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Ni、Zr对Al-Si-Cu-Mg合金组织与高温力学性能的影响

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特种铸造及有色合金 2024年第3期44卷 419-423页

作者：路通邱楚张跃波薛冠霞宋炜刘涛李虎田中铝材料应用研究院有限公司苏州分公司苏州215026 中铝材料应用研究院有限公司北京102209

利用金属型铸造开展了Al-Si-Cu-Mg过共晶活塞合金的制备,通过Thermo-Calc软件对不同合金中耐热相的体积分数进行计算,结合扫描电镜(SEM)和透射电镜(TEM)对合金的组织进行定量金相分析,同时对合金在350℃下的力学性能进行测试,研究了不... 详细信息

利用金属型铸造开展了Al-Si-Cu-Mg过共晶活塞合金的制备,通过Thermo-Calc软件对不同合金中耐热相的体积分数进行计算,结合扫描电镜(SEM)和透射电镜(TEM)对合金的组织进行定量金相分析,同时对合金在350℃下的力学性能进行测试,研究了不同Ni和Zr含量对铸造Al-Si-Cu-Mg基过共晶活塞合金显微组织和力学性能的影响,分析了金属间化合物形貌和面积分数与力学性能的对应关系。结果表明,随着Ni含量增加,Al-12.5Si-4.0Cu-1.0Mg合金在350℃下的抗拉强度和屈服强度逐渐增加,伸长率逐渐降低,组织中的Al_(3)Ni和Al_(3)CuNi相的数量增多,并且形貌由针状和棒状逐步演变成块状和团簇状,耐热相面积分数也有明显增加;随着Zr含量增加,Al-12.5Si-4Cu-1.0Mg-1.5Ni合金的抗拉强度和屈服强度先降低后升高,伸长率逐渐增大,组织中的AlSiNiZr相数量逐渐增多,并且耐热相面积分数逐渐增大。Al_(3)Zr沿着铝基体[001]轴析出,并且与铝基体共格,形成高温强化相,通过强化铝基体提高了合金的高温强度。

关键词：过共晶活塞合金耐热相显微组织力学性能

Compact Ceshro Operators from Spaces H（p,q,u） to H（p, q, v）

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Acta Mathematicae Applicatae Sinica 2006年第3期22卷 437-442页

作者： xue-jun Zhang Yu-ming chu College of Mathematics and Computer Science Hunan Normal University Changsha 410006 China Department of Mathematics Huzhou Teachers College Huzhou 313000 China

Let μ and v be normal functions and let Tg be the extended Ceshso operator in terms of the symbol g. In this paper, we will characterize those g so that Tg is bounded （or compact） from mixed norm spaces H（p, q, μ） to H（p, q, v） in the unit ball of C^n, Furthermore, as applications, some analogous results are also given on weighted Bergman spaces and Dirichlet type spaces.

关键词： Cesàro operator boundedness compactness mixed norm space

锑锡氧化物掺杂碳纳米管导电膜的制备及电氧化性能研究

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山东化工 2024年第13期53卷 1-7页

作者：张静怡孟雪宁月婷初永宝青岛科技大学环境与安全工程学院山东青岛266042 青岛科技大学高分子科学与工程学院山东青岛266042

塑料添加剂双酚A(BPA)作为典型激素/干扰内分泌的化学物质(EDCs)在环境中无处不在,为实现BPA的高效去除,采用抽滤的方式制备了锑锡氧化物掺杂碳纳米管的导电膜(SnO_(2)-Sb@CNTEM),并通过膜过滤和电氧化过程的耦合去除BPA。通过SEM、XPS... 详细信息

塑料添加剂双酚A(BPA)作为典型激素/干扰内分泌的化学物质(EDCs)在环境中无处不在,为实现BPA的高效去除,采用抽滤的方式制备了锑锡氧化物掺杂碳纳米管的导电膜(SnO_(2)-Sb@CNTEM),并通过膜过滤和电氧化过程的耦合去除BPA。通过SEM、XPS、XRD对膜电极的表面性质进行了表征,并通过LSV、CV、EIS对SnO_(2)-Sb@CNTEM的电化学性质进行了表征。以BPA为目标污染物,考察了膜电极的电氧化性能、稳定性,以SMX、DCF、CIP、TC为目标污染物,考察了膜电极的通用性。研究表明,成功制备了SnO_(2)-Sb@CNTEM;SnO_(2)-Sb@CNTEM的电氧化性能优于CNTEM;BPA在本研究条件下更容易被降解;SnO_(2)-Sb@CNTEM具有较高的稳定性和通用性。

