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静电纺丝制备纳米纤维束及其应用 预览
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作者 唐寅 顾雪萍 +1 位作者 冯连芳 张才亮 《高校化学工程学报》 EI CAS CSCD 北大核心 2019年第4期765-774,共10页
纳米纤维束独特的微纳结构赋予其较大的比表面积、粗糙度和孔隙率等特性,在生物医学、催化、传感、过滤和吸附等领域具有广泛的应用前景。然而,常规制备纳米纤维的方法如自组装法、模板法和熔喷法等,很难制备出纤维束;传统的静电纺丝法... 纳米纤维束独特的微纳结构赋予其较大的比表面积、粗糙度和孔隙率等特性,在生物医学、催化、传感、过滤和吸附等领域具有广泛的应用前景。然而,常规制备纳米纤维的方法如自组装法、模板法和熔喷法等,很难制备出纤维束;传统的静电纺丝法所制备的纤维束的“束”尺寸基本在微米级以上,如何制备较小“束”尺寸的纳米纤维束是提高材料性能及应用开发的关键。文章首先介绍了近年来通过改进静电纺丝工艺和设备制备纳米纤维束的各种方法,进而总结了纳米纤维束的特点和应用,最后提出了纳米纤维束研究亟待解决的问题。 展开更多
关键词 静电纺丝 纳米纤维 纤维束 聚合物纤维
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CO2在三聚氰胺酚醛纤维上的吸附分离 预览
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作者 周智慧 金灿 +3 位作者 张豪益 梁晓蕾 张富民 肖强 《燃料化学学报》 EI CAS CSCD 北大核心 2019年第2期242-248,共7页
以三聚氰胺、间苯三酚和甲醛为原料,通过水热缩聚反应合成了三聚氰胺酚醛纤维(PMF),考察了温度对PMF合成的影响。以扫描电子显微镜(SEM)、透射电子显微镜(TEM)、N2吸脱附和傅里叶变换红外(FTIR)光谱等表征了PMF的形貌和结构,并采用体积... 以三聚氰胺、间苯三酚和甲醛为原料,通过水热缩聚反应合成了三聚氰胺酚醛纤维(PMF),考察了温度对PMF合成的影响。以扫描电子显微镜(SEM)、透射电子显微镜(TEM)、N2吸脱附和傅里叶变换红外(FTIR)光谱等表征了PMF的形貌和结构,并采用体积法测定不同温度下CO2和N2在PMF上的单组分吸附平衡等温线。结果表明,在393K下合成的PMF具有较大的比表面积(64m^2/g)和较高的CO2吸附量(1.83mmol/g,298K、118kPa)。穿透柱实验表明,在298K、200-600kPa,CO2-N2混合气在PMF上均可实现有效分离。将PMF在873K下,N2、H2及水蒸气等多种气氛中进行后处理,其比表面积和微孔孔容均显著增加,其中,在15%H2O气氛中处理后,样品CO2吸附量提高至2.83mmol/g(298K、118kPa)。 展开更多
关键词 三聚氰胺 纳米纤维 CO2吸附 穿透柱 富氮纳米炭纤维
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Porous Electrospun Nanofiber from Biomass-Based Polyester Blends of Polylactic Acid and Polybutylene Succinate 预览
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作者 Manisara Phiriyawirut Kanokwan Sarapat +1 位作者 Sutasinee Sirima Anrasee Prasertchol 《高分子化学期刊(英文)》 2019年第1期1-15,共15页
We studied the electrospinning process of the blend of polylactic acid (PLA) and polybutylene succinate (PBS). The blend PLA/PBS ratio 95/5, 90/10, 85/15 and 80/20 wt% were prepared by dissolved in mixture of solvent ... We studied the electrospinning process of the blend of polylactic acid (PLA) and polybutylene succinate (PBS). The blend PLA/PBS ratio 95/5, 90/10, 85/15 and 80/20 wt% were prepared by dissolved in mixture of solvent between dichloromethane (DCM) and N, N-dimethylformamide (DMF) at ratio 3/1. The suitable condition for electrospun of the blend was 17% wt concentration, 16 kV and 18 cm projection distance. The round fiber with pore on the surface was observed. Increasing content of PBS in the blend impact to the diameter of fibril decreased from 1350, 1290, 1210 and 1170 nm, respectively;while the pore on the surface changes from circle to oval shape. Regarding the thermal properties, blending of PBS increases the glass transition temperature (Tg) of PLA without affect to the melting temperature (Tm) of the electrospun nanofibers. The best tensile properties of PLA/PBS nanofibers were achieved at blend ratio of 95/5, and Young’s modulus is increased comparing to those of the pure electrospun fibers. 展开更多
