus Eospalax(Mammalia,Rodentia,Spalacidae)inferred from whole-genome analyses,with description of a new species endemic to Hengduan Mountains 被引量:4
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作者 Tao Zhang Meng-Long Lei +2 位作者 Hao Zhou Zhong-Zheng Chen peng shi 《Zoological Research》 SCIE CAS CSCD 2022年第3期331-342,共12页
Zokors in the genus Eospalax,which are endemic to northern and western China,are subterranean rodents that inhabit various niches,including grasslands,high-altitude meadows,forests,and farmlands.Six species in Eospala... Zokors in the genus Eospalax,which are endemic to northern and western China,are subterranean rodents that inhabit various niches,including grasslands,high-altitude meadows,forests,and farmlands.Six species in Eospalax were described a century ago but their taxonomy and phylogeny remain controversial.In this study,we performed high-depth whole-genome sequencing of 47 zokor samples,comprising all six previously described species.Genomic analyses revealed a reliable and robust phylogeny of Eospalax and supported the validity of the six named species.According to the inferred phylogenetic relationships,Eospalax first divergent into two clades in the early Pliocene(ca.4.68 million years ago(Ma)),one inhabiting the highaltitude Qinghai-Xizang(Tibet)Plateau(QTP)and adjacent regions,and the another inhabiting the lowaltitude Loess Plateau and Qinling-Daba Mountains.The most recent divergences occurred between E.baileyi and E.smithii and between E.rufescens and E.rothschildi in the late Pliocene(ca.2.09 and 2.19 Ma,respectively).We also collected specimens of zokors in the southern Hengduan Mountains(Muli County,Sichuan Province),far from the known distributions of all other zokors.Morphological and molecular analyses strongly suggested that the specimens represent a new species,formally described here as Eospalax muliensis sp.nov.The new species belongs to the high-altitude clade and diverged from closely related species(ca.4.22 Ma)shortly after the first divergence in Eospalax.Interestingly,Eospalax muliensis sp.nov.possesses more supposedly plesiomorphic characters,suggesting a possible origin of the genus in the Hengduan Mountains. 展开更多
关键词 ZOKOR Eospalax Phylogenomic analyses New species Hengduan Mountains
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Experimental study of relationship between average isotopic fractionation factor and evaporation rate 被引量:1
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作者 Tao WANG Wei-min BAO +6 位作者 Hai-li XU Zhen ZHU Si-min QU peng shi Hai-ying HU Rui-qi FAN Qian LI 《Water Science and Engineering》 EI CAS 2010年第4期394-404,共11页
