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991.
A novel organic–inorganic hybrid nanocatalyst, Ag nanoparticles supported poly[N-(3-Trimethoxy silyl)propyl]aniline (Ag@PTMSPA), was prepared by a simple one-step method. X-ray diffraction analysis, field emission transmission electron microscopy and X-ray photo electron spectroscopy reveal the coexistence of Ag nanoparticles (average size ∼ 10 nm) and PTMSPA in Ag@PTMSPA. N2 adsorption–desorption experiments provide the textural properties of the catalyst, such as surface area (86.6 m2/g), pore volume (1.3 × 10− 1 cm3/g) and pore size (4.2 nm). UV–visible spectroscopy was used to follow the kinetics of reduction of 4-nitrophenol (4-NP) by sodium borohydride (NaBH4) in the presence of Ag@PTMSPA catalyst.  相似文献   
992.
用一步法直接合成了表面氨基化修饰的Fe3O4纳米颗粒(NH2-MION),通过双功能团试剂戊二醛将牛血清白蛋白(BSA)固定在NH2-MION表面,将BSA-MION用于苦瓜提取液中活性成分的筛选,利用气相色谱-质谱联用技术鉴定出了3种与BSA作用较强的活性成分。  相似文献   
993.
无机液相源模板法制备TiO_2纳米线及光催化性能   总被引:1,自引:0,他引:1  
以无机盐TiOSO4为原料,采用多孔氧化铝模板技术,通过液相的溶胶-电泳法,制备出直径为30~70nm的TiO2纳米线。试验发现,通过对多孔氧化铝模板孔径形貌的设计,可以对纳米线的结构进行调控。由无机盐原料制备出的纳米线与有机盐原料不同,以硫酸氧钛为原料制备的无机溶胶纳米线,纯TiO2就表现出较高的可见光催化性能,这是锐钛矿纳米晶的表面分布着部分未分解结晶的过氧钛酸黄色络合物所致,它可以吸收可见光使TiO2光敏化而具有可见光活性。  相似文献   
994.
KH570用量对纳米SiO_2接枝改性的影响   总被引:3,自引:0,他引:3  
以乙醇和水混合液作为分散介质,采用硅烷偶联剂KH570对纳米二氧化硅(Nano-SiO2)进行接枝改性,制备了KH570接枝改性纳米SiO(2Nano-SiO2-g-KH570)。采用红外光谱、粒度分析及亲油化度测试,研究了KH570用量对Nano-SiO2