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Recombinant chitinase-3-like protein 1 alleviates learning and memory impairments via M2 microglia polarization in postoperative cognitive dysfunction mice
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作者 Yujia Liu Xue Han +6 位作者 Yan Su Yiming Zhou Minhui Xu Jiyan Xu Zhengliang Ma Xiaoping Gu Tianjiao Xia 《Neural Regeneration Research》 SCIE CAS 2025年第9期2727-2736,共10页
Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life ... Postoperative cognitive dysfunction is a seve re complication of the central nervous system that occurs after anesthesia and surgery,and has received attention for its high incidence and effect on the quality of life of patients.To date,there are no viable treatment options for postoperative cognitive dysfunction.The identification of postoperative cognitive dysfunction hub genes could provide new research directions and therapeutic targets for future research.To identify the signaling mechanisms contributing to postoperative cognitive dysfunction,we first conducted Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of the Gene Expression Omnibus GSE95426 dataset,which consists of mRNAs and long non-coding RNAs differentially expressed in mouse hippocampus3 days after tibial fracture.The dataset was enriched in genes associated with the biological process"regulation of immune cells,"of which Chill was identified as a hub gene.Therefore,we investigated the contribution of chitinase-3-like protein 1 protein expression changes to postoperative cognitive dysfunction in the mouse model of tibial fractu re surgery.Mice were intraperitoneally injected with vehicle or recombinant chitinase-3-like protein 124 hours post-surgery,and the injection groups were compared with untreated control mice for learning and memory capacities using the Y-maze and fear conditioning tests.In addition,protein expression levels of proinflammatory factors(interleukin-1βand inducible nitric oxide synthase),M2-type macrophage markers(CD206 and arginase-1),and cognition-related proteins(brain-derived neurotropic factor and phosphorylated NMDA receptor subunit NR2B)were measured in hippocampus by western blotting.Treatment with recombinant chitinase-3-like protein 1 prevented surgery-induced cognitive impairment,downregulated interleukin-1βand nducible nitric oxide synthase expression,and upregulated CD206,arginase-1,pNR2B,and brain-derived neurotropic factor expression compared with vehicle treatment.Intraperitoneal administration of the specific ERK inhibitor PD98059 diminished the effects of recombinant chitinase-3-like protein 1.Collectively,our findings suggest that recombinant chitinase-3-like protein 1 ameliorates surgery-induced cognitive decline by attenuating neuroinflammation via M2 microglial polarization in the hippocampus.Therefore,recombinant chitinase-3-like protein1 may have therapeutic potential fo r postoperative cognitive dysfunction. 展开更多
关键词 Chil1 hippocampus learning and memory m2 microglia NEUROINFLAmmATION postoperative cognitive dysfunction(POCD) recombinant CHI3L1
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血清PKM2、Gal-3、CitH3水平升高可预测机械通气并发肺部感染
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作者 黄航栋 厉丹瑜 朱晓锋 《基础医学与临床》 CAS 2025年第1期86-90,共5页