关键词 ELECTROSPINNING Polymer BLEND PLA PBS NANOFIBER
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聚己内酯/壳聚糖核壳结构纤维引导组织再生膜的制备及表征 预览
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作者 邓丹 李玉宝 +4 位作者 黄金会 孙富华 左奕 李吉东 王亚宁 《化工进展》 EI CAS CSCD 北大核心 2019年第3期1501-1508,共8页
高性能的引导组织再生膜是牙周引导组织再生术成功的关键,静电纺丝法因可仿生制备类细胞外基质结构,在引导组织再生膜研制方面显示出巨大潜力。本研究通过同轴静电纺丝法,以聚己内酯(PCL)为核层,壳聚糖(CS)为壳层,制备核壳结构的纳米纤... 高性能的引导组织再生膜是牙周引导组织再生术成功的关键,静电纺丝法因可仿生制备类细胞外基质结构,在引导组织再生膜研制方面显示出巨大潜力。本研究通过同轴静电纺丝法,以聚己内酯(PCL)为核层,壳聚糖(CS)为壳层,制备核壳结构的纳米纤维,并用香草醛对制备的纤维膜进行交联。利用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、力学测试及细胞培养等手段对制备的纤维膜进行形貌、内部结构、化学组成、力学性能和细胞相容性表征。结构分析表明本研究成功制备了核壳结构的PCL-CS纤维膜。力学测试和亲疏水性测试结果表明交联后的纤维膜具有较好的耐水性和力学性能,断裂强度高出文献报道值近两倍;体外细胞培养结果显示MG-63细胞能在交联后的纤维膜上黏附和持续增殖,表明纤维膜具有较好的细胞相容性,在引导组织再生领域有较好的应用前景。 展开更多
关键词 聚己内酯 壳聚糖 核-壳结构 纳米纤维 引导组织再生膜
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Investigating the structural effect of electrospun nano-fibrous polymeric films on water vapor transmission
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作者 Seyed Jalil Poormohammadian Parviz Darvishi Abdol Mohammad Ghalambor Dezfuli 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第1期100-109,共10页
Electrospun polymers have many applications in the industry.However, the structure of these polymers has been less widely considered by researchers.In this work, the structural effect of electrospun and casted films o... Electrospun polymers have many applications in the industry.However, the structure of these polymers has been less widely considered by researchers.In this work, the structural effect of electrospun and casted films of polyacrylonitrile(PAN) and polyvinylidene fluoride(PVDF) polymers on water vapor transmission were investigated.Sorption of water vapor was measured at 35, 60 and 80 ℃ and different relative humidities.The diffusion coefficients were calculated based on mass changes of the polymer sample.The water vapor transmission rate(WVTR) was also measured at 35 ℃ and 90% relative humidity.The results indicated that electrospun nano-fibrous polymers(ESNPs) absorb much higher water vapor compared to non-porous casted polymers.The interaction of water molecules with mentioned polymers was investigated based on Flory-Huggins theory.The Flory-Huggins interaction parameter of electrospun films was less than casted films, suggesting much better interaction of water molecules with electrospun films.It was also found that electrospun films have anomalous kinetic behavior and do not obey the Fickian diffusion model.Finally, it was revealed that ESNPs show less resistance to water vapor transmission and they are good candidates for the applications of water vapor separation using membranes. 展开更多