Isotopic fractionation is the basis of tracing the water cycle using hydrogen and oxygen isotopes. Isotopic fractionation factors in water evaporating from free water bodies are mainly affected by temperature and rela... Isotopic fractionation is the basis of tracing the water cycle using hydrogen and oxygen isotopes. Isotopic fractionation factors in water evaporating from free water bodies are mainly affected by temperature and relative humidity, and vary significantly with these atmospheric factors over the course of a day. The evaporation rate (E) can reveal the effects of atmospheric factors. Therefore, there should be a certain functional relationship between isotopic fractionation factors and E. An average isotopic fractionation factor ( t~* ) was defined to describe isotopic differences between vapor and liquid phases in evaporation with time intervals of days. The relationship between or* and E based on the isotopic mass balance was investigated through an evaporation pan experiment with no inflow. The experimental results showed that the isotopic compositions of residual water were more enriched with time; tr* was affected by air temperature, relative humidity, and other atmospheric factors, and had a strong functional relation with E. The values of 0~* can be easily calculated with the known values of E, the initial volume of water in the pan, and isotopic compositions of residual water. 展开更多
关键词 average isotopic fractionation factor evaporation rate hydrogen and oxygen isotopes
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基于CHP物理特性等值建模的气-电-热混合能流统一分析方法
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作者 彭石 谢宁 +1 位作者 王承民 田沛川 《中国电机工程学报》 北大核心 2025年第7期2579-2593,I0011,共16页
针对燃气-蒸汽联合循环且余热锅炉不补燃的热电联产机组(combined power and heat unit,CHP),首先,基于能量守恒建立天然气流量与电力电压、电流的等值关系,进而考虑功率进行变换的物理特性,构建CHP的气电变换等效电路;考虑功率进行传... 针对燃气-蒸汽联合循环且余热锅炉不补燃的热电联产机组(combined power and heat unit,CHP),首先,基于能量守恒建立天然气流量与电力电压、电流的等值关系,进而考虑功率进行变换的物理特性,构建CHP的气电变换等效电路;考虑功率进行传递、释放的物理特性,构建CHP的气热转换、烟气排放及运行热损失方程;据此,确立CHP的物理特性等值模型,并定义该模型“以热定电”和“以电定热”策略下的控制参量。其次,利用牛顿法和管网水力计算基本原理,推导电潮流和气、热能流的修正方程及其雅可比元素表达式,提出计及CHP固有特性参数随系统运行状态变化的气-电-热混合能流统一分析方法。最后,通过具有不同CHP控制策略的气-电-热混合系统,验证所提方法的有效性及可行性。 展开更多
关键词 燃气-蒸汽联合循环 余热锅炉 气电变换 气热转换 烟气排放 CHP物理特性等值模型 气-电-热混合能流统一分析
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流动电极电容去离子技术去除土壤中的六价铬
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作者 金锐 徐婷婷 +1 位作者 彭石 何云峰 《环境科学与技术》 北大核心 2025年第S2期181-191,共11页
目前主流的土壤铬污染修复技术难以完全去除Cr(Ⅵ),且存在二次污染问题。流动电极电容去离子技术(flow-electrode capacitive deionization,FCDI)是一种对环境友好的新兴修复技术,已在废水处理和资源回收领域得到了应用,但对Cr(Ⅵ)污染... 目前主流的土壤铬污染修复技术难以完全去除Cr(Ⅵ),且存在二次污染问题。流动电极电容去离子技术(flow-electrode capacitive deionization,FCDI)是一种对环境友好的新兴修复技术,已在废水处理和资源回收领域得到了应用,但对Cr(Ⅵ)污染土壤的修复效果尚未报道过。该研究将高岭土、K2Cr2O7和炭黑等混合作为FCDI的阴极,研究了FCDI去除高岭土中Cr(Ⅵ)的可行性,通过多种表征方法对系统中炭黑的作用进行了分析,并对运行参数进行了优化,最后考察了其在Cr(Ⅵ)污染场地土壤中的修复效果。结果表明:FCDI对高岭土中Cr(Ⅵ)的去除率达到75%以上,炭黑的加入增强了Cr(Ⅵ)的吸附作用,并且增加了电荷传递速率;优选运行参数为炭黑含量为10 g/L,p H为5,电流密度为3 A/m^(2),KCl浓度为500 mg/L;FCDI对Cr(Ⅵ)污染场地土壤具有良好的修复效果,在优选运行参数下运行1 h后,污染场地土壤中的Cr(Ⅵ)去除率可达59.1%,且修复后Cr的整体赋存形态更为稳定。研究可为FCDI在土壤污染修复方面的应用提供新思路。 展开更多
关键词 流动电极电容去离子技术 六价铬 炭黑 高岭土 土壤修复
