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Microstructural evolution and mechanical properties of electron beam welded 5B70 aluminum alloy joint
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作者 Yu-peng ZHANG Guo JIN +9 位作者 Li-hong DONG Xiu-fang CUI Chong GAO Xiang-yu XIE Yue-lan DI Wei-ling GUO Ya-ya SONG Wen-jing SHI Ru-chuan ZENG Ning HUANG 《Transactions of Nonferrous Metals Society of China》 2026年第2期401-415,共15页
The microstructural evolution and mechanical properties of a vacuum electron beam welded aerospace 5B70 aluminum alloy joint were studied.Quantitative analyses of the phase composition,microstructural evolution,grain ... The microstructural evolution and mechanical properties of a vacuum electron beam welded aerospace 5B70 aluminum alloy joint were studied.Quantitative analyses of the phase composition,microstructural evolution,grain size,grain boundary density,and texture changes were performed by X-ray diffraction,scanning electron microscopy,and electron backscatter diffraction.The fusion zone(FZ)comprises equiaxed cellular crystals,and a fine~20μm-thick crystal layer forms in the transition zone(TZ)between the FZ and heat affected zone(HAZ).The HAZ closely resembles the base material(BM),retaining the original rolling microstructure.Mechanical property testing shows that the fine-grained layer in the TZ exhibits the highest nanohardness,with the FZ corresponding to the lowest microhardness.The welded-joint sample has lower yield strength,ultimate tensile strength,and elongation after fracture than the BM.These reductions of mechanical properties are primarily influenced by the grain size and distribution of the precipitated phases. 展开更多
关键词 5b70 aluminum alloy vacuum electron beam welding crystal structure nanohardness tensile properties
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Entropy regulation induced hollow prismatic structural NiCoFeInZnV-based layered double hydroxide with prominent electrochemical kinetics and stability for aqueous zinc-ion batteries
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作者 Liu Yang Tao Zou +9 位作者 Haihui Wu Jiqing Zhang Xuekun Sui Wenjing Zhang Ende Feng Xiaohui Guan Bao Liu Jingru Bai Penggang Yin Guangsheng Wang 《Journal of Energy Chemistry》 2026年第1期274-283,I0007,共11页
Layered double hydroxides(LDHs)hold great promise as cathode materials for aqueous zinc-ion batteries(AZIBs).Nevertheless,they also face challenges of sluggish kinetics and rapid capacity loss.Herein,a conformational ... Layered double hydroxides(LDHs)hold great promise as cathode materials for aqueous zinc-ion batteries(AZIBs).Nevertheless,they also face challenges of sluggish kinetics and rapid capacity loss.Herein,a conformational entropy regulation strategy has been applied to surmount the shortcomings.A medium-entropy iron-based metal organic framework(MIL-88)derived NiCoFeInZnV-based layered double hydroxide with carbon loaded(ME-NiCoFeInZnV-LDH/C)has been first proposed and prepared with a designed method.The increased entropy optimizes electron conductivity and alleviates structure alteration and diffusion barrier during interactions with charge carriers,due to electron-induced effect and“cocktail”effect.Moreover,the nanosheet assembled hollow prismatic structures could homogenize flux distribution and electric field distribution.Therefore,the electrochemical kinetics,crystal structure stability,and activity could be dramatically improved.Leveraging the advantages of structure and composition regulation,Zn||ME-NiCoFeInZnV-LDH/C zinc battery delivers high specific capacities,rate performance,and cycling stability.This work proposes a novel and feasible medium-entropy strategy to prepare a high-performance cathode for advanced AZIBs,which is of prominent significance for the development of charge storage devices. 展开更多