关键词：锑锡氧化物掺杂碳纳米管导电膜电催化氧化双酚A 降解

Anti-Phase Relationship Between the East Asian Winter Monsoon and Summer Monsoon During the Holocene?

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Journal of Ocean University of China 2017年第2期16卷 175-183页

作者： GE Qian xue Zuo YAO Zhigang ZANG Zhengchen chu Fengyou Second Institute of Oceanography State Oceanic AdministrationHangzhou 310012P.R.China Key Laboratory of Submarine Geosciences State Oceanic AdministrationHangzhou 310012P.R.China Department of Oceanography and Coastal Sciences Louisiana State UniversityBaton RougeLA 70803USA Center for Computation and Technology Louisiana State UniversityBaton RougeLA 70803USA Coastal Studies Institute Louisiana State UniversityBaton RougeLA 70803USA Key Laboratory of Physical Oceanography Ocean University of ChinaQingdao 266100P.R.China

The relationship between the East Asian winter monsoon(EAWM) and East Asian summer monsoon(EASM) during the Holocene is complicated and remains *** this study,analysis of grain size and benthic foraminiferal oxygen isotope,as well as accelerator mass spectrometry ^(14)C dating was performed on a sediment core retrieved from the newly revealed muddy deposit on the northern South China Sea continental *** history of the EAWM and EASM were reconstructed for the last 8200 a *** analysis in conjunction with previously published paleo-climate proxies revealed that the relationship between the EAWM and EASM during the Holocene is more complex than a simple and strict anti-phase one-both negative and positive correlations were *** EAWM and EASM are negatively correlated around 7500,4800,4200,3200,and 300 a BP(cooling periods),while positively correlated around 7100,3700,and 2100 a BP(warm periods).In particular,both the EAWM and EASM intensified during the three positive correlation ***,we also found that the relationship between these two sub-monsoons is anti-phase during the final phase of particularly hot periods like Holocene Optimum and Medieval warm *** possible impact from variations of solar irradiance on the relationship between the EAWM and EASM was also discussed.

关键词： grain size oxygen isotope South China Sea East Asian winter monsoon East Asian summer monsoon Holocene

呼吸窘迫综合征新生患儿血浆中miRNAs的差异性表达及临床意义

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新疆医科大学学报 2024年第3期47卷 372-377页

作者：张桓褚瑞海薛琦路真潍坊医学院山东潍坊261000 潍坊市人民医院感染科山东潍坊261000

目的探讨呼吸窘迫综合征(Respiratory distress syndrome, RDS)新生患儿血浆miRNAs的差异表达及意义。方法选取68例RDS新生患儿、15例健康新生儿为研究对象,随机各选取6例进行血浆测序,用反转录聚合酶链反应(Reverse transcription-po... 详细信息