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血清LPCAT3对HBV相关肝细胞癌患者的诊断价值
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作者 张烨 彭适 +1 位作者 汤冬玲 张平安 《中西医结合肝病杂志》 2025年第2期159-162,共4页
目的:评估溶血磷脂酰胆碱酰基转移酶3(LPCAT3)对乙型肝炎病毒(HBV)相关肝细胞癌(HCC)患者的诊断价值。方法:收集2022年3月至2023年8月在武汉大学人民医院肿瘤科、传染科就诊的90例HBV相关性HCC患者(HBV-HCC组)、52例HBV感染后肝硬化患者... 目的:评估溶血磷脂酰胆碱酰基转移酶3(LPCAT3)对乙型肝炎病毒(HBV)相关肝细胞癌(HCC)患者的诊断价值。方法:收集2022年3月至2023年8月在武汉大学人民医院肿瘤科、传染科就诊的90例HBV相关性HCC患者(HBV-HCC组)、52例HBV感染后肝硬化患者(HBV-LC组)及体检中心49例健康体检者(对照组)的临床资料。比较各组人群血清LPCAT3及甲胎蛋白(AFP)水平,采用受试者工作特征曲线分析LPCAT3和AFP单独及联合检测对肝细胞癌的诊断价值。结果:对照组、HBV-LC组、HBV-HCC组血清LPCAT3和AFP水平依次增加,差异均有统计学意义(P<0.05)。HBV-HCC组与对照组进行鉴别诊断时,LPCAT3的曲线下面积(AUC)为1.000,敏感度和特异度均为100.00%;而AFP的AUC为0.842,敏感度65.60%,特异度100.00%;两者联合检测时AUC为1.000,特异度和灵敏度都为100.00%。HBV-HCC组与HBV-LC组鉴别诊断时,LPCAT3和AFP单独及联合检测的AUC分别为0.765、0.768和0.802。AFP阴性的HBV-HCC患者与其他组进行鉴别诊断,LPCAT3的AUC为0.831。结论:LPCAT3诊断HBV-HCC时其诊断价值强于AFP,且LPCAT3与AFP联合检测能提高HBV-HCC的诊断效率。 展开更多
关键词 乙型肝炎病毒 肝细胞癌 甲胎蛋白 溶血磷脂酰胆碱酰基转移酶3
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医学生对教师的满意度与职业认同感的关系研究——基于汕头大学医学生的调查数据分析
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作者 彭施 柳禧姿 +3 位作者 李元清 李韵 林常敏 杨苗 《中国高等医学教育》 2025年第12期31-33,共3页
目的:探究医学生对教师的满意度与职业认同感的现状与相关性。方法:基于2023年CMSS数据库中汕头大学医学院2816名本科生对教师的满意度、职业认同感的数据进行分析。结果:汕头大学医学生对教师的满意度总分为(4.02±0.62)分,职业认... 目的:探究医学生对教师的满意度与职业认同感的现状与相关性。方法:基于2023年CMSS数据库中汕头大学医学院2816名本科生对教师的满意度、职业认同感的数据进行分析。结果:汕头大学医学生对教师的满意度总分为(4.02±0.62)分,职业认同感总分为(3.88±0.67)分;医学生对教师的满意度及各个维度与职业认同感及各个维度呈显著正相关(r=0.43~0.56,均为P<0.001);结论:医学生对教师的满意度与职业认同感呈正相关关系;对教师满意度中的师德师风、教学水平、学术水平和育人意识均对医学生的职业认同感产生独立影响,教育工作者可以从这4个维度增强医学生的职业认同感。 展开更多
关键词 对教师的满意度 医学生 职业认同感
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Improved Event-Triggered Adaptive Neural Network Control for Multi-agent Systems Under Denial-of-Service Attacks 被引量:2
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作者 Huiyan ZHANG Yu HUANG +1 位作者 Ning ZHAO peng shi 《Artificial Intelligence Science and Engineering》 2025年第2期122-133,共12页
This paper addresses the consensus problem of nonlinear multi-agent systems subject to external disturbances and uncertainties under denial-ofservice(DoS)attacks.Firstly,an observer-based state feedback control method... This paper addresses the consensus problem of nonlinear multi-agent systems subject to external disturbances and uncertainties under denial-ofservice(DoS)attacks.Firstly,an observer-based state feedback control method is employed to achieve secure control by estimating the system's state in real time.Secondly,by combining a memory-based adaptive eventtriggered mechanism with neural networks,the paper aims to approximate the nonlinear terms in the networked system and efficiently conserve system resources.Finally,based on a two-degree-of-freedom model of a vehicle affected by crosswinds,this paper constructs a multi-unmanned ground vehicle(Multi-UGV)system to validate the effectiveness of the proposed method.Simulation results show that the proposed control strategy can effectively handle external disturbances such as crosswinds in practical applications,ensuring the stability and reliable operation of the Multi-UGV system. 展开更多