关键词 Medium-entropy strategy ME-NicoFeInZnV-LDH/c Nanosheet assembled hollow prismatic structures Aqueous zinc-ion batteries Improved electrochemical kinetics and activity
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Insights into the effect of Y substitution on superlattice structure and electrochemical performance of A_(5)B_(19)-type La-Mg-Ni-based hydrogen storage alloy for nickel metal hydride battery 被引量:6
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作者 Yanan Guo Wenfeng Wang +5 位作者 Huanhuan Su Hang Lu Yuan Li Qiuming Peng Shumin Han Lu Zhang 《Journal of Materials Science & Technology》 2025年第4期60-69,共10页
La-Mg-Ni-based hydrogen storage alloys with superlattice structures are the new generation anode material for nickel metal hydride(Ni-MH)batteries owing to the advantages of high capacity and exceptional activation pr... La-Mg-Ni-based hydrogen storage alloys with superlattice structures are the new generation anode material for nickel metal hydride(Ni-MH)batteries owing to the advantages of high capacity and exceptional activation properties.However,the cycling stability is not currently satisfactory enough which plagues its application.Herein,a strategy of partially substituting La with the Y element is proposed to boost the capacity durability of La-Mg-Ni-based alloys.Furthermore,phase structure regulation is implemented simultaneously to obtain the A5 B19-type alloy with good crystal stability specifically.It is found that Y promotes the phase formation of the Pr5 Co19-type phase after annealing at 985℃.The alloy containing Y contributes to the superior rate capability resulting from the promoted hydrogen diffusion rate.Notably,Y substitution enables strengthening the anti-pulverization ability of the alloy in terms of increasing the volume match between[A_(2)B_(4)]and[AB5]subunits,and effectively enhances the anti-corrosion ability of the alloy due to high electronegativity,realizing improved long-term cycling stability of the alloy from 74.2%to 78.5%after cycling 300 times.The work is expected to shed light on the composition and structure design of the La-Mg-Ni-based hydrogen storage alloy for Ni-MH batteries. 展开更多
关键词 Nickel metal hydride battery Y element La-Mg-Ni-based alloy A5 b19-type superlattice structure Electrochemical performance
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Comparative development and evaluation of Fe–N–C electrocatalysts for the oxygen reduction reaction:The effect of pyrolysis and iron-bipyridine structures
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作者 Georgios Charalampopoulos Maria K.Daletou 《Materials Reports(Energy)》 2025年第2期86-95,I0002,共11页
Proton exchange membrane fuel cells(PEMFCs)constitute a promising avenue for environmentally friendly power generation.However,the reliance on unsustainable platinum-based electrocatalysts used at the electrodes poses... Proton exchange membrane fuel cells(PEMFCs)constitute a promising avenue for environmentally friendly power generation.However,the reliance on unsustainable platinum-based electrocatalysts used at the electrodes poses challenges to the commercial viability of PEMFCs.Non-platinum group metal(non-PGM)alternatives,like nitrogen-coordinated transition metals in atomic dispersion(M–N–C catalysts),show significant potential.This work presents a comparative study of two distinct sets of Fe–N–C materials,prepared by pyrolyzing hybrid composites of polyaniline(PANI)and iron(Ⅱ)chloride on a hard template.One set uses bipyridine(BPy)as an additional nitrogen source and iron ligand,offering an innovative approach.The findings reveal that the choice of pyrolysis temperature and atmosphere influences the catalyst properties.The use of ammonia in pyrolysis emerges as a crucial parameter for promoting atomic dispersion of iron,as well as increasing surface area and porosity.The optimal catalyst,prepared using BPy and ammonia,exhibits a half-wave potential of 0.834 V in 0.5 M H_(2)SO_(4)(catalyst loading of 0.6 mg cm^(-2)),a mass activity exceeding 3 A g^(-1)and high stability in acidic electrolyte,positioning it as a promising non-PGM structure in the field. 展开更多