目的探讨血清丙酮酸激酶M2(PKM2)、乳糖凝集素-3(Gal-3)、瓜氨酸化组蛋白H3(CitH3)水平与机械通气(MV)患者并发肺部感染的关系及预后评估价值。方法将2022年10月至2024年3月于金华市中心医院收治的120例行MV的患者纳入研究,根据是否并... 目的探讨血清丙酮酸激酶M2(PKM2)、乳糖凝集素-3(Gal-3)、瓜氨酸化组蛋白H3(CitH3)水平与机械通气(MV)患者并发肺部感染的关系及预后评估价值。方法将2022年10月至2024年3月于金华市中心医院收治的120例行MV的患者纳入研究,根据是否并发肺部感染分为肺部感染组(n=50)和非肺部感染组(n=70),ELISA检测血清PKM2、Gal-3、CitH3水平;收集临床资料;预后随访并分为预后良好组(n=79)和预后不良组(n=41);多因素Logistic回归分析影响MV患者发生预后不良的因素;受试者工作特征(ROC)曲线分析血清PKM2、Gal-3、CitH3对MV患者发生预后不良的预测价值。结果与非肺部感染组相比,肺部感染组血清PKM2、Gal-3、CitH3水平均升高(P<0.05);与预后良好组相比,预后不良组血清PKM2、Gal-3、CitH3水平均升高(P<0.05);预后不良组较预后良好组临床肺部感染评分(CPIS)升高(P<0.05);PKM2、Gal-3、CitH3皆为MV患者发生预后不良的危险因素(P<0.05);PKM2、Gal-3、CitH3及联合预测患者发生预后不良的曲线下面积(AUC)分别为0.712、0.839、0.779、0.925,3者联合诊断的AUC优于各自单独检测(Z=4.261、2.521、3.676,P<0.001、0.05、0.001)。结论MV并发肺部感染患者血清PKM2、Gal-3、CitH3水平均较未发生肺部感染患者升高,三者对MV患者发生预后不良有一定的预测价值。 展开更多
关键词 机械通气 肺部感染 丙酮酸激酶m2(PKm2) 乳糖凝集素-3(Gal-3) 瓜氨酸化组蛋白H3(CitH3) 预后
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Modification of Nano-α-Al2O3 and Its Influence on the Surface Properties of Waterborne Polyurethane Resin Composite Passivation Films
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作者 Jiankang Fu Changshuai Ma +2 位作者 Yameng Zhu Jing Yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第5期29-48,共20页
Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub&... Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> was determined by nano-particle size analyzer, and the effects of nano-α-Al<sub>2</sub>O<sub>3</sub> content, ethanol-aqueous solution ratio and KH560 dosage on the dispersion and particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> were investigated. The material structure before and after modification was determined by Fourier transform infrared spectroscopy (FTIR). Aqueous polyurethane resin and inorganic components are combined with modified nano-α-Al<sub>2</sub>O<sub>3</sub> dispersion to form chromium-free passivation solution. The solution is coated on the galvanized sheet, the adhesion and surface hardness are tested, the bonding strength of the coating and the surface hardness of the substrate are discussed. The corrosion resistance and surface morphology of the matrix were investigated by electrochemical test, neutral salt spray test and scanning electron microscope test. The chromium-free passivation film formed after the modification of nano-α-Al<sub>2</sub>O<sub>3</sub> increases the surface hardness of galvanized sheet by about 85%. The corrosion resistance of the film is better than that of a single polyurethane film. The results show that the surface hardness and corrosion resistance of polyurethane resin composite passivation film are significantly improved by the introduction of nano-α-Al<sub>2</sub>O<sub>3</sub>. 展开更多
关键词 micro-nano α-Al2O3 Waterborne Polyurethane Resin Particle Size Surface Hardness Corrosion Resistance
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NaNO_2对20SiMn低合金钢在3%NaCl溶液中空蚀损伤的缓蚀作用 被引量:3
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作者 骆素珍 郑玉贵 +2 位作者 敬和民 姚治铭 柯伟 《腐蚀科学与防护技术》 CAS CSCD 北大核心 2004年第6期347-351,共5页
利用磁致伸缩空蚀实验机研究了 2 0SiMn低合金钢在 3%NaCl和 3%NaCl+NaNO2 溶液中的空蚀行为 .测量了静态和空蚀条件下的腐蚀电位变化、电化学阻抗谱和极化曲线 .结果表明 :NaNO2 通过抑制腐蚀与空蚀间的交互作用 ,对 2 0SiMn低合金钢在... 利用磁致伸缩空蚀实验机研究了 2 0SiMn低合金钢在 3%NaCl和 3%NaCl+NaNO2 溶液中的空蚀行为 .测量了静态和空蚀条件下的腐蚀电位变化、电化学阻抗谱和极化曲线 .结果表明 :NaNO2 通过抑制腐蚀与空蚀间的交互作用 ,对 2 0SiMn低合金钢在 3%NaCl溶液中的空蚀损伤有良好的抑制作用 ,浓度为 1%的NaNO2 的缓蚀效率达到80 2 % .添加NaNO2 对 2 0SiMn低合金钢在 3%NaCl溶液中的电化学行为有显著影响 .在 3%NaCl溶液中 ,自腐蚀电位、线性极化电阻都随空蚀进行而逐渐负移和减小 .与此相反 ,添加NaNO2 后 ,2 0SiMn的自腐蚀电位、线性极化电阻都随空蚀的进行而逐渐正移和增大 .3%NaCl+1%NaNO2 溶液中的电化学阻抗谱特征与空蚀表面形貌的变化有较好的对应关系 . 展开更多