关键词 multi-agent systems neural network DoS attacks memory-based adaptive event-triggered mechanism
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Clinical Guideline for Cleansing and Antisepsis in Chronic Wounds
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作者 Shouyu Wang Xiaohong Sun +3 位作者 Tianke Yang Huan Wang peng shi Xingkai Wang 《Journal of Clinical and Nursing Research》 2025年第12期16-20,共5页
This guideline summarizes evidence-based recommendations for cleansing and antisepsis in chronic wounds.It defines target populations,assessment and decision frameworks,preferred cleansing solutions and pressures,indi... This guideline summarizes evidence-based recommendations for cleansing and antisepsis in chronic wounds.It defines target populations,assessment and decision frameworks,preferred cleansing solutions and pressures,indications and limits for antiseptics,biofilm-oriented strategies,pain control,and adaptations for high-risk patients and low-resource settings.The aim is to optimize wound bed preparation,protect viable tissue,reduce infection and iatrogenic injury,and standardize outpatient and home-care practice. 展开更多
关键词 Chronic wounds Wound cleansing ANTISEPSIS Irrigation solutions Wound biofilm
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Accelerating homogenization kinetics and enhancing hot-workability of as-cast nickel-based superalloy via prior hot-deformation
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作者 Jia-jun Chen Yang Zhou +8 位作者 Hao-ran Han Xian-guang Zhang Goro Miyamoto Ping-mei Tang Dong-ping Xiao Jian-hui Fu peng shi Yi-wu Pei Jian Zhang 《Journal of Iron and Steel Research International》 2025年第1期215-226,共12页
Enhancing homogenization efficiency and hot-workability is the key issue for wrought superalloys in the industry.A novel approach for simultaneous accelerating the homogenization kinetics and improving hot-workability... Enhancing homogenization efficiency and hot-workability is the key issue for wrought superalloys in the industry.A novel approach for simultaneous accelerating the homogenization kinetics and improving hot-workability via a simple way of prior hot-deformation was proposed,which was not widely accepted for wrought superalloys.The homogenization efficiency is increased by 40%-70%via performing 10%-20%prior hot-deformation.Both theoretical and experimental analyses revealed that the increment in homogenization efficiency is mainly attributed to the decrease in interdendritic-segregation spacing,and thus the necessary diffusion distance,rather than that of dislocations.In addition,dynamic and static recrystallizations occurred during the prior hot-deformation and diffusion-annealing processes,and the grains were significantly refined even after the homogenization.Furthermore,the size of the precipitates was refined as well.These enhanced the hot-workability of the homogenized ingot for the subsequent cogging process. 展开更多