关键词 PEM fuel cells Oxygen reduction reaction Non-PGM electrocatalysts ORR activity Fe–N–c structures
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Refinement of core-shell hybrid structure reinforced CuZr-based bulk metallic glass matrix composites via dealloying in metallic melt
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作者 Wei GUO Long-feng LI +5 位作者 Zhen ZHANG Mi ZHAO Jin-cheng WANG Yan-qiang QIAO Shu-lin LÜ Shu-sen WU 《Transactions of Nonferrous Metals Society of China》 2025年第9期2988-2999,共12页
Metallic glass matrix composites(BMGCs)with compositions of[(Zr_(0.5)Cu_(0.5))_(0.925)Al_(0.07)Sn_(0.005)]_(100-x)Ta_(x)(atomic fraction,%,x=3,5,7)were successfully prepared via dealloying in metallic melt.The reinfor... Metallic glass matrix composites(BMGCs)with compositions of[(Zr_(0.5)Cu_(0.5))_(0.925)Al_(0.07)Sn_(0.005)]_(100-x)Ta_(x)(atomic fraction,%,x=3,5,7)were successfully prepared via dealloying in metallic melt.The reinforcing phase in these alloys has core-shell hybrid structure with Ta-rich particles as core and B2-CuZr as shell.In this method,the dealloyed Ta from Zr-Ta pre-alloys maintained in solid state and aggregated to form the fine Ta-rich phase in the final products.This effectively decreases the size of Ta-rich phase compared with that prepared via conventional arc-melting,where the Ta-rich phase was formed through dissolving and precipitation.Among the three compositions,[(Zr_(0.5)Cu_(0.5))_(0.925)Al_(0.07)Sn_(0.005)]_(95)Ta_(5) showed the highest plastic strain of 11.2%,much higher than that of the arc-melted counterparts(4.3%).Such improvement in mechanical properties was related with the refined core-shell hybrid reinforcing structure,which could hinder the rapid propagation of main shear band more efficiently and cause them to branch and proliferate at the interface. 展开更多
关键词 metallic glass matrix composites core-shell hybrid reinforcement structure dealloying in metallic melt strength and toughness b2-cuZr
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北斗三号MEO卫星B1C/B2a信号单系统精密产品性能评估
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作者 王乐 陆文龙 +3 位作者 解世超 冯瑞瑞 张奋 崔博斌 《测绘地理信息》 2026年第1期157-166,共10页
本文系统评估了北斗三号(BDS-3)MEO卫星B1C/B2a信号在单系统模式下的精密产品性能,从产品生成与应用两个层面,对比分析了BDS-3 MEO单系统与BDS-3MEO/GPS双系统的表现。结果显示:在定轨模糊度固定方面,BDS-3 MEO单系统的非差宽巷与窄巷... 本文系统评估了北斗三号(BDS-3)MEO卫星B1C/B2a信号在单系统模式下的精密产品性能,从产品生成与应用两个层面,对比分析了BDS-3 MEO单系统与BDS-3MEO/GPS双系统的表现。结果显示:在定轨模糊度固定方面,BDS-3 MEO单系统的非差宽巷与窄巷固定率分别为97.97%和90.28%,接近双系统水平;单系统轨道的1D RMS为51.2 mm,略低于双系统,而钟差拟合残差平均值为0.14 ns,序列平滑性优于双系统;在地球自转参数(ERP)方面,X、Y极坐标的RMS分别为39.2μas和27.8μas,X、Y极坐标速率的RMS分别为230.0μas/d和262.2μas/d,日长变化的RMS为203.2μs/d,部分指标略低于双系统,但整体仍满足精密产品要求;单系统天顶总延迟(ZTD)的平均RMSE为6.7 mm;单系统网解PPP的非差模糊度宽巷固定率超过98%,窄巷平均固定率为83%;静态精密单点定位(PPP)中,单系统收敛时间为27.89 min,E、N、U三个方向的精度分别为1.71 cm、2.34 cm和1.25 cm;在框架一致性比对中,单系统的平均尺度变化为0.065 ppb,优于双系统的0.188 ppb,表明在BDS天线对齐至ITRF 2020后单系统产品框架一致性表现良好。研究证实,BDS-3单系统具备独立生成高精度产品的能力,为北斗系统实现自主运行提供了有力支撑。 展开更多
关键词 北斗三号 MEO b1c/b2a 单系统性能评估
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Structures and electrochemical hydrogen storage performance of Si added A_2B_7-type alloy electrodes 被引量:6
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作者 张羊换 任慧平 +3 位作者 蔡颖 杨泰 张国芳 赵栋梁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期406-414,共9页