关键词 低合金钢 自腐蚀电位 3%NaCl溶液 空蚀 缓蚀作用 nano2 电化学阻抗谱 损伤 中空 抑制作用
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复合添加MgO和La_(2)O_(3)对纳米微晶氧化铝陶瓷微观结构的影响
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作者 李慧 张金平 +2 位作者 高景霞 王二萍 张洋洋 《硅酸盐通报》 CAS 北大核心 2024年第1期339-346,共8页
纳米微晶氧化铝磨料具有良好的通用性和高精度磨削能力,且性价比较高,在机械制造、轴承、模具、汽车等领域有广泛的应用潜力。本研究以勃姆石(γ-AlOOH)为原料,MgO、La_(2)O_(3)为添加剂,采用溶胶-凝胶工艺合成纳米微晶氧化铝。通过差... 纳米微晶氧化铝磨料具有良好的通用性和高精度磨削能力,且性价比较高,在机械制造、轴承、模具、汽车等领域有广泛的应用潜力。本研究以勃姆石(γ-AlOOH)为原料,MgO、La_(2)O_(3)为添加剂,采用溶胶-凝胶工艺合成纳米微晶氧化铝。通过差示扫描量热仪、X射线衍射仪、扫描电子显微镜和从头算分子动力学方法模拟计算研究了添加剂对微晶氧化铝相转化、物相组成、微观结构及力学性能的影响。结果表明:复合添加MgO和La2O3可以使氧化铝中间相θ-Al_(2)O_(3)向α-Al_(2)O_(3)转化的温度从1257℃降低到1105℃,将致密化温度从1600℃降低到1350℃,将微晶氧化铝的晶粒尺寸从1.04 mm减小到120 nm,实现了低温致密烧结。 展开更多
关键词 纳米微晶 Al_(2)O_(3) mGO La_(2)O_(3) 溶胶-凝胶 添加剂 低温烧结
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超声造影联合血清Ficolin-3,FOXM1对2型糖尿病下肢动脉病变的诊断价值分析
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作者 何兰芳 康佳 +2 位作者 沙晓溪 吕德 康彧 《四川医学》 CAS 2024年第9期983-988,共6页
目的超声造影联合血清纤维胶凝蛋白-3(Ficolin-3)、叉头框蛋白M1(FOXM1)对2型糖尿病(T2DM)下肢动脉病变的诊断价值分析。方法选取2022年2月至2023年2月我院收治的T2DM患者114例,以下肢动脉血管造影检查为金标准,将患者分为下肢动脉病变... 目的超声造影联合血清纤维胶凝蛋白-3(Ficolin-3)、叉头框蛋白M1(FOXM1)对2型糖尿病(T2DM)下肢动脉病变的诊断价值分析。方法选取2022年2月至2023年2月我院收治的T2DM患者114例,以下肢动脉血管造影检查为金标准,将患者分为下肢动脉病变组23例(病变组)和无下肢动脉病变组91例(T2DM组),另选取同期于本院进行体检的健康志愿者91例为对照组。对患者及健康志愿者进行血清Ficolin-3、FOXM1及超声造影检查;ROC曲线分析血清Ficolin-3、FOXM1对T2DM下肢动脉病变的诊断价值;采用四格表法分析血清Ficolin-3、FOXM1、超声造影及3项联合对T2DM下肢动脉病变的诊断价值。结果病变组、T2DM组血清Ficolin-3水平显著高于对照组,且病变组血清Ficolin-3水平显著高于T2DM组(均P<0.05);病变组、T2DM组血清FOXM1水平显著低于对照组,且病变组血清FOXM1水平显著低于T2DM组(均P<0.05);血清Ficolin-3诊断T2DM下肢动脉病变的曲线下面积为0.868,敏感度为86.96%,特异度为75.82%,最佳截断值为35.12μg/ml;血清FOXM1诊断T2DM下肢动脉病变的曲线下面积为0.854,敏感度为82.61%,特异度为78.02%,最佳截断值为0.57;血清Ficolin-3、FOXM1检查结果与金标准均具有中度一致性(Kappa=0.480、0.481,均P<0.001);超声造影检查结果显示,T2DM下肢动脉病变的阳性检出率为73.91%,与金标准具有较高一致性(Kappa=0.631,P<0.001);3项联合检测的敏感度、漏诊率均显著优于超声造影单独诊断,准确度显著优于Ficolin-3、FOXM1单独诊断,差异均有统计学意义(均P<0.05)。结论血清Ficolin-3、FOXM1联合超声造影检查在T2DM下肢动脉病变诊断中的应用价值较高,进一步提升了诊断的敏感度、准确度,减少了误诊率。 展开更多
关键词 超声造影 纤维胶凝蛋白-3 叉头框蛋白m1 2型糖尿病 下肢动脉病变
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转基因抗虫玉米LG11中m2cryAb-vip3A融合基因及其蛋白的表达分析
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作者 李文兰 崔洁 +3 位作者 李冬梅 李海涛 孟昭东 岳润清 《山东农业科学》 北大核心 2024年第6期25-29,共5页
抗虫转基因作物中杀虫蛋白的表达量对抗虫效果至关重要,研究外源Bt基因在作物不同生育时期和不同组织器官中的时空表达模式,对于抗虫转基因玉米产业化后的害虫抗性治理和农业转基因生物安全管理具有重要意义。LG11抗虫转基因玉米中的抗... 抗虫转基因作物中杀虫蛋白的表达量对抗虫效果至关重要,研究外源Bt基因在作物不同生育时期和不同组织器官中的时空表达模式,对于抗虫转基因玉米产业化后的害虫抗性治理和农业转基因生物安全管理具有重要意义。LG11抗虫转基因玉米中的抗虫基因是山东省农业科学院通过人工合成方法将外源Bt杀虫蛋白Cry1Ab和Vip3Aa的主要结构域组合形成的新型抗虫融合蛋白M2cryAb-vip3A,连续两年对该转化体材料抗虫基因m2cryAb-vip3A的表达模式进行分析,利用实时定量PCR方法从转录水平对LG11苗期的根、茎和叶,吐丝期的根和茎,成熟期的根、叶和籽粒中的m2cryAb-vip3A基因的表达模式进行分析;利用酶联免疫吸附法(ELISA)从翻译水平对苗期的根、茎和叶,吐丝期的根、茎、花丝和花粉,成熟期的根、茎、叶、籽粒和苞叶中的M2cryAb-vip3A蛋白表达量进行测定。结果表明,m2cryAb-vip3A抗虫融合基因及其编码蛋白在抗虫转基因玉米不同生育时期的不同组织器官中表达差异较大,以幼苗期叶片中的表达量最高。该研究结果可为LG11未来的商业化推广和农业转基因生物安全管理提供有用的信息。 展开更多
关键词 m2cryAb-vip3A 表达模式 转基因 玉米
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PKM2通过调控活性氧依赖的PI3K/Akt信号通路影响膀胱尿路上皮细胞癌细胞的侵袭能力
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作者 梁凯 殷磊 陈琦 《中国医科大学学报》 CAS 北大核心 2024年第7期621-627,634,共8页