关键词 Nickel-based superalloy Homogenization kinetics Prior hot-deformation Grain size Hot workability
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Molecular docking-driven anion coordination enabling SEI engineering for ultrastable all-solid-state lithium metal batteries
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作者 shihui Zou Xiaoxiang Deng +11 位作者 Ziang Ren peng shi Mengyang Li Juxin Yue Ke Yue Zihao Zhang Yao Wang Jianwei Nai Jianmin Luo Huadong Yuan Xinyong Tao Yujing Liu 《Journal of Energy Chemistry》 2025年第11期548-557,I0014,共11页
Regulating lithium(Li)salt decomposition to construct a stable solid electrolyte interphase(SEI)represents a pivotal strategy for mitigating Li dendrite and unlocking the full potential of polymer-based all-solid-stat... Regulating lithium(Li)salt decomposition to construct a stable solid electrolyte interphase(SEI)represents a pivotal strategy for mitigating Li dendrite and unlocking the full potential of polymer-based all-solid-state Li metal batteries.However,this approach necessitates precise manipulation of the coordination chemistry and decomposition kinetics of Li-salt anions,which remains a formidable challenge in the field.Herein,we unveil a molecular docking-guided design framework that correlates the molecular topology of ligands with bis(trifluoromethanesulfonyl)imide(TFSI-)anion coordination chemistry in poly(ethylene oxide)(PEO)-based solid polymer electrolytes.Theoretical calculations and experimental investigations elucidate that short-chain dithiols(e.g.,1,2-ethanedithiol,C2)exhibit optimal spatial complementarity and superior molecular docking efficacy with TFSI-compared to long-chain analogues.Intermolecular hydrogen bonding redistributes electron density toward TFSI-,promoting its decomposition and enhancing LiF content in the SEI,thereby effectively suppressing Li dendrite growth.Consequently,the Li||LiFePO_(4)cells equipped with PEO-LiTFSI-C2 electrolyte achieve a remarkable 99.2%capacity retention after 580 cycles at 1.0 C,surpassing both long-chain dithiol systems and most previously reported electrolytes.This work provides mechanistic insights into the anion-coordination-mediated SEI formation process.Furthermore,the molecular docking is expected to play a significant role in understanding and researching the interfacial chemistry of allsolid-state Li metal batteries. 展开更多
关键词 Solid-state batteries Li metal batteries SEI Molecular docking Anion coordination
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Research and application of thermosensitive Pickering emulsion with X-ray and ultrasound dual-modal imaging functions for intra-arterial embolization treatment