In order to ameliorate the electrochemical hydrogen storage performance of La-Mg-Ni system A2B7-type electrode alloys, a small amount of Si was added. The La0.8Mg0.2Ni3.3Co0.2Six (x=0-0.2) electrode alloys were prep... In order to ameliorate the electrochemical hydrogen storage performance of La-Mg-Ni system A2B7-type electrode alloys, a small amount of Si was added. The La0.8Mg0.2Ni3.3Co0.2Six (x=0-0.2) electrode alloys were prepared by casting and annealing. The effects of adding Si on the structure and electrochemical hydrogen storage characteristics of the alloys were investigated systematically. The results indicate that the as-cast and annealed alloys hold multiple structures, involving two major phases of (La, Mg)2Ni7 with a Ce2Ni7-type hexagonal structure and LaNi5 with a CaCu5-type hexagonal structure as well as one residual phase LaNi3. The addition of Si results in a decrease in (La, Mg)2Ni7 phase and an increase in LaNi5 phase without changing the phase structure of the alloys. What is more, it brings on an obvious effect on electrochemical hydrogen storage characteristics of the alloys. The discharge capacities of the as-cast and annealed alloys decline with the increase of Si content, but their cycle stabilities clearly grow under the same condition. Furthermore, the measurements of the high rate discharge ability, the limiting current density, hydrogen diffusion coefficient as well as electrochemical impedance spectra all indicate that the electrochemical kinetic properties of the electrode alloys first increase and then decrease with the rising of Si content. 展开更多
关键词 A2b7-type electrode alloy Si additive structure electrochemical characteristics
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银杏内酯B经PERK/ATF4/CHOP通路调控肝癌细胞增殖、迁移、凋亡和EMT
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作者 刘燕华 王红娟 +6 位作者 鲍柏军 朱隽雅 易楠 纪易婓 黄伟 张莉 刘国良 《中国肿瘤生物治疗杂志》 北大核心 2026年第1期51-58,共8页
目的:探究银杏内酯B(GKB)调控蛋白激酶R样内质网激酶(PERK)/转录激活子4(ATF4)/C/EBP同源蛋白(CHOP)信号通路对肝癌细胞增殖、迁移、凋亡和上皮间质转化(EMT)的影响。方法:将人肝癌细胞MHCC-97H随机分为对照组、GKB组、GSK2656157(PERK... 目的:探究银杏内酯B(GKB)调控蛋白激酶R样内质网激酶(PERK)/转录激活子4(ATF4)/C/EBP同源蛋白(CHOP)信号通路对肝癌细胞增殖、迁移、凋亡和上皮间质转化(EMT)的影响。方法:将人肝癌细胞MHCC-97H随机分为对照组、GKB组、GSK2656157(PERK抑制剂)组和GKB+GSK2656157组,以GKB和GSK2656157分别干预后,采用MTT法和EdU染色检测各组细胞的增殖活性及增殖率,划痕愈合实验、流式细胞术分别检测各组细胞的迁移及凋亡水平,WB法检测各组细胞中EMT和PERK/ATF4/CHOP信号通路相关蛋白的表达水平。构建MHCC-97H细胞裸鼠移植瘤模型,以同法分组及药物干预后测定各组移植瘤体积,采用免疫组化、TUNEL染色分别检测各组肿瘤细胞增殖、凋亡水平,WB法检测各组移植瘤组织中EMT和PERK/ATF4/CHOP信号通路相关蛋白的表达水平。结果:与对照组比较,GKB组细胞活性、增殖率、迁移率、移植瘤体积、Ki-67阳性细胞率、MMP2、N-cadherin与MMP9蛋白表达均显著降低(均P<0.05),细胞凋亡率、TUNEL阳性细胞率、p-PERK/PERK与E-cadherin、ATF4、CHOP蛋白表达均显著升高(均P<0.05);GSK2656157组各指标变化与GKB组相反(均P<0.05)。与GKB组比较,GKB+GSK2656157组细胞活性、增殖率、迁移率、移植瘤体积、Ki-67阳性细胞率、MMP2、N-cadherin与MMP9蛋白表达均显著升高(均P<0.05),细胞凋亡率、TUNEL阳性细胞率、p-PERK/PERK与E-cadherin、ATF4、CHOP蛋白表达均显著降低(均P<0.05)。结论:GKB可通过激活PERK/ATF4/CHOP信号通路抑制肝癌MHCC-97H细胞增殖、迁移和EMT并促进其凋亡。 展开更多
关键词 银杏内酯b 蛋白激酶R样内质网激酶/转录激活子4/c/EbP同源蛋白通路 肝癌 增殖 迁移 凋亡 上皮间质转化
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元素掺杂及分子吸附对B4C3电子性质的影响
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作者 李萱 邵立 +2 位作者 门彩瑞 何渊淘 李艳 《吉林大学学报(理学版)》 北大核心 2026年第1期158-165,共8页
研究S,N,P,Si 4种原子掺杂和NO,NO_(2),NH_(3),CO,CO_(2),SO_(2),H_(2)S 7种小分子吸附对B_(4)C_(3)二维材料几何结构和电子性质的影响.结果表明,与本征B_(4)C_(3)材料2.020 eV带隙相比,掺杂和小分子吸附体系的禁带宽度均减小.其中,N掺... 研究S,N,P,Si 4种原子掺杂和NO,NO_(2),NH_(3),CO,CO_(2),SO_(2),H_(2)S 7种小分子吸附对B_(4)C_(3)二维材料几何结构和电子性质的影响.结果表明,与本征B_(4)C_(3)材料2.020 eV带隙相比,掺杂和小分子吸附体系的禁带宽度均减小.其中,N掺杂体系的带隙值在4种体系中最小,因此掺杂N原子对B_(4)C_(3)的电子性质影响最明显. NO_(2)吸附后B_(4)C_(3)由半导体变为金属,表明B_(4)C_(3)可有效检测NO_(2)气体. 展开更多
关键词 密度泛函理论 二维b4c3 掺杂 吸附
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Computational analysis of genetic loci required for amphid structure and functions and their possibly corresponding microRNAs in C. elegans 被引量:1
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作者 胡亚欧 孙阳 +1 位作者 叶波平 王大勇 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第1期9-20,共12页