目的 探讨PKM2通过调控活性氧(ROS)依赖的PI3K/Akt信号通路对膀胱尿路上皮细胞癌细胞侵袭能力的影响。方法 将人膀胱癌T24细胞随机分为Control组、si-NC组、si-PKM2组和si-PKM2+IGF-1组。实时PCR检测细胞中PKM2 mRNA表达;CCK-8检测细胞... 目的 探讨PKM2通过调控活性氧(ROS)依赖的PI3K/Akt信号通路对膀胱尿路上皮细胞癌细胞侵袭能力的影响。方法 将人膀胱癌T24细胞随机分为Control组、si-NC组、si-PKM2组和si-PKM2+IGF-1组。实时PCR检测细胞中PKM2 mRNA表达;CCK-8检测细胞增殖;Transwell小室法检测细胞侵袭和转移;Hoechst 33342荧光染色和流式细胞术检测细胞凋亡;ROS荧光探针法检测细胞中ROS水平;Western blotting检测细胞中PI3K、Akt、mTOR、caspase-3、Bax、Bcl-2蛋白表达。结果 与人正常膀胱上皮SV-HUC-1细胞相比,人膀胱癌T24细胞中PKM2 mRNA相对表达量明显增加(P <0.05)。与Control组相比,si-PKM2组T24细胞中PKM2 mRNA相对表达量、细胞增殖能力、侵袭细胞数以及细胞中p-PI3K/PI3K、p-Akt/Akt、p-mTOR/mTOR比值和Bcl-2蛋白表达水平明显降低(P <0.05),细胞凋亡率、细胞中ROS相对水平以及细胞中Bax、caspase-3蛋白表达水平明显升高(P <0.05);与siPKM2组相比,si-PKM2+IGF-1组T24细胞中PKM2 mRNA相对表达量、细胞增殖能力、侵袭细胞数以及细胞中p-PI3K/PI3K、p-Akt/Akt、p-mTOR/mTOR比值和Bcl-2蛋白表达水平明显升高(P <0.05),细胞凋亡率、细胞中ROS相对水平以及细胞中Bax、caspase-3蛋白表达水平明显降低(P <0.05)。结论 敲减PKM2可促进膀胱尿路上皮细胞癌细胞中ROS水平升高,抑制PI3K/Akt/mTOR信号通路激活,进而发挥抑制细胞侵袭和促进细胞凋亡作用。 展开更多
关键词 m2型丙酮酸激酶 膀胱尿路上皮细胞癌 活性氧 PI3K/Akt/mTOR信号通路
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泽泻汤基于PI3K/AKT通路调节巨噬细胞M1/M2极化平衡机制研究 被引量:2
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作者 李二稳 崔正浩 +6 位作者 高改 付中学 张效威 王辉 张振强 徐江雁 谢治深 《中国免疫学杂志》 CAS CSCD 北大核心 2024年第8期1684-1691,I0001,共9页
目的:探讨泽泻汤(ZXT)对巨噬细胞M1/M2极化平衡的影响及可能的作用机制。方法:体内使用西式饮食(WD)诱导脂代谢紊乱小鼠模型,体外通过LPS/IL-4诱导RAW264.7细胞M1/M2型巨噬细胞模型,设置空白组、模型组、ZXT组。采用免疫荧光染色观察脂... 目的:探讨泽泻汤(ZXT)对巨噬细胞M1/M2极化平衡的影响及可能的作用机制。方法:体内使用西式饮食(WD)诱导脂代谢紊乱小鼠模型,体外通过LPS/IL-4诱导RAW264.7细胞M1/M2型巨噬细胞模型,设置空白组、模型组、ZXT组。采用免疫荧光染色观察脂肪组织和RAW264.7细胞M1、M2型巨噬细胞标志物荧光强度;Western blot检测p-AKT、AKT、COX-2蛋白水平;qPCR分析M1、M2型巨噬细胞标志基因mRNA水平;ELISA测定IL-1β、IL-10分泌量;Griess法检测NO含量;Docking分析泽泻、白术活性成分与PI3K蛋白的结合情况。结果:与WD组相比,ZXT组CD11c表达显著减少,CD206表达量显著上调;ZXT逆转了LPS诱导的CD80表达升高,下调M1型巨噬细胞标志基因iNOS等mRNA水平,降低COX-2蛋白表达,抑制IL-1β分泌;ZXT促进IL-4诱导的CD206表达,上调M2型巨噬细胞标志基因Arg-1等mRNA水平及IL-10的分泌;ZXT逆转了LPS引起的NO释放增加;ZXT给药后体内外p-AKT/AKT蛋白水平均上升;Docking结果显示泽泻、白术中多个活性成分可与PI3K蛋白形成氢键稳定结合。结论:泽泻汤调节巨噬细胞M1/M2极化平衡,其作用机制可能与调控PI3K/AKT通路有关。 展开更多
关键词 泽泻汤 巨噬细胞 m1/m2极化 PI3K/AKT通路
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Doping effect of cations(Zr^(4+),Al^(3+),and Si^(4+)) on MnO_x/CeO_2 nano-rod catalyst for NH_3-SCR reaction at low temperature 被引量:7
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作者 Xiaojiang Yao Jun Cao +4 位作者 Li Chen Keke Kang Yang Chen Mi Tian Fumo Yang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第5期733-743,共11页
Thermally stable Zr4+, Al3+, and Si4+ cations were incorporated into the lattice of CeO2 nano‐rods (i.e., CeO2‐NR) in order to improve the specific surface area. The undoped and Zr4+, Al3+, and Si4+ doped nano‐rods... Thermally stable Zr4+, Al3+, and Si4+ cations were incorporated into the lattice of CeO2 nano‐rods (i.e., CeO2‐NR) in order to improve the specific surface area. The undoped and Zr4+, Al3+, and Si4+ doped nano‐rods were used as supports to prepare MnOx/CeO2‐NR, MnOx/CZ‐NR, MnOx/CA‐NR, and MnOx/CS‐NR catalysts, respectively. The prepared supports and catalysts were comprehensively characterized by transmission electron microscopy (TEM), high‐resolution TEM, X‐ray diffraction, Raman and N2‐physisorption analyses, hydrogen temperature‐programmed reduction, ammonia temperature‐programmed desorption, in situ diffuse reflectance infrared Fourier‐transform spectroscopic analysis of the NH3 adsorption, and X‐ray photoelectron spectroscopy. Moreover, the catalytic performance and H2O+SO2 tolerance of these samples were evaluated through NH3‐selective catalytic reduction (NH3‐SCR) in the absence or presence of H2O and SO2. The obtained results show that the MnOx/CS‐NR catalyst exhibits the highest NOx conversion and the lowest N2O concentration, which result from the largest number of oxygen vacancies and acid sites, the highest Mn4+ content, and the lowest redox ability. The MnOx/CS‐NR catalyst also presents excellent resistance to H2O and SO2. All of these phenomena suggest that Si4+ is the optimal dopant for the MnOx/CeO2‐NR catalyst. 展开更多