目的探讨呼吸窘迫综合征(Respiratory distress syndrome, RDS)新生患儿血浆miRNAs的差异表达及意义。方法选取68例RDS新生患儿、15例健康新生儿为研究对象,随机各选取6例进行血浆测序,用反转录聚合酶链反应(Reverse transcription-polymerase chain reaction, RT-PCR)检测血浆miRNAs表达。鉴定出差异表达最显著的两个miRNAs进行后续研究,用RT-PCR检测RDS发作期、出院时、出院后1个月时的miRNAs水平。用受试者工作特征曲线(Receiver operating characteristic curve,ROC)分析发作期时血浆miRNAs表达水平诊断RDS严重程度的价值。分析发作期时miRNAs表达水平与动脉血氧分压(Partial pressure of oxygen, PaO_(2))、二氧化碳分压(Partial pressure of carbon dioxide, PaCO_(2))、吸氧分数(Fraction of oxygen uptake, FiO_(2))、氧合指数(PaO_(2)/FiO_(2))、肌酸激酶同工酶(Creatine kinase isoenzyme, CK-MB)、乳酸脱氢酶(Lactic dehydrogenase, LDH)、超氧化物歧化酶(Superoxide dismutase, SOD)、丙二醛(Malondialdehyde, MDA)水平的相关性。结果测序结果显示,RDS新生患儿与健康新生儿血浆中共1 230种差异表达miRNAs,其中693种表达上调,537种表达下调。miRNA-200b及miRNA-449差异表达倍数>20,是差异性表达最显著的miRNAs。出院后1个月时RDS新生患儿血浆miRNA-200b及miRNA-449的表达水平均低于发作期和出院时(P<0.05),且出院时水平低于发作期(P<0.05)。血浆miRNA-200b、miRNA-449诊断RDS的曲线下面积(Area under curve,AUC)分别为0.702、0.763,灵敏度分别为73.6%、76.9%,特异度分别为69.8%、72.8%。血浆miRNA-200b与miRNA-449相对表达水平分别与PaO_(2)、PaO_(2)/FiO_(2)呈负相关(P<0.05),与PaCO_(2)、FiO_(2)呈正相关(P<0.05)。miRNA-200b、miRNA-449分别与CK-MB、LDH、MDA呈正相关(P<0.05),与SOD呈负相关(P<0.05)。结论 RDS新生患儿血浆miRNAs有明显异常表达,其中miRNA-200b、miRNA-449差异较为显著,二者在RDS新生患儿血浆中表达水平升高,且与呼吸功能损伤、心肌损伤和氧化应激损伤相关。

关键词：呼吸窘迫综合征 miRNA 心肌损伤氧化应激

罗沙司他治疗腹膜透析肾性贫血的有效性及安全性分析

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中国现代药物应用 2024年第19期18卷 86-88页

作者：邹雪军胡楚乔廖晨高安市人民医院肾内科 330800

目的探究罗沙司他治疗腹膜透析肾性贫血的有效性及安全性。方法选取50例腹膜透析肾性贫血患者,随机分成对照组和研究组,各25例。对照组接受重组人促红素注射液治疗,研究组接受罗沙司他治疗。对比两组治疗效果、贫血相关指标[血红蛋白(Hb... 详细信息

目的探究罗沙司他治疗腹膜透析肾性贫血的有效性及安全性。方法选取50例腹膜透析肾性贫血患者,随机分成对照组和研究组,各25例。对照组接受重组人促红素注射液治疗,研究组接受罗沙司他治疗。对比两组治疗效果、贫血相关指标[血红蛋白(Hb)、红细胞计数(RBC)、红细胞比容(Hct)]、不良反应发生率。结果研究组临床总有效率100.0%高于对照组的76.0%(P0.05);治疗4和12周后,研究组Hb、RBC、Hct水平分别为(92.3±5.6)g/L、(3.8±0.3)×10^(12)/L、(32.8±2.2)%和(100.2±8.9)g/L、(4.5±1.0)×10^(12)/L、(42.5±6.3)%,均高于对照组的(87.3±4.2)g/L、(3.2±1.0)×10^(12)/L、(27.9±3.0)%和(90.5±3.3)g/L、(3.9±0.8)×10^(12)/L、(33.0±2.3)%(P0.05)。结论对腹膜透析肾性贫血患者应用罗沙司他治疗的效果显著,可以有效提升贫血相关指标水平,且不良反应无明显增加,可保障患者的临床安全性。

关键词：罗沙司他腹膜透析肾性贫血重组人促红素注射液贫血指标安全性有效性

Nanostructure Architectures of Tungsten Carbide for Methanol Electrooxidation Catalyst

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Chinese Journal of Chemistry 2016年第6期34卷 624-630页

作者： Yekun Jiang Meiqin Shi xue Tong Youqun chu chunan Ma State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology College of Chemical Engineering Zhejiang University of Technology Hangzhou Zhejiang 310032 China