关键词 Water vapor transmission POLYMER structure NANOFIBER ELECTROSPINNING POROUS layer
碳酸乙烯酯对聚己内酯/冰乙酸电纺纤维的影响 预览 被引量:1
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作者 张宇 张祥林 +3 位作者 章万乘 李文超 欧昊 周锦鸽 《工程塑料应用》 CAS CSCD 北大核心 2019年第2期14-19,共6页
在聚己内酯(PCL)/冰乙酸(GAC)溶液体系中加入低毒低挥发性溶剂碳酸乙烯酯(EC),采用静电纺丝法成功制备纳米纤维,采用扫描电子显微镜研究了不同EC浓度对制得的纤维形貌和直径的影响。结果表明,当溶液中PCL质量分数为20%,EC体积分数从0%... 在聚己内酯(PCL)/冰乙酸(GAC)溶液体系中加入低毒低挥发性溶剂碳酸乙烯酯(EC),采用静电纺丝法成功制备纳米纤维,采用扫描电子显微镜研究了不同EC浓度对制得的纤维形貌和直径的影响。结果表明,当溶液中PCL质量分数为20%,EC体积分数从0%变化到9%时,纳米纤维数量增加,平均直径逐渐变小;当EC体积分数从9%变化到15%时,微米纤维或珠串状纤维数量开始增加,平均直径逐渐变大。对比研究了EC体积分数为9%的溶液与未加EC的溶液的纺丝稳定性,同时对比研究了由这两种溶剂分别制备的纳米纤维膜和微米纤维膜的结构和性能。结果表明,PCL/GAC/EC溶液体系黏度可在24h内保持稳定,满足连续电纺要求;X射线衍射测试结果表明两种纤维膜结晶构型一致,只是结晶度和晶粒大小有所区别;傅里叶变换红外光谱分析结果表明EC对PCL的化学结构没有影响;与微米纤维膜相比,纳米纤维膜的比表面积提高了362.6%,平均孔直径有所减小,接触角有所增大;纳米纤维膜的拉伸断裂应力稍大但断裂应变明显小于微米纤维膜。 展开更多
关键词 聚己内酯 冰乙酸 碳酸乙烯酯 溶剂 静电纺丝 纳米纤维
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金属离子对组装多肽的形貌调控研究
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作者 樊禹 李香丹 王磊 《分子科学学报:中英文版》 CAS 北大核心 2019年第4期287-291,共5页
设计合成了1种可形变多肽纳米材料,其多肽序列为BP-KLVFF-SWTLYTPSGQSK,并对其能否在Ca2+存在下进行形貌转化进行了研究.通过吸收光谱和荧光光谱验证了随着水含量的增加,多肽分子的聚集程度增加.通过透射电子显微镜和动态光散射验证了在... 设计合成了1种可形变多肽纳米材料,其多肽序列为BP-KLVFF-SWTLYTPSGQSK,并对其能否在Ca2+存在下进行形貌转化进行了研究.通过吸收光谱和荧光光谱验证了随着水含量的增加,多肽分子的聚集程度增加.通过透射电子显微镜和动态光散射验证了在Ca2+溶液中纳米颗粒转变为纳米纤维,没有Ca2+的存在下,纳米颗粒在水溶液中粒径逐渐减小,透射电子显微镜图像观察到以纳米颗粒的形式存在.从而验证了Ca2+对多肽的形貌调控效果. 展开更多
关键词 多肽 纳米颗粒 纳米纤维 形貌转化
空气过滤用静电纺PAN纳米纤维膜的制备及性能研究 预览
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作者 吴薇 陈思 郭虹 《国际纺织导报》 2019年第5期1-4,6,7,8,10共8页
利用单针头纺丝法制备用于防雾霾口罩滤芯层的静电纺聚丙烯腈(PAN)纳米纤维膜。分析了PAN质量分数、纺丝电压及接收距离对静电纺纳米纤维膜性能的影响,并通过正交试验,获得纺制高性能纳米纤维膜的优化方案如下:PAN质量分数为14%,纺丝电... 利用单针头纺丝法制备用于防雾霾口罩滤芯层的静电纺聚丙烯腈(PAN)纳米纤维膜。分析了PAN质量分数、纺丝电压及接收距离对静电纺纳米纤维膜性能的影响,并通过正交试验,获得纺制高性能纳米纤维膜的优化方案如下:PAN质量分数为14%,纺丝电压为20kV,接收距离为15cm。 展开更多
关键词 空气过滤 防雾霾 静电纺丝 纳米纤维
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静电纺PA6/CTS/LiCl纳米纤维膜的制备研究
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作者 潘思博 王娇娜 +3 位作者 方亦男 王其智 李凤飞 李从举 《化工新型材料》 CAS CSCD 北大核心 2019年第6期93-96,101共5页
采用静电纺丝技术制备聚酰胺6(PA6)/壳聚糖(CTS)/氯化锂(LiCl)纳米纤维膜,考察了CTS、PA6及LiCl添加量对纳米纤维膜形貌、直径分布的影响。通过场发射扫描电子显微镜、傅里叶变换红外光谱仪对纳米纤维膜的微观形貌及表面官能团进行分析... 采用静电纺丝技术制备聚酰胺6(PA6)/壳聚糖(CTS)/氯化锂(LiCl)纳米纤维膜,考察了CTS、PA6及LiCl添加量对纳米纤维膜形貌、直径分布的影响。通过场发射扫描电子显微镜、傅里叶变换红外光谱仪对纳米纤维膜的微观形貌及表面官能团进行分析。结果表明:在PA6添加量为1.8g、CTS添加量为0.3g、LiCl添加量为0.12g的条件下,纺丝效果最佳,纤维平均直径为103nm。傅里叶变换红外光谱分析表明PA6/CTS/LiCl纳米纤维膜具有PA6和CTS的特征吸收峰,PA6/CTS/LiCl纳米纤维膜有望作为滤膜材料使用。 展开更多