关键词 mnOx/CeO2 nano‐rod catalyst Doping effect Oxygen vacancy Surface acidity Low‐temperature NH3‐SCR reaction
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Microstructure,mechanical response and fractography of AZ91E/Al_(2)O_(3)_(p) nano composite fabricated by semi solid stir casting method 被引量:6
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作者 Sameer Kumar D Suman K.N.S +2 位作者 Tara Sasanka C Ravindra K Palash Poddar 《Journal of Magnesium and Alloys》 SCIE EI CAS 2017年第1期48-55,共8页
The present study confers to the fabrication and its characterization of magnesium alloy(AZ91E)based nano composites with nano Al_(2)O_(3) particulate reinforcements.A novel Semi Solid stir casting technique was adopt... The present study confers to the fabrication and its characterization of magnesium alloy(AZ91E)based nano composites with nano Al_(2)O_(3) particulate reinforcements.A novel Semi Solid stir casting technique was adopted for the fabrication of the composite.An average particle size of 50 nm was used as reinforcement to disperse in matrix.The effects of change in weight fraction of reinforcements on the distribution of particles,particle–matrix interfacial reactions,physical as well as mechanical properties were reported.The SEM and EDS analysis has shown the uniform distribution of particles in the composite along with the presence of elements.The mechanical properties of reinforced and unreinforced composite were evaluated and presented.Fractography of tensile specimens was also discussed. 展开更多
关键词 magnesium alloys nano composites Semi solid stir casting Al_(2)O_(3)particle
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Enhancement of catalytic activity by homo-dispersing S_2O_8^(2–)-Fe_2O_3 nanoparticles on SBA-15 through ultrasonic adsorption 被引量:4
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作者 Qingyan Chu Jing Chen +6 位作者 Wenhua Hou Haoxuan Yu Ping Wang Rui Liu Guangliang Song Hongjun Zhu Pingping Zhao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第5期955-963,共9页
Mesoporous superacids S2O82–-Fe2O3/SBA-15(SFS)with active nanoparticles are prepared by ultrasonic adsorption method.This method is adopted to ensure a homo-dispersed nanoparticle active phase,large specific surface ... Mesoporous superacids S2O82–-Fe2O3/SBA-15(SFS)with active nanoparticles are prepared by ultrasonic adsorption method.This method is adopted to ensure a homo-dispersed nanoparticle active phase,large specific surface area and many acidic sites.Compared with bulk S2O82–-Fe2O3,Br?nsted acid catalysts and other reported catalysts,SFS with an Fe2O3 loading of 30%(SFS-30)exhibits an outstanding activity in the probe reaction of alcoholysis of styrene oxide by methanol with 100%yield.Moreover,SFS-30 also shows a more excellent catalytic performance than bulk S2O82–-Fe2O3 towards the alcoholysis of other ROHs(R=C2H5-C4H9).Lewis and Bronsted acid sites on the SFS-30 surfaces are confirmed by pyridine adsorbed infrared spectra.The highly efficient catalytic activity of SFS-30 may be attributed to the synergistic effect from the nano-effect of S2O82–-Fe2O3 nanoparticles and the mesostructure of SBA-15.Finally,SFS-30 shows a good catalytic reusability,providing an 84.1%yield after seven catalytic cycles. 展开更多