Objective To examine the important roles of microRNAs (miRNAs) in regulating amphid structure and function, we performed a computational analysis for the genetic loci required for the sensory perception and their po... Objective To examine the important roles of microRNAs (miRNAs) in regulating amphid structure and function, we performed a computational analysis for the genetic loci required for the sensory perception and their possibly corresponding miRNAs in C. elegans. Methods Total 55 genetic loci required for the amphid structure and function were selected. Sequence alignment was combined with E value evaluation to investigate and identify the possible corresponding miRNAs. Results Total 30 genes among the 55 genetic loci selected have their possible corresponding regulatory miRNA(s), and identified genes participate in the regulation of almost all aspects of amphid structure and function. In addition, our data suggest that both the amphid structure and the amphid functions might be regulated by a series of network signaling pathways. Moreover, the distribution of miRNAs along the 3' untranslated region (UTR) of these 30 genes exhibits different patterns. Conclusion We present the possible miRNA-mediated signaling pathways involved in the regulation of chemosensation and thermosensation by controlling the corresponding sensory neuron and interneuron functions. Our work will be useful for better understanding of the miRNA-mediated control of the chemotaxis and thermotaxis in C. elegans. 展开更多
关键词 microRNA cilia structure sensory neuron INTERNEURON computational analysis c. elegans
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DAAs治疗HCV感染发生HBV再激活的风险:系统评价及Meta分析
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作者 陈莹 陈君 +5 位作者 钟韵 成苇婷 刘泽颖 杨雪瑶 李雪璇 黄泽炳 《中国感染控制杂志》 北大核心 2026年第1期32-46,共15页
目的比较接受直接抗病毒药物(DAAs)治疗的丙型肝炎病毒(HCV)感染患者乙型肝炎病毒(HBV)再激活风险,并评估抗HBV治疗预防HBV再激活的有效性。方法计算机检索中国知网(CNKI)、万方数据库、PubMed、Embase、Cochrane Library数据库,纳入自... 目的比较接受直接抗病毒药物(DAAs)治疗的丙型肝炎病毒(HCV)感染患者乙型肝炎病毒(HBV)再激活风险,并评估抗HBV治疗预防HBV再激活的有效性。方法计算机检索中国知网(CNKI)、万方数据库、PubMed、Embase、Cochrane Library数据库,纳入自建库至2025年2月13日发表的相关文献。按预设纳入与排除标准筛选文献,提取资料并评估质量。采用Revman 5.4和Stata 18.0软件进行Meta分析,并开展敏感性分析和发表偏倚评估。结果共纳入32篇文献,包括31篇队列研究和1篇随机对照研究。涉及21530例HCV感染患者。27项研究报告HCV感染合并HBsAg阳性患者DAAs治疗后的合并HBV再激活发生率为30%(95%CI:16%~45%),24项研究报告HCV感染合并HBsAg阴性、HBcAb阳性患者合并HBV再激活率为0,各研究报道的再激活发生率范围为0~15%。选取14篇文献比较HCV感染合并HBsAg阳性与HCV感染合并HBsAg阴性、HBcAb阳性患者DAAs治疗后HBV再激活的风险,相对危险度(RR)=31.06(95%CI:17.98~53.65)。HCV感染合并HBsAg阳性患者中,HBV DNA<检测下限(LLOQ)组与HBV DNA≥LLOQ组的HBV再激活风险差异无统计学意义(RR=0.75,95%CI:0.52~1.06)。HCV感染合并HBsAg阳性患者中,DAAs治疗同时使用核苷(酸)类似物(NAs)进行预防性抗HBV治疗者,其HBV再激活风险仅为对照组的19%(RR=0.19,95%CI:0.06~0.58)。结论HCV感染合并HBsAg阳性患者接受DAAs治疗后HBV再激活发生率较高;HCV感染合并HBsAg阴性、HBcAb阳性患者接受DAAs治疗后基于现有数据合并HBV再激活发生率估计值为0,但仍存在个别再激活报告,风险并未完全排除。使用NAs预防性抗HBV治疗可降低HCV感染合并HBsAg阳性患者DAAs治疗的HBV再激活风险。对HCV感染患者实施预防性抗HBV治疗和持续管理,有助于提高DAAs治疗的安全性并优化整体疗效。 展开更多
关键词 丙型肝炎病毒 直接抗病毒药物 乙型肝炎病毒再激活
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1例ABO血型系统B^(*)等位基因c.28G>A突变致B抗原减弱的遗传学分析
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作者 王雅茹 任晓艳 +2 位作者 蔡忠鹤 李萌 何婷 《南京医科大学学报(自然科学版)》 北大核心 2026年第2期309-314,共6页
ABO血型系统是人类最重要的血型系统之一,其精准鉴定是临床安全输血的基石。常规血清学检测中,由于ABO抗原表达减弱或缺失导致的正反定型不符,是输血科工作面临的重要挑战。血型基因分型及测序技术的飞速发展,克服了血清学方法依赖抗原... ABO血型系统是人类最重要的血型系统之一,其精准鉴定是临床安全输血的基石。常规血清学检测中,由于ABO抗原表达减弱或缺失导致的正反定型不符,是输血科工作面临的重要挑战。血型基因分型及测序技术的飞速发展,克服了血清学方法依赖抗原-抗体反应的局限性,为临床输血安全提供了更坚实的保障。 展开更多
关键词 AbO血型系统 b抗原弱表达 c.28G>A突变 家系分析 生物信息学分析
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超高温淬火对新型Fe-Cr-B-C合金硬度、冲击韧性和耐磨性能的影响
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作者 韩思莹 赵广迪 +5 位作者 于镇铭 杜磊 王茜雯心 于江铖 王楚今 周艳文 《材料热处理学报》 北大核心 2026年第1期96-107,共12页