关键词 静电纺丝 纳米纤维 壳聚糖 氯化锂
Hippocampal Neuron-Derived Extracellular Matrix Coated Nanofibrous Scaffold for Neural Tissue Engineering 预览
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作者 郜增 刘月 +4 位作者 王冲 李月霞 施剑敏 汤赋匀 娄向新 《东华大学学报:英文版》 EI CAS 2019年第5期431-436,共6页
The aim of this study is to prepare poly-L-lactide(PLLA)electrospun nanofibrous scaffolds coated with hippocampal neuron-derived extracellular matrix(N-ECM)and construct a novel neural tissue engineering scaffold.Neon... The aim of this study is to prepare poly-L-lactide(PLLA)electrospun nanofibrous scaffolds coated with hippocampal neuron-derived extracellular matrix(N-ECM)and construct a novel neural tissue engineering scaffold.Neonatal rat hippocampal neurons were seeded on PLLA nanofibers,and then decellularized to derive a cell-free extracellular matrix loaded N-ECM/PLLA modified scaffolds.The morphology and ingredients of N-ECM/PLLA were observed by scanning electron microscopy(SEM)and immunofluorescence staining respectively,and the cytocompatibility of the composite scaffolds was characterized by cell count kit-8(CCK-8)assay.The N-ECM was clearly identified loading on scaffolds when being imaged via SEM and immunofluorescence staining results showed that the N-ECM was made up of fibronectin and laminin.Most importantly,compared with tissue culture polystyrene and pure scaffolds,N-ECM/PLLA scaffolds could effectively facilitate the proliferation of rat adrenal neuroma cells(PC12 cells),indicating their better cell compatibilities.Based on the combination of N-ECM and PLLA biomaterials,the present study has fabricated a unique and versatile neural tissue engineering scaffold,offering a new thought for future neural tissue engineering. 展开更多
关键词 tissue engineering extracellular matrix electrospun nanofiber hippocampal neuron
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TiO2和UV531对PAN防紫外线纳米纤维的影响分析
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作者 王西贤 刘呈坤 +1 位作者 张志华 贾琳 《上海纺织科技》 北大核心 2019年第5期5-8,15共5页
为了研究不同防紫外线添加剂对PAN纳米纤维的影响,在聚合物PAN溶液中分别加入了TiO2与UV531,利用静电纺丝技术制备了PAN仪等仪器对比分析了纯PAN、PAN/UV531、PAN严重,表面会有TiO2颗粒聚集;红外光谱图显示PAN说明TiO2与UV531的加入并... 为了研究不同防紫外线添加剂对PAN纳米纤维的影响,在聚合物PAN溶液中分别加入了TiO2与UV531,利用静电纺丝技术制备了PAN仪等仪器对比分析了纯PAN、PAN/UV531、PAN严重,表面会有TiO2颗粒聚集;红外光谱图显示PAN说明TiO2与UV531的加入并未改变聚合物PAN的分子基团结构;添加防紫外线的TiO2与UV531后,PAN纳米纤维膜的防紫外线性能有了卓越的提升,添加剂的含量越高,紫外线防护性能越好,对UVA和UVB的透射率越小。 展开更多
关键词 紫外线吸收剂 静电纺丝 聚丙烯腈 TIO2 UV531 纳米纤维 紫外线防护性能
聚吡咯/聚烯烃弹性体纳米纤维压力传感器的制备及性能应用 预览
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作者 刘翠 钟卫兵 王栋 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第6期94-99,共6页