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作者 Ling Li Anran Guo +6 位作者 Haixia Sun Yanbing Zhao Qing Yao Ling Zhang peng shi Hongan Tian Min Zheng 《Journal of Pharmaceutical Analysis》 2025年第4期759-774,共16页
Transcatheter arterial embolization(TAE)is the mainstay for treating advanced hepatocellular carcinoma(HCC),and the performance of the embolization material is crucial in TAE.With the development of medical imaging an... Transcatheter arterial embolization(TAE)is the mainstay for treating advanced hepatocellular carcinoma(HCC),and the performance of the embolization material is crucial in TAE.With the development of medical imaging and the birth of“X-ray-free”technologies,we designed a new dual-mode imaging material of dimethoxy tetraphenyl ethylene(DMTPE)via emulsification by mixing poly(N-isopropylacrylamide-co-acrylic acid)(PNA)with lipiodol and fluorocarbons,which was evaluated for temperature sensitivity,stability,and dual-mode visualization in vitro.Additionally,blood vessel casting embolization and renal artery imaging were assessed in healthy rabbits.In a rabbit model with a VX2 tumor,the effectiveness of TAE for treating HCC was examined,with an emphasis on evaluating long-term outcomes of embolization and its effects on tumor growth,necrosis,and proliferation through imaging techniques.In vitro experiments confirmed that the temperature-sensitive dual-oil-phase Pickering emulsion had good flow,stable contrast,and embolism when the oil-to-oil ratio and water-to-oil ratio were both 7:3(v/v)and stabilized with 8%PNA.Similarly,in vivo,arterial embolization confirmed the excellent properties of DMTPE prepared at the abovementioned ratios.It was observed that DMTPE not only has an antitumor effect but can also achieve dual imaging using X-rays and ultrasound,making it a promising excellent vascular embolization material for TAE in tumor treatment. 展开更多
关键词 Dual-modal imaging Temperature sensitivity Pickering emulsion Transcatheter arterial embolization
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Clinical Research Progress of Crohn
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作者 Pingping Mei Wenzhe Feng +2 位作者 peng shi Yu Zhuang Wenxiu Zhang 《Journal of Biosciences and Medicines》 CAS 2022年第8期35-46,共12页
Crohn’s Disease (CD) is a chronic recurrent inflammatory bowel disease with unknown etiology, most common in the terminal ileum and adjacent colon. In the past 30 years, the global prevalence of CD has continued to r... Crohn’s Disease (CD) is a chronic recurrent inflammatory bowel disease with unknown etiology, most common in the terminal ileum and adjacent colon. In the past 30 years, the global prevalence of CD has continued to rise. Although the etiology is unknown, studies have shown that it is closely related to geographical environment, microfold cell damage, intestinal flora