Fe-Cr-B-C合金是一种低成本的高硼铁基耐磨合金,具有广阔的应用前景。研究了超高温淬火对一种成分优化的(B含量为0.51 mass%)Fe-Cr-B-C合金显微组织、硬度、冲击韧性和耐磨性能的影响。结果表明:当淬火温度为1100℃,合金基体内析出大量... Fe-Cr-B-C合金是一种低成本的高硼铁基耐磨合金,具有广阔的应用前景。研究了超高温淬火对一种成分优化的(B含量为0.51 mass%)Fe-Cr-B-C合金显微组织、硬度、冲击韧性和耐磨性能的影响。结果表明:当淬火温度为1100℃,合金基体内析出大量二次硼碳化物,降低了马氏体的过饱和度,同时形成了细小的新晶粒,原始网状硼碳化物发生局部断网,这导致其洛氏硬度最低,冲击吸收能量较高,耐磨性能最差;随着淬火温度升高至1160℃,不再析出二次硼碳化物,也不再形成新晶粒,硼碳化物的断网现象更加明显,而马氏体过饱和度不断增大,这导致洛氏硬度增大至(63.2±0.8) HRC,耐磨性能提高;当淬火温度继续升高至1190℃时,重新析出了大量[γ+(Fe, Cr)_(2)(B, C)]共晶组织并形成网状结构,导致洛氏硬度小幅下降,冲击韧性恶化,耐磨性能明显下降;合金的冲击吸收能量随淬火温度的升高先增大后减小,当淬火温度为1130℃时达到最大,为(4.25±0.25) J;综合来看,经1160℃淬火后Fe-Cr-B-C合金获得了良好的强韧性匹配和优异的耐磨性能,可作为其优选淬火温度。 展开更多
关键词 Fe-cr-b-c合金 超高温淬火 硬度 冲击韧性 耐磨性
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TSH、ApoA/ApoB及CRP与慢性阻塞性肺疾病并发静脉血栓栓塞症的相关性研究
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作者 韩盼盼 彭威 曾曼 《临床研究》 2026年第2期147-150,共4页
目的观察促甲状腺激素(TSH)、载脂蛋白A(ApoA)/载脂蛋白B(ApoB)及C反应蛋白(CRP)与慢性阻塞性肺疾病(COPD)并发静脉血栓栓塞症(VTE)的相关性。方法采用回顾性研究方法,选择2018年3月至2023年3月虞城县人民医院收治的COPD并发VTE患者100... 目的观察促甲状腺激素(TSH)、载脂蛋白A(ApoA)/载脂蛋白B(ApoB)及C反应蛋白(CRP)与慢性阻塞性肺疾病(COPD)并发静脉血栓栓塞症(VTE)的相关性。方法采用回顾性研究方法,选择2018年3月至2023年3月虞城县人民医院收治的COPD并发VTE患者100例为观察组,同期未发生VTE的COPD患者108例为对照组。比较两组实验室指标[D-二聚体、CRP、ApoA/ApoB、降钙素原(PCT)、血尿素氮、血肌酐、白蛋白]、甲状腺功能指标[促甲状腺激素(TSH)、三碘甲状腺原氨酸(T_(3))、游离三碘甲状腺原氨酸(FT_(3))、甲状腺素(T_(4))、游离甲状腺素(FT_(4))]、动脉血气指标[动脉血二氧化碳分压(PaCO_(2))、动脉血氧分压(PaO_(2))],采用二元Logistic回归分析COPD并发VTE的相关因素。结果观察组D-二聚体、CRP水平及PaCO_(2)高于对照组,ApoA/ApoB比值、PaO_(2)及TSH、T_(3)、FT_(3)水平低于对照组,差异有统计学意义(P<0.05)。二元Logistic回归分析结果显示,D-二聚体、CRP和PaCO_(2)水平的升高是COPD并发VTE的独立危险因素(P<0.05);而ApoA/ApoB比值、TSH、T_(3)、FT_(3)和PaO_(2)水平的升高是保护因素(P<0.05)。结论COPD并发VTE患者表现出TSH水平和ApoA/ApoB比值降低、CRP水平升高的特征性改变,这些改变与COPD并发VTE密切相关。 展开更多
关键词 慢性阻塞性肺疾病 静脉血栓栓塞症 促甲状腺激素 载脂蛋白A/载脂蛋白b c反应蛋白 相关性
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B2B2C模式下企业采购EAP服务的决策机制与营销策略
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作者 尚静 《物流科技》 2026年第2期33-36,共4页
研究聚焦B2B2C商业模式下企业采购EAP服务的决策机制与营销策略这一新兴研究领域。基于决策理论与服务营销理论,构建了“需求-决策-营销”整合分析框架,系统考察了EAP服务采购的全过程。研究发现:企业采购决策呈现多维度特征,经济与非... 研究聚焦B2B2C商业模式下企业采购EAP服务的决策机制与营销策略这一新兴研究领域。基于决策理论与服务营销理论,构建了“需求-决策-营销”整合分析框架,系统考察了EAP服务采购的全过程。研究发现:企业采购决策呈现多维度特征,经济与非经济因素共同影响采购行为,且决策过程中存在显著的信息不对称问题;在营销策略方面,EAP服务提供商需实施精准市场细分、定制化价值传递以及多渠道整合传播的三维策略体系。 展开更多
关键词 b2b2c模式 EAP 决策机制 营销策略
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Physics-informed machine learning for identifying gradient-distributed plastic parameters of the S38C axle by nano-indentation
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作者 Siyu Li Lvfeng Jiang +4 位作者 Yanan Hu Jian Li Xu Zhang Qianhua Kan Guozheng Kang 《Acta Mechanica Sinica》 2026年第1期105-121,共17页
The S38C railway axle undergoes induction hardening,resulting in a gradient-distributed microstructure and mechanical properties.The accurate identification of gradient-distributed plastic parameters for the S38C axle... The S38C railway axle undergoes induction hardening,resulting in a gradient-distributed microstructure and mechanical properties.The accurate identification of gradient-distributed plastic parameters for the S38C axle remains a challenging task.To tackle this challenge,the present study proposes a novel approach for identifying the gradient-distributed plastic parameters for the S38C axle by integrating nano-indentation techniques with the machine learning method.Firstly,nano-indentation tests are conducted along the radial direction of the S38C axle to obtain the gradient-distributed load-displacement curves,nano-hardness,and elastic modulus.Subsequently,the dimensionless analysis is performed to obtain the representative stress,strain,and yield stress from load-displacement curves.These parameters are then incorporated into the machine learning method as physical information to identify the gradient-distributed plastic parameters of the S38C axle.The results indicate that the proposed method based on the physics-informed neural network and multi-fidelity neural network successfully identifies the gradient-distributed plastic parameters of the S38C axles and demonstrates superior prediction accuracy and generalization compared with the purely data-driven machine learning method. 展开更多