We reported a novel protocol to efficiently synthesize tungsten carbide （WC） nanomaterials with pure crystal structure and certain specific morphology. The key step in this protocol is the preparation of the catalyst precursor W18049 with surface oxygen vacancies. The existence of large quantities of oxygen vacancies gives plenty channels for diffusion and keeps the specific morphology of WC in the carbonization process. Efforts to build WC blocks with well-defined geometrical shapes （e.g., rods, wires, spheres and flakes） have further expanded its possibility to be the support for methanol electrooxidation catalyst. The platinum supported on pure phase WC materials served as an effective CO tolerant electrocatalyst for methanol oxidation. Electrochemical experiments indicated that the improved catalytic activity was related to the special morphologies of WC supports. Its sea urchin like feature leads to substantial interfaces between WC and Pt by preparing more anchor points for Pt loading and also the barriers for the subsequent crystal growth, which enhances the synergistic effect between WC and Pt.

关键词： carbides oxygen vacancy 3-dimensional block electrochemistry

The Light Regime Effect on Triacylglycerol Accumulation of Isochrysis zhangjiangensis

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Journal of Ocean University of China 2019年第2期18卷 474-480页

作者： FAN Xuran CAO Xupeng chu Yadong WU Peichun xue Song Marine Bioengineering Group Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

Stress state of microalgal cells is caused under unfavorable conditions such as disordered light regime and depleted nitrogen. The stress state can impair photosynthetic efficiency, inhibit cell growth and result in the accumulation of triacylglycerol(TAG) from protective mechanisms. Continuous light or nitrogen starvation was applied on microalgae and performed effectively on inducing TAG production. To evaluate the light regime effect on inducing TAG production, the effect of different light regimes on nitrogen-starved Isochrysis zhangjiangensis was investigated in this work. The continuous light and nitrogen starvation elevated TAG content of biomass by 73% and 193%, respectively. Furthermore, the TAG accumulation of I. zhangjiangensis cell under nitrogen starvation decreased under aggravated stress from continuous illumination. Our results demonstrated that culturing the cells with 14 L: 10 D light regime under nitrogen starvation is the optimal mode to achieve maximal accumulation of TAG. A recovery in light regime was necessary for I. zhangjiangensis cultivation.

关键词： microalgal cultivation triacylglycerol accumulation light regime Nitrogen starvation

Enhancement of Hydrogen Sorption on Metal（Ni, Rh, Pd） Functionalized Carbon Nanotubes： a DFT Study

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Chemical Research in Chinese Universities 2017年第3期33卷 422-429页

作者： XIAO Lu chu Wei SUN Wenjing xue Ying JIANG Chengfa School of Chemical Engineering Sichuan University Chengdu 610065 P. R. China China-America Cancer Research Institute Key Laboratory for Medical Molecular Diagnostics of Guangdong Province Guangdong Medical University Dongguan 523808 P. R. China

Hydrogen interacted with pristine single-walled carbon nanotubes（SWNTs） and single/dimer metal doped ones（M-CNTs） was investigated via density functional theory（DFT） simulations. The most stable configurations of Ni, Rh, Pd on SWNTs were identified. The interaction of H2 molecules with pristine SWNTs and M-CNTs was investigated. The results show that H2 molecules can be adsorbed on the pristine SWNTs via a weak physical interaction, which is much weaker than those of H2 molecules with M-CNTs by chemisorption. Each Ni, Rh and Pd doped SWNTs can respectively chemisorb three, two, or one H2 molecules and the H-H bond of H2 molecule is elongated. Furthermore, the H2 molecule could be dissociated owing to the presence of the Ni-Ni bond for Ni dimer doped SWNT, forming new Ni-H bonds. While such a dissociation could not be observed on RhJPd2-CNT samples. Density of state（DOS） results show that the s orbital of hydrogen can hybridize with the d orbital of metal atom, re- sulting in the stronger inteaction between H2 and M-CNTs, impying that the hydrogen storage capacity could be en- hanced in the presence of M-CNTs. The comparison of the interaction mechanism among different metals doped CNTs can screen out the most effective hydrogen-adsorption materials and the design of the related materials by computational approaches.

关键词： Hydrogen sorption Carbon nanotube Metal doped Density functional theory