changes, epithelial barrier damage, immune dysfunction and low. The main clinical manifestations of CD are abdominal pain, chronic diarrhea, fatigue, fever and weight loss. At present, 5-aminosalicylic acid, antibiotics, glucocorticoids, immunosuppressants and biological agents are mainly used for treatment, but the drug effect is limited and the effect is not good. Recent studies have shown that Mesenchymal Stem Cells (MSC) can down-regulate immune response and promote tissue healing, which has certain safety and effectiveness in the treatment of moderate and severe CD, and has broad application prospects, but also has certain limitations. This paper summarizes the application and efficacy of related therapies in CD, providing a reference for clinicians. 展开更多
关键词 CROHN Crohn’s Drug Treatment Mesenchymal Stem Cells
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血清PKM2与PCT联合对脓毒症患者的诊断价值研究 被引量:7
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作者 王历 彭适 +2 位作者 蔡馨 汤冬玲 张平安 《疑难病杂志》 CAS 2023年第12期1233-1237,共5页
目的探讨血清丙酮酸激酶M2(PKM2)与降钙素原(PCT)对脓毒症的诊断价值。方法选取2022年4月—2023年1月武汉大学人民医院重症监护室(ICU)收治的脓毒症患者119例(脓毒症组),同期入住重症监护室的非脓毒症患者73例(非脓毒症组)作为研究对象... 目的探讨血清丙酮酸激酶M2(PKM2)与降钙素原(PCT)对脓毒症的诊断价值。方法选取2022年4月—2023年1月武汉大学人民医院重症监护室(ICU)收治的脓毒症患者119例(脓毒症组),同期入住重症监护室的非脓毒症患者73例(非脓毒症组)作为研究对象。入院24 h内检测并比较2组患者血清PKM2和PCT水平,采用Spearman相关性检验分析脓毒症患者血清PKM2与PCT水平的相关性;采用多因素Logistic回归模型分析各指标对脓毒症发生的影响;绘制受试者工作特征(ROC)曲线评价血清PKM2、PCT及二者联合对脓毒症的诊断价值,并计算曲线下面积(AUC)。结果与非脓毒症组比较,脓毒症组血清PKM2、PCT水平明显升高(Z/P=9.373/<0.001、9.013/<0.001)。脓毒症患者血清PKM2与PCT水平呈正相关(r=0.322,P<0.001)。多因素Logistic回归分析显示,血清PKM2、PCT水平升高均是脓毒症发生的独立危险因素[OR(95%CI)=1.182(1.078~1.295)、1.582(1.186~2.110)]。ROC曲线显示,血清PKM2、PCT及二者联合诊断脓毒症的AUC分别为0.903、0.888、0.941,敏感度分别为0.863、0.918、0.932,特异度分别为0.798、0.748、0.857,二者联合诊断的效能显著高于单独检测(Z/P=2.560/0.011、3.423/<0.001)。结论脓毒症患者血清PKM2水平升高,是脓毒症发生的独立危险因素,并与PCT呈正相关,二者联合检测具有较高诊断价值。 展开更多
关键词 脓毒症 丙酮酸激酶M2 降钙素原 诊断
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电气-供热管网系统等值模型与静态潮流分析方法 被引量:7
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作者 彭石 谢宁 +1 位作者 王承民 黄淳驿 《电力系统自动化》 EI CSCD 北大核心 2022年第13期62-73,共12页
随着光伏、风电等清洁能源的持续增长,电热混合系统将是未来综合能源系统的发展趋势。首先,建立供热管网系统流体质量流量与电力系统电功率的等值关系,保证电力功率流、热力流量流可以在统一的时域尺度下进行分析。在此基础上,分别构建... 随着光伏、风电等清洁能源的持续增长,电热混合系统将是未来综合能源系统的发展趋势。首先,建立供热管网系统流体质量流量与电力系统电功率的等值关系,保证电力功率流、热力流量流可以在统一的时域尺度下进行分析。在此基础上,分别构建供热管网系统的平均温度响应模型及电锅炉外特性模型,确立供热管网系统响应状态及电、热功率流间相互影响的变量。基于牛顿法和供热管网水力计算基本原理,推导电气-供热管网系统潮流修正方程及其雅可比矩阵元素表达式,提出计及电制热效率随系统运行环境变化的电热混合系统潮流静态分析方法。最后,通过算例分析验证了所提出方法的可行性及实用性。 展开更多
关键词 综合能源系统 平均温度响应 电锅炉 电制热效率 潮流计算 静态分析
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人工智能伦理研究的知识图谱分析 被引量:10
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作者 刘鸿宇 苗芳艳 +2 位作者 彭拾 夏思宇 王珏 《情报杂志》 CSSCI 北大核心 2019年第7期85-93,共9页