以原位聚合法制备导电聚吡咯/聚烯烃弹性体(PPy/POE)纳米纤维浆料,并利用模版复制法获得表面具有微阵列结构的导电纳米纤维膜。研究了导电纳米纤维膜表面结构对传感器灵敏度的影响,探究了投入Py单体与POE弹性纳米纤维质量比和导电纳米... 以原位聚合法制备导电聚吡咯/聚烯烃弹性体(PPy/POE)纳米纤维浆料,并利用模版复制法获得表面具有微阵列结构的导电纳米纤维膜。研究了导电纳米纤维膜表面结构对传感器灵敏度的影响,探究了投入Py单体与POE弹性纳米纤维质量比和导电纳米纤维膜的厚度对传感器性能的影响。结果表明,对导电纳米纤维膜作表面结构化处理可大幅提高传感器的灵敏度。当Py单体与纳米纤维质量比为1∶1,导电纳米纤维膜厚度为48μm时,纳米纤维基压力传感器灵敏度可达39.7kPa^-1,施加应力和撤除应力时的响应时间分别为10ms和12ms。通过探究传感器组件结构与性能之间的关系,得到了最优传感器组件结构参数与压力传感器性能。 展开更多
关键词 聚吡咯 弹性纳米纤维 表面结构 厚度 压力传感器
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GO掺杂PVDF纳米纤维的制备及应用
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作者 赵明慧 喻红芹 《上海纺织科技》 北大核心 2019年第9期22-24,63共4页
静电纺纳米纤维具有比表面积大、纤维直径细、孔隙率高等优点,广泛应用于空气过滤、防水透湿等领域。采用静电纺丝技术,通过在聚偏氟乙烯(PVDF)中掺杂不同质量分数的氧化石墨烯(GO)来制备PVDF/GO复合纳米纤维,并利用扫描电镜对复合纳米... 静电纺纳米纤维具有比表面积大、纤维直径细、孔隙率高等优点,广泛应用于空气过滤、防水透湿等领域。采用静电纺丝技术,通过在聚偏氟乙烯(PVDF)中掺杂不同质量分数的氧化石墨烯(GO)来制备PVDF/GO复合纳米纤维,并利用扫描电镜对复合纳米纤维膜的形貌结构进行表征测试。结果显示:当纺丝电压为15 kV时, PVDF纳米纤维形貌较为规整,纤维粗细分布均匀,平均直径为537.61 nm;在PVDF机制中掺杂0.2%GO时,出现了较多的超细纳米纤维,粗细纤维分布较为明显;当纳米纤维膜具有一定厚度时,显示了较好的过滤效率,其过滤效率和过滤阻力分别为99.84%和44.38 Pa。由此可见,所制备的GO掺杂PVDF纳米纤维在空气过滤领域有较大的应用前景。 展开更多
关键词 纳米纤维 静电纺丝 聚偏氟乙烯 氧化石墨烯 过滤效率 过滤阻力
静电纺丝技术在药物递送系统中的应用
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作者 李京晗 潘昊 +3 位作者 陈建亭 路思羽 于江 潘卫三 《沈阳药科大学学报》 CAS CSCD 北大核心 2019年第1期85-90,共6页
目的综述静电纺丝技术在黏膜、缓控释及伤口敷料与组织修复再生领域中的应用,为其进一步应用于医药领域提供依据。方法查阅相关文献,对其在口腔黏膜、眼部黏膜和阴道黏膜,以及pH敏感释放及缓控释中的应用进行归纳总结。结果静电纺丝技... 目的综述静电纺丝技术在黏膜、缓控释及伤口敷料与组织修复再生领域中的应用,为其进一步应用于医药领域提供依据。方法查阅相关文献,对其在口腔黏膜、眼部黏膜和阴道黏膜,以及pH敏感释放及缓控释中的应用进行归纳总结。结果静电纺丝技术有助于提高药物的溶解度和生物利用度,芯-壳结构等静电纺丝纤维技术的发展使得其应用于药物的缓释、控释递送过程成为可能。静电纺丝纤维可以增大细胞接触面积,当使用生物相容性良好的高分子材料时,非常适合细胞的增殖。结论在不同学科的相互支持下,静电纺丝技术在医药领域有了更多的发展,应用前景广阔。 展开更多
关键词 静电纺丝 药物递送系统 纳米纤维
纳米纤维固相萃取高效液相色谱法测定人血浆中川芎嗪含量 预览
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作者 邱新峰 《蚌埠医学院学报》 CAS 2019年第6期778-781,共4页
目的:建立纳米纤维固相萃取高效液相色谱法检测人血浆中川芎嗪含量。方法:样品经1%氨水稀释3倍,用活化后的PCAX型复合阴离子交换纳米纤维固相萃取柱净化富集,用去离子水淋洗,以50μL甲醇洗脱,取20μL进样检测。以甲醇1%冰醋酸水溶液(45... 目的:建立纳米纤维固相萃取高效液相色谱法检测人血浆中川芎嗪含量。方法:样品经1%氨水稀释3倍,用活化后的PCAX型复合阴离子交换纳米纤维固相萃取柱净化富集,用去离子水淋洗,以50μL甲醇洗脱,取20μL进样检测。以甲醇1%冰醋酸水溶液(45∶55,V/V)为流动相在岛津ODS-2色谱柱(250 mm×4.6 mm,5μm)上进行分离,流速1.0 mL/min,检测波长295 nm。结果:该方法的线性范围为0.01~2.00μg/mL,检出限为0.003μg/mL,回收率为94.88%~103.11%,相对标准偏差为2.6%~4.3%。结论:该方法操作简单,具有样品需要量少、灵敏度高等优点,可用于人血浆中川芎嗪的含量测定。 展开更多
关键词 川芎嗪 高效液相色谱 纳米纤维 固相萃取 人血浆
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Thermal Conductivity and Tensile Properties of Carbon Nanofiber-Reinforced Aluminum-Matrix Composites Fabricated via Powder Metallurgy: Effects of Ball Milling and Extrusion Conditions on Microstructures and Resultant Composite Properties
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作者 Fumio Ogawa Shuji Yamamoto Chitoshi Masuda 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第5期573-584,共12页