关键词 mesoporous superacid nanoparticle nano effect S2O82–-Fe2O3/SBA-15 Acidic site Ultrasonic adsorption ALCOHOLYSIS
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Fabrication and Mechanical Properties of Sm2O3 Doped CeO2 Reinforced Ti3AlC2 Nano Composite 被引量:1
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作者 Jae Ho Han Sang Whan Park Young Do Kim 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第z2期85-88,共4页
The fabrication process of Sm2O3 doped CeO2 reinforced Ti3AlC2 nano composites including the nano particle dispersion process by a hetero-coagulation process was developed using in-situ synthesis and densification pro... The fabrication process of Sm2O3 doped CeO2 reinforced Ti3AlC2 nano composites including the nano particle dispersion process by a hetero-coagulation process was developed using in-situ synthesis and densification process of Ti3AlC2. The effects of Sm2O2 doped CeO2 nano particles on mechanical properties of Ti3AlC2 were investigated. It was found that the presence of 20SDC nano particles in Ti3AlC2 was very effective to improve the mechanical properties of Ti3AlC2 without spoiling the unique characteristics of Ti3AlC2temary carbide. 展开更多
关键词 nano CERAmIC composite TI3ALC2 CEO2 FABRICATION RARE earths
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m(ZnO)/m(B_(2)O_(3))质量比对低熔点封接玻璃Bi_(2)O_(3)-B_(2)O_(3)-ZnO结构、性能与润湿性的影响
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作者 康涛 熊春荣 +4 位作者 符有杰 蔡邦辉 魏曙光 李军葛 姜宏 《硅酸盐通报》 CAS 北大核心 2024年第4期1341-1349,共9页
针对真空玻璃封接的性能要求,本文采用高温熔融法制备了一种针对真空玻璃封接的铋系非晶无铅玻璃粉,通过高温X射线衍射、粉末X射线衍射、拉曼光谱、差式扫描量热仪、热膨胀测试和扫描电子显微镜等测试方法,研究了m(ZnO)/m(B_(2)O_(3))... 针对真空玻璃封接的性能要求,本文采用高温熔融法制备了一种针对真空玻璃封接的铋系非晶无铅玻璃粉,通过高温X射线衍射、粉末X射线衍射、拉曼光谱、差式扫描量热仪、热膨胀测试和扫描电子显微镜等测试方法,研究了m(ZnO)/m(B_(2)O_(3))质量比对Bi_(2)O_(3)-B_(2)O_(3)-ZnO玻璃的网络结构、特征温度、热膨胀系数和封接温度的影响。结果表明,增加m(ZnO)/m(B_(2)O_(3))质量比可促进锌氧多面体由[ZnO_(4)]向[ZnO_(6)]转变,导致热膨胀系数降低,特征温度升高。当m(Bi_(2)O_(3))∶m(B_(2)O_(3))∶m(ZnO)质量比为80∶7∶13,玻璃具有较低的玻璃化转变温度T_(g)(371℃)和膨胀软化温度T_(f)(401℃),热膨胀系数为9.3×10^(-6)℃^(-1),封接温度为450℃,可满足真空玻璃封接对低熔点封接玻璃粉的要求。 展开更多
关键词 m(ZnO)/m(B_(2)O_(3))质量比 特征温度 Bi_(2)O_(3)-B_(2)O_(3)-ZnO玻璃 真空玻璃 封接温度 封接玻璃粉
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m-LLDPE/nano-SiO_2复合材料的性能和形态结构研究 被引量:3
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作者 李海东 庞洪宝 +1 位作者 程凤梅 杜春龙 《塑料科技》 CAS 北大核心 2005年第5期45-48,共4页
采用沉降法对纳米SiO2进行表面处理,用熔融共混法制备了m-LLDPE/纳米SiO2复合材料。研究了该复合材料的力学性能和光学性能。结果表明:随着纳米SiO2的加入,其复合材料的缺口冲击强度和拉伸强度呈峰形变化,断裂伸长率略有下降。当加入少... 采用沉降法对纳米SiO2进行表面处理,用熔融共混法制备了m-LLDPE/纳米SiO2复合材料。研究了该复合材料的力学性能和光学性能。结果表明:随着纳米SiO2的加入,其复合材料的缺口冲击强度和拉伸强度呈峰形变化,断裂伸长率略有下降。当加入少量的纳米SiO2后,复合材料的红外线吸收能力较m-LLDPE明显提高;此外,m-LLDPE/纳米SiO2复合材料的可见光透过率有所降低,雾度却有明显的先上升后下降趋势。通过SEM得出,表面处理对纳米SiO2在基体中的分散性有显著的改善。 展开更多
关键词 茂金属线型低密度聚乙烯 纳米二氧化硅 力学性能 光学性能
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Magnetic Nano Cobalt Ferrite Catalyzed Synthesis of 4H-Pyrano[3,2-h]quinoline Derivatives under Microwave Irradiation 被引量:1