[目的/意义]随着人工智能技术的发展与应用,其衍生的伦理问题日益受到关注,但是国内从理论或技术层面防范人工智能伦理冲突的情报评述非常有限,收集人工智能伦理知识情报是当下人工智能健康发展的迫切需求。[方法/过程]借助CitespaceⅢ... [目的/意义]随着人工智能技术的发展与应用,其衍生的伦理问题日益受到关注,但是国内从理论或技术层面防范人工智能伦理冲突的情报评述非常有限,收集人工智能伦理知识情报是当下人工智能健康发展的迫切需求。[方法/过程]借助CitespaceⅢ对选自Web of Science的人工智能伦理领域文献进行知识图谱分析,分别利用检索式#1“人工智能伦理”主题文献与检索式#2“机器人伦理”主题文献进行全面且科学的知识聚类议题探析。[结果/结论]在聚类分析的基础上从人工智能载体的道德主体性研究、机器人的伦理价值敏感设计、人工道德智慧研究与人工智能技术的伦理控制四个方面对人工智能伦理研究领域进行了总结与展望。 展开更多
关键词 知识图谱 数据情报 人工智能伦理 机器人伦理
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血清PAD2、PCT及CRP对脓毒症的诊断价值 被引量:4
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作者 王历 彭适 +2 位作者 蔡馨 汤冬玲 张平安 《热带医学杂志》 CAS 2024年第9期1230-1234,I0004,共6页
目的探讨血清肽酰基精氨酸脱亚氨酶2(PAD2)、降钙素原(PCT)及C反应蛋白(CRP)对脓毒症的诊断价值。方法选择2022年1-12月武汉大学人民医院重症监护室收治的111例脓毒症患者(脓毒症组),50例非脓毒症患者(非脓毒症组),及同期48名健康体检者... 目的探讨血清肽酰基精氨酸脱亚氨酶2(PAD2)、降钙素原(PCT)及C反应蛋白(CRP)对脓毒症的诊断价值。方法选择2022年1-12月武汉大学人民医院重症监护室收治的111例脓毒症患者(脓毒症组),50例非脓毒症患者(非脓毒症组),及同期48名健康体检者(对照组)。酶联免疫吸附试验检测血清PAD2水平,自动化学发光免疫分析仪检测血清PCT水平,全自动蛋白分析仪检测CRP水平。比较3组PAD2、PCT、CRP水平差异,采用多因素logistic回归分析影响脓毒症的危险因素;Spearman相关性检验分析PAD2与PCT、CRP的相关性;受试者工作特征(ROC)曲线分析PAD2、PCT和CRP对脓毒症的诊断价值;Kappa一致性检验分析诊断准确性。结果脓毒症组血清PAD2、PCT及CRP水平[35.49(23.91,53.41)ng/mL、10.60(3.20,16.90)ng/mL、108.29(40.25,168.72)mg/L]高于非脓毒症组[22.52(12.89,33.64)ng/mL、2.85(1.58,4.46)ng/mL、33.99(15.38,58.09)mg/L]和对照组[9.83(7.33,15.22)ng/mL、0.04(0.04,0.06)ng/mL、3.00(3.00,3.00)mg/L],差异均有统计学意义(P均<0.05);且非脓毒症组PAD2、PCT及CRP水平高于对照组,差异均有统计学意义(P均<0.05)。PAD2、PCT、CRP水平升高是脓毒症发生的独立危险因素(P均<0.01)。血清PAD2水平与PCT、CRP成正相关(r=0.384、0.319,P均<0.001)。血清PAD2、PCT、CRP联合检测诊断脓毒症的曲线下面积(AUC)为0.955,均高于PAD2、PCT、CRP单独检测的0.845、0.882、0.870,差异均有统计学意义(Z=5.028、3.998、4.204,P均<0.001);且血清PAD2、PCT、CRP联合检测的kappa为0.779,均高于PAD2、PCT、CRP单独检测的0.521、0.611、0.576。结论脓毒症患者血清PAD2、PCT、CRP水平升高,是脓毒症发生的危险因素,三者联合诊断价值最高。 展开更多
关键词 脓毒症 肽酰基精氨酸脱亚氨酶2 降钙素原 C反应蛋白
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纤维蛋白原及血脂成分与冠心病患者PCI术后非罪犯血管病变进展的相关性分析 被引量:18
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作者 马茜钰 张金鹏 +3 位作者 张兆元 彭石 王姣 张锦 《解放军医学杂志》 CAS CSCD 北大核心 2021年第8期771-776,共6页
目的分析血浆纤维蛋白原(Fib)及血脂成分与冠心病患者经皮冠状动脉介入(PCI)术后非罪犯血管病变(NCCLs)进展的相关性。方法收集2017年1-12月在兰州大学第一医院心血管内科住院接受首次PCI治疗,并于2020年12月31日前复查冠状动脉造影(CAG... 目的分析血浆纤维蛋白原(Fib)及血脂成分与冠心病患者经皮冠状动脉介入(PCI)术后非罪犯血管病变(NCCLs)进展的相关性。方法收集2017年1-12月在兰州大学第一医院心血管内科住院接受首次PCI治疗,并于2020年12月31日前复查冠状动脉造影(CAG)的210例患者(两次手术至少间隔6个月以上)的临床资料进行回顾性分析。根据NCCLs是否进展分为进展组(n=99)和非进展组(n=111),同时根据进展组患者NCCLs进展程度再分为三个亚组:轻度进展组(n=42)、中度进展组(n=35)、重度进展组(n=22)。比较进展组和非进展组患者,轻、中、重度进展组患者的基线临床资料,分析Fib及血脂成分与NCCLs进展的相关性,以及影响NCCLs进展的危险因素。结果进展组与非进展组在性别、吸烟史、饮酒史、高血压史、高脂血症史、心力衰竭、入院血压方面差异无统计学意义(P>0.05),进展组平均年龄大于非进展组,且糖尿病患者多于非进展组,差异有统计学意义(P<0.05)。进展组血浆Fib、胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、非高密度脂蛋白胆固醇(non-HDL-C)水平高于非进展组,差异均有统计学意义(P<0.05);两组血浆三酰甘油(TG)、高密度脂蛋白胆固醇(HDL-C)水平差异无统计学意义(P>0.05)。随着NCCLs病变程度增加,血浆Fib、TG、LDL-C、non-HDL-C在轻、中、重度进展组中逐渐升高,而血浆HDL-C逐渐降低,但在各亚组间差异无统计学意义(P>0.05)。Fib、TC、LDL-C、non-HDL-C、D-二聚体与NCCLs进展呈正相关,且Fib与TC、LDL-C、non-HDL-C也呈正相关。性别、年龄、糖尿病史可作为NCCLs进展的危险因素,其OR值分别为2.284、1.052、0.293。结论血浆Fib及血脂成分与NCCLs进展相关,且Fib与部分血脂成分也存在相关性,但Fib不是NCCLs的危险因素。 展开更多
关键词 纤维蛋白原 血脂 冠状动脉 非罪犯血管病变 进展 相关性
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