Carbon nanofiber(CNF)-reinforced aluminum-matrix composites were fabricated via ball milling and spark plasma sintering(SPS), SPS followed by hot extrusion and powder extrusion. Two mixing conditions of CNF and alumin... Carbon nanofiber(CNF)-reinforced aluminum-matrix composites were fabricated via ball milling and spark plasma sintering(SPS), SPS followed by hot extrusion and powder extrusion. Two mixing conditions of CNF and aluminum powder were adopted: milling at 90 rpm and milling at 200 rpm. After milling at 90 rpm, the mixed powder was sintered using SPS at 560℃. The composite was then extruded at 500℃ at an extrusion ratio of 9. Composites were also fabricated via powder extrusion of powder milled at 200 rpm and 550℃ with an extrusion ratio of 9(R9) or 16(R16). The thermal conductivity and tensile properties of the resultant composites were evaluated. Anisotropic thermal conductivity was observed even in the sintered products. The anisotropy could be controlled via hot extrusion. The thermal conductivity of composites fabricated via powder extrusion was higher than those fabricated using other methods. However, in the case of specimens with a CNF volume fraction of 4.0%, the thermal conductivity of the composite fabricated via SPS and hot extrusion was the highest. The highest thermal conductivity of 4.0% CNF-reinforced composite is attributable to networking and percolation of CNFs. The effect of the fabrication route on the tensile strength and ductility was also investigated. Tensile strengths of the R9 composites were the highest. By contrast, the R16 composites prepared under long heating duration exhibited high ductility at CNF volume fractions of 2.0% and 5.0%. The microstructures of composites and fracture surfaces were observed in detail, and fracture process was elucidated. The results revealed that controlling the heating and plastic deformation during extrusion will yield strong and ductile composites. 展开更多
关键词 Al composite Carbon NANOFIBER Ball MILLING Hot EXTRUSION Microstructure and performance
静电纺丝法制备高性能富锂锰基正极材料
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作者 牛棒棒 李建玲 +1 位作者 刘艳莹 张勇杰 《稀有金属与硬质合金》 CAS CSCD 北大核心 2019年第5期55-59,共5页
为解决富锂锰基材料首圈效率低,倍率性能差的缺陷,采用静电纺丝法制备了Li1.2[Mn0.54Ni0.13Co0.13]O2富锂锰基正极材料。实验结果表明,通过静电纺丝法制备的纳米纤维材料具有三维立体结构和更大的比表面积,提高反应活性并降低了锂离子... 为解决富锂锰基材料首圈效率低,倍率性能差的缺陷,采用静电纺丝法制备了Li1.2[Mn0.54Ni0.13Co0.13]O2富锂锰基正极材料。实验结果表明,通过静电纺丝法制备的纳米纤维材料具有三维立体结构和更大的比表面积,提高反应活性并降低了锂离子传导阻抗,从而使得材料的倍率性能和放电容量得到了改善。在5 C倍率下,纺丝纤维放电比容量为175 mA·h/g,而沉淀颗粒仅为154 mA·h/g。此外,首圈效率和放电容量也得到了提升,从72.87%提升至81.93%,以上表明静电纺丝法制备的富锂锰基材料具有更优异的性能。 展开更多