关键词 S38c axle Nanoindentation Physics-informed machine learning Gradient structure Plastic parameters
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Integrative Multi-Omics Analysis and Experiments Validation Identify COX5B as a Novel Therapeutic Target for Lung Adenocarcinoma
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作者 Lv Ling Minying Lu +5 位作者 Ling Ye Yuanhang Chen Sheng Lin Jun Yang Yu Rong Guixiong Wu 《Oncology Research》 2026年第1期479-499,共21页
Background:A significant proportion of patients still cannot benefit from existing targeted therapies and immunotherapies,making the search for new treatment strategies extremely urgent.In this study,we combined integ... Background:A significant proportion of patients still cannot benefit from existing targeted therapies and immunotherapies,making the search for new treatment strategies extremely urgent.In this study,we combined integrate public data analysis with experimental validation to identify novel prognostic biomarkers and therapeutic targets for lung adenocarcinoma(LUAD).Methods:We analyzed RNA and protein databases to assess the expression levels of cytochrome C oxidase 5B(COX5B)in LUAD.Several computational algorithms were employed to investigate the relationship between COX5B and immune infiltration in LUAD.To further elucidate the role of COX5B in LUAD,we utilized multiple experimental approaches,including quantitative reverse transcription PCR assays,western blot,immunohistochemistry,electron microscopy,flow cytometry,and EdU proliferation assays.Results:We revealed that COX5B was significantly elevated in LUAD and positively correlated with poor prognosis of LUAD patients.Analysis of co-expression network indicated that COX5B may take part in the intracellular adenosine triphosphate(ATP)synthesis through the oxidative phosphorylation pathway.There was a negative correlation between COX5B expression and immune infiltration in LUAD.Furthermore,we validated that COX5B levels were significantly elevated in both LUAD tissues and cell lines.Specifically,immunohistochemistry(IHC)assays revealed a 2.32-fold increase of COX5B in tumor tissues compared to that in adjacent normal tissues(p=0.0044).Additionally,COX5B knockdown disrupted the redox homeostasis,ultimately suppressed the proliferation of LUAD cells.Subsequent investigations demonstrated that berberine effectively targeted COX5B,diminishing its protein expression and consequently inhibiting cell proliferation and tumor growth in LUAD.Conclusions:This study established that upregulated COX5B was positive associated with poor patient prognosis in LUAD,elucidating the mechanisms by which berberine targets COX5B to inhibit tumor growth,thereby providing a novel therapeutic target and strategy for the clinical management of LUAD. 展开更多
关键词 Lung adenocarcinoma(LUAD) cytochrome c oxidase 5b(cOX5b) prognosis PROLIFERATION bERbERINE
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Molecular phylogeography and population history of Saccostrea mordax based on mitochondrial DNA
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作者 Zeyu TANG Cui LI +3 位作者 Guochen ZANG Zhenqiang LIU Zongmei CUI Haiyan WANG 《Journal of Oceanology and Limnology》 2026年第1期357-371,共15页
The Saccostrea mordax Gould,1850 is a typical intertidal species,whose genetic differentiation is influenced by various factors,including geological and climatic changes.To explore the genetic structure and historical... The Saccostrea mordax Gould,1850 is a typical intertidal species,whose genetic differentiation is influenced by various factors,including geological and climatic changes.To explore the genetic structure and historical population characteristics of Saccostrea mordax,we sequenced the mitochondrial cytochrome c oxidase subunit I(COI)gene from 58 specimens sampled from four locations