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作者 Swathi Bandaru Ravi K. Majji +6 位作者 Satyanarayana Bassa Pandu N. Chilla Ramesh Yellapragada Sruthi Vasamsetty Rajendra K. Jeldi Raghu B. Korupolu Paul D. Sanasi 《Green and Sustainable Chemistry》 2016年第2期101-109,共9页
A microwave irradiated magnetically separable nano cobalt ferrite catalyzed green method for the synthesis of 4-phenyl-4H-pyrano[3,2-h]quinolin-2-amine and 2-amino-4-phenyl-4H-pyrano[3,2-h] quinoline-3-carbonitrile de... A microwave irradiated magnetically separable nano cobalt ferrite catalyzed green method for the synthesis of 4-phenyl-4H-pyrano[3,2-h]quinolin-2-amine and 2-amino-4-phenyl-4H-pyrano[3,2-h] quinoline-3-carbonitrile derivatives through cyclization of aromatic aldehyde, acetonitrile/malononitrile and 8-hydoxyquinoline is developed and presented in this paper. The cubic magnetic cobalt ferrite nano particles were synthesized by sol-gel citrate precursor method and characterized by FT-IR, XRD, SEM and TEM techniques and the structures of the synthesized pyranoquinoline derivatives were assigned by IR, MASS and 1</sup>H NMR techniques. The reaction is carried out in a domestic microwave oven with a heat-resistant microwave safe glass container with a lid. 展开更多
关键词 Synthesis of 4H-Pyrano[3 2-h]quinoline Derivatives microwave Irradiation nano Cobalt Ferrite Catalyst
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基于P2X3、M2受体探讨五苓散对骶髓损伤后逼尿肌无反射型神经源性膀胱大鼠的作用机制
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作者 王杨 张琳 王振亮 《时珍国医国药》 CAS CSCD 北大核心 2024年第7期1615-1619,共5页
目的探讨五苓散改善骶髓损伤后逼尿肌无反射型神经源性膀胱(NB)大鼠的作用靶点,揭示五苓散促进膀胱气化功能恢复的作用机制,为临床干预脊髓损伤后NB患者提供理论基础。方法将SD大鼠随机分为假手术组和造模组,造模组采用改良Hassan Shake... 目的探讨五苓散改善骶髓损伤后逼尿肌无反射型神经源性膀胱(NB)大鼠的作用靶点,揭示五苓散促进膀胱气化功能恢复的作用机制,为临床干预脊髓损伤后NB患者提供理论基础。方法将SD大鼠随机分为假手术组和造模组,造模组采用改良Hassan Shaker脊髓横断法建立NB模型,将造模成功的大鼠随机分为模型组、五苓散高、中、低剂量组。假手术组只咬除椎板,暴露骶髓,不进行骶髓横断处理。用HE染色观察膀胱组织形态学变化,生化法检测膀胱组织中三磷酸腺苷(ATP)、乙酰胆碱(Ach)含量,RT-PCR和Western blot法检测大鼠膀胱组织中膀胱嘌呤能受体(P2X3)、毒蕈碱型胆碱能受体(M2)mRNA及蛋白表达水平。结果模型组与假手术组比较:ATP、Ach含量减少,P2X3、M2受体mRNA及蛋白表达降低,差异有统计学意义(P<0.01);五苓散各组治疗14天后与模型组比较:ATP、Ach含量增加,P2X3、M2受体mRNA及蛋白表达升高,差异均有统计学意义(P<0.05),且差异与五苓散用药剂量成正相关。结论五苓散治疗可改善骶髓损伤后逼尿肌无反射型NB大鼠的膀胱功能,减轻尿潴留症状,其机制可能与促进膀胱中ATP、Ach的释放以及上调P2X3和M2受体表达有关。 展开更多
关键词 骶髓损伤 神经源性膀胱 逼尿肌无反射型 P2X3受体 m2受体 五苓散
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A Solid Phase Extraction Application of Hybrid Nano B2O3/ZrO2 for Separation and Determination of Trace Indium in Environmental Samples
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作者 Ozcan Yalcinkaya Harun Ciftci +2 位作者 Cigdem Er Caliskan Ozge Kalender Ali Rehber Turker 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2018年第4期1283-1289,共7页
Hybrid nanomaterials have attracted considerable interest in environmental science,analytical chemistry and atomic spectroscopy.In the present study,a column solid phase extractioo procedure was developed for the sepa... Hybrid nanomaterials have attracted considerable interest in environmental science,analytical chemistry and atomic spectroscopy.In the present study,a column solid phase extractioo procedure was developed for the separation and preconcentration of indium in various matrixes by using hybrid nanomaterial B_2O_3/ZrO_2(HNMBZ).Various experimental and analytical parameters such as sample solution pH,sample solution volume,flow rate of sample solution and eluent,volume and concentration of eluent aod amount of HNMBZ,effect of