关键词 富锂锰基正极材料 静电纺丝 纳米纤维 共沉淀 三维结构
Drug-eluting fully covered self-expanding metal stent for dissolution of bile duct stones in vitro 预览
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作者 Chao Huang Xiao-Bo Cai +3 位作者 Li-Li Guo Xiao-Sheng Qi Qiang Gao Xin-Jian Wan 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第26期3370-3379,共10页
BACKGROUND The treatment of difficult common bile duct stones(CBDS)remains a big challenge around the world.Biliary stenting is a widely accepted rescue method in patients with failed stone extraction under endoscopic... BACKGROUND The treatment of difficult common bile duct stones(CBDS)remains a big challenge around the world.Biliary stenting is a widely accepted rescue method in patients with failed stone extraction under endoscopic retrograde cholangiopancreatography.Fully covered self-expanding metal stent(FCSEMS)has gained increasing attention in the management of difficult CBDS.AIM To manufacture a drug-eluting FCSEMS,which can achieve controlled release of stone-dissolving agents and speed up the dissolution of CBDS.METHODS Customized covered nitinol stents were adopted.Sodium cholate(SC)and disodium ethylene diamine tetraacetic acid(EDTA disodium,EDTA for short)were used as stone-dissolving agents.Three different types of drug-eluting stents were manufactured by dip coating(Stent I),coaxial electrospinning(Stent II),and dip coating combined with electrospinning(Stent III),respectively.The drugrelease behavior and stone-dissolving efficacy of these stents were evaluated in vitro to sort out the best manufacturing method.And the selected stonedissolving stents were further put into porcine CBD to evaluate their biosecurity.RESULTS Stent I and Stent II had obvious burst release of drugs in the first 5 d while Stent III presented controlled and sustainable drug release for 30 d.In still buffer,the final stone mass-loss rate of each group was 5.19%±0.69%for naked FCSEMS,20.37%±2.13%for Stent I,24.57%±1.45%for Stent II,and 33.72%±0.67%for Stent III.In flowing bile,the final stone mass-loss rate of each group was 5.87%±0.25%for naked FCSEMS,6.36%±0.48%for Stent I,6.38%±0.37%for Stent II,and 8.15%±0.27%for Stent III.Stent III caused the most stone mass-loss no matter in still buffer or in flowing bile,which was significantly higher than those of other groups(P<0.05).In vivo,Stent III made no difference from naked FCSEMS in serological analysis(P>0.05)and histopathological examination(P>0.05).CONCLUSION The novel SC and EDTA-eluting FCSEMS is efficient in diminishing CBDS in vitro.When conventional endoscopic techniques fa 展开更多
关键词 Common BILE duct stone DRUG-ELUTING STENT Fully COVERED self-expanding metal STENT ELECTROSPINNING NANOFIBER film