in the western Pacific.Additionally,103 individuals from the Persian Gulf and western Pacific(from databases)were included for phylogenetic analysis.The Bayesian Inference tree showed that all specimens were divided into two clades,i.e.,the Persian Gulf population and the western Pacific population.Spatial molecular variance analysis indicated significant genetic differentiation between the two populations,and isolation by distance analysis revealed a positive correlation between genetic differentiation and geographic distance.Neutrality tests and Bayesian Skyline Plot suggested that both populations underwent expansions during the late Pleistocene.This study revealed the population history of Saccostrea mordax and described a new lineage,Saccostrea mordax lineage D,providing a foundation for understanding oyster biodiversity formation and genetic resource conservation. 展开更多
关键词 Saccostrea mordax cytochrome c oxidase subunit I(cOI) genetic structure population expansion Saccostrea mordax lineage D
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活化蛋白C、血栓素B2对妊娠合并抗磷脂综合征妊娠结局的预测价值
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作者 冯蓉 孙珊珊 《国际检验医学杂志》 2026年第3期337-341,347,共6页
目的探讨活化蛋白C(APC)、血栓素B2(TXB2)对妊娠合并抗磷脂综合征(APS)妊娠结局的预测价值。方法选取2022年1月至2024年12月在该院就诊的204例APS孕妇为研究对象,根据妊娠结局将其分为妊娠不良组(104例)和妊娠良好组(100例)。检测各组血... 目的探讨活化蛋白C(APC)、血栓素B2(TXB2)对妊娠合并抗磷脂综合征(APS)妊娠结局的预测价值。方法选取2022年1月至2024年12月在该院就诊的204例APS孕妇为研究对象,根据妊娠结局将其分为妊娠不良组(104例)和妊娠良好组(100例)。检测各组血浆APC、TXB2水平,绘制受试者工作特征(ROC)曲线评价血浆APC、TXB2对APS孕妇妊娠结局的预测价值,采用二分类Logistic逐步回归分析APS孕妇妊娠结局的影响因素。结果与妊娠良好组比较,妊娠不良组血浆APC水平降低(P<0.05),血浆TXB2水平升高(P<0.05)。血浆APC、TXB2及二者联合预测APS孕妇妊娠结局的曲线下面积(AUC)及95%CI分别为0.726(0.681~0.776)、0.839(0.794~0.889)、0.902(0.857~0.952),血浆APC、TXB2二者联合预测APS孕妇妊娠结局的AUC大于二者单独预测的AUC(Z=9.207、11.365,P<0.05)。妊娠不良组未使用低剂量阿司匹林(LDA)联合低分子肝素(LMWH)、既往不良孕产史、既往血栓史的人数占比均高于妊娠良好组(P<0.05)。二分类Logistic逐步回归分析显示,未使用LDA联合LMWH治疗(OR=2.115,95%CI 1.134~3.944),既往不良孕产史(OR=2.307,95%CI 1.372~3.878),血浆APC≤8.38ng/mL(OR=3.607,95%CI1.900~6.848),血浆TXB2≥253.36pg/mL(OR=3.019,95%CI 1.835~4.967)是影响APS孕妇不良妊娠结局的独立危险因素(P<0.05)。结论血浆APC水平降低、TXB2水平升高与妊娠合并APS患者的不良妊娠结局密切相关,二者联合检测对其不良妊娠结局具有较高的预测价值。 展开更多
关键词 抗磷脂综合征 妊娠结局 活化蛋白c 血栓素b2
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Synthesis of porous nano/micro structured LiFePO_4/C cathode materials for lithium-ion batteries by spray-drying method 被引量:2
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作者 管晓梅 李国军 +1 位作者 黎春阳 任瑞铭 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第1期141-147,共7页
In order to enhance electrochemical properties of LiFePO4 (LFP) cathode materials, spherical porous nano/micro structured LFP/C cathode materials were synthesized by spray drying, followed by calcination. The result... In order to enhance electrochemical properties of LiFePO4 (LFP) cathode materials, spherical porous nano/micro structured LFP/C cathode materials were synthesized by spray drying, followed by calcination. The results show that the spherical precursors with the sizes of 0.5-5 μm can be completely converted to LFP/C when the calcination temperature is higher than 500 ℃. The LFP/C microspheres obtained at calcination temperature of 700 ℃ are composed of numerous particles with sizes of -20 nm, and have well-developed interconnected pore structure and large specific surface area of 28.77 mE/g. The specific discharge capacities of the LFP/C obtained at 700 ℃ are 162.43, 154.35 and 144.03 mA.h/g at 0.5C, 1C and 2C, respectively. Meanwhile, the capacity retentions can reach up to 100% after 50 cycles. The improved electrochemical properties of the materials are ascribed to a small Li+ diffusion resistance and special structure of LFP/C microspheres. 展开更多
关键词 LiFePO4/c cathode nano/micro structure porous material spray drying electrochemical properties
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