common matrix ions and capacity of sorbent were investigated.The adsorbed metal ions on HNMBZ were eluted with 6mL of 1mol·L^(-1 )HNO_3solutions and their concentrations were determined by high-resolution continuum source flame atomic absorption spectrometry(HR-CS FAAS).Under the optimized conditions,detection limits for indium for 3pixels and 5pixels were found as 0.20and 0.16μg·L^(-1),respectively.The accuracy of the procedure was checked by spiked water samples.The developed procedure was successfully applied to real samples for the separation and determination of indium. 展开更多
关键词 PRECONCENTRATION INDIUm nano B2O3/ZrO2 Water ATOmIC absorption SPECTROmETRY
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基于lncRNA H19的m6A甲基化调控S1PR2/TLR4/NLRP3通路探讨电针血清对缺血性脑卒中后血脑屏障的作用机制
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作者 张浛芮 吕鹤群 +2 位作者 曾春利 沈燕 彭拥军 《世界科学技术-中医药现代化》 CSCD 北大核心 2024年第10期2716-2725,共10页
目的从lncRNA H19的m6A甲基化调控S1PR2/TLR4/NLRP3通路的角度,探讨电针血清对缺血性脑卒中后血脑屏障的作用机制。方法电针血清的制备:建立改良的大鼠局灶性脑缺血再灌注模型,分别在缺血后5 min、再灌注24 h和48 h进行3次电针干预,针... 目的从lncRNA H19的m6A甲基化调控S1PR2/TLR4/NLRP3通路的角度,探讨电针血清对缺血性脑卒中后血脑屏障的作用机制。方法电针血清的制备:建立改良的大鼠局灶性脑缺血再灌注模型,分别在缺血后5 min、再灌注24 h和48 h进行3次电针干预,针刺人中、百会穴,并接电针仪治疗30 min。3次电针干预后取大鼠血清备用。细胞实验:将脑微血管内皮细胞和周细胞共培养的血脑屏障模型分为对照组、模型组、电针组、电针联合METTL3过表达组与电针联合lncRNA H19过表达组。除对照组外,其余各组氧糖剥夺2 h后再复氧、复糖24 h,并于复氧、复糖的同时给予电针血清、METTL3过表达慢病毒及lncRNA H19过表达慢病毒处理。本实验采用跨内皮细胞电阻和Na-F通透性检测血脑屏障模型的功能;比色法检测总RNA m6A修饰定量;Western blot检测METTL3、ZO-1、S1PR2、TLR4和NLRP3蛋白水平的表达;qPCR检测METTL3、ZO-1、S1PR2、TLR4、NLRP3和lncRNA H19 mRNA的表达。结果与模型组相比,电针组的跨内皮细胞电阻值增高(P<0.01);Na-F值降低(P<0.01);总RNA m6A修饰水平降低(P<0.01);METTL3、S1PR2、TLR4、NLRP3和lncRNA H19表达水平下调(P<0.01),ZO-1蛋白与mRNA表达上调(P<0.01)。与电针组相比,电针联合METTL3和lncRNA H19过表达组的跨内皮细胞电阻值降低(P<0.05);Na-F值增高(P<0.01);总RNA m6A修饰水平增高(P<0.01),METTL3、S1PR2、TLR4、NLRP3和lncRNA H19表达上调(P<0.05),ZO-1蛋白与mRNA表达下调(P<0.01)。结论电针血清对氧糖剥夺再灌注后血脑屏障模型具有保护作用,其机制可能是电针通过lncRNA H19的m6A甲基化下调S1PR2/TLR4/NLRP3通路,从而减轻缺血性脑卒中后血脑屏障损伤。 展开更多
关键词 缺血性脑卒中 电针 血脑屏障 m6A甲基化 S1PR2/TLR4/NLRP3
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Tape Casting of Al_2O_3-TiB_2/Al_2O_3-Nano-TiC Multilayer Composites
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作者 Yuping ZENG Dongliang JIANG Shouhong TAN and Jingkun GUO(Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第4期324-326,共3页
Ceramic tapes, containing Al2O3-25 wt pct TiB2(B) and Al2O3-25 wt pct nano-TiC (c), have been obtained by tape casting process. Numerous tapes (about 60~80 tapes) were prepared by stacking in turn the composition (B)... Ceramic tapes, containing Al2O3-25 wt pct TiB2(B) and Al2O3-25 wt pct nano-TiC (c), have been obtained by tape casting process. Numerous tapes (about 60~80 tapes) were prepared by stacking in turn the composition (B) and (C), laminating under 10 MPa pressure, eliminating the solvent and burning out the polymer additives. The final green bodies were hot pressed at 1750℃ and 30 MPa. The composite has a bending strength of 568 MPa and a fracture toughness of 5.8 M Pa·m1/2. SEM analysis exhibits that Al2O3 particle growth was inhibited by TiC particles in C. but TiB2 particles could not hinder Al2O3 growth in B. The curves of GTA indicates that all organic additives could be removed completely above 600℃ 展开更多
关键词 nano TIB AL Tape Casting of Al2O3-TiB2/Al2O3-nano-TiC multilayer Composites TIC
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