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Polyoxometalate-loaded Nanocellulose Sponge as a Novel Catalyst for the Regioselective Hydroboration of Phenylacetylene 预览
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作者 GuoQing Yang CongCong Zhang +5 位作者 BiJia Wang ZhiPing Mao Hong Xu Yi Zhong XueLing Feng XiaoFeng Sui 《造纸与生物质材料:英文版》 2019年第2期1-9,共9页
In this work,an amino-modified cellulose nanofiber sponge was prepared and used as a support for polyoxometalate(POM)catalysts with a high loading efficiency.Fourier transform infrared spectroscopy,thermogravimetric a... In this work,an amino-modified cellulose nanofiber sponge was prepared and used as a support for polyoxometalate(POM)catalysts with a high loading efficiency.Fourier transform infrared spectroscopy,thermogravimetric analysis,and energy-dispersive X-ray spectroscopy revealed that an Anderson-type POM,(NH4)4[CuMo6O18(OH)6]·5H2O was successfully immobilized on the sponge based on electrostatic interactions.Morphological analysis indicated that the POM-loaded sponge retained its porous structure and that the POM was homogeneously distributed on the sponge walls.The POM-loaded sponge exhibited excellent mechanical properties by recovering 79.9%of its original thickness following a 60%compression strain.The POM-loaded sponge was found to effectively catalyze the hydroboration of phenylacetylenes,yielding excellent conversion and regioselectivity of up to 96%and 99%,respectively.Its catalytic activity remained unchanged after five reuse cycles.These findings represent a scalable strategy for immobilizing POMs on porous supports. 展开更多
关键词 cellulose nanofiber POLYOXOMETALATES CATALYST immobilization HYDROBORATION heterogeneous CATALYST
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Eu(TTA)2(phen)MAA/PVA纳米复合纤维的制备及发光性能 预览
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作者 张爱琴 王芷 +2 位作者 胥伟 王永超 贾虎生 《太原理工大学学报》 CAS 北大核心 2019年第6期798-805,共8页
采用自制的铕配合物Eu(TTA)2(phen)MAA,将其分散到聚乙烯醇PVA中,再通过静电纺丝技术制得一维复合纳米荧光纤维Eu(TTA)2(phen)MAA/PVA.扫描电子显微镜(SEM)对纤维的微观形貌的表征结果表明,复合纤维的表面光滑,平均直径约为150 nm,红外... 采用自制的铕配合物Eu(TTA)2(phen)MAA,将其分散到聚乙烯醇PVA中,再通过静电纺丝技术制得一维复合纳米荧光纤维Eu(TTA)2(phen)MAA/PVA.扫描电子显微镜(SEM)对纤维的微观形貌的表征结果表明,复合纤维的表面光滑,平均直径约为150 nm,红外和紫外光谱分析证实配合物Eu(TTA)2(phen)MAA均匀分散在Eu(TTA)2(phen)MAA/PVA复合纤维中。荧光光谱表明,不同配合物含量的纤维在365 nm波长激发下均表现出明亮的红光发射,当配合物Eu(TTA)2(phen)MAA质量分数为8%时,纳米复合纤维的发光强度最大,为同比例掺杂型聚合物荧光粉发光强度的2倍。热重分析表明,Eu(TTA)2(phen)MAA/PVA纳米纤维的初始分解温度为254℃,比配合物的初始分解温度高27℃,热稳定性能提高。Eu(TTA)2(phen)MAA/PVA纳米复合纤维的荧光寿命为0.643 ms,高于配合物的荧光寿命(0.538 ms). 展开更多
关键词 掺杂 静电纺丝 纳米纤维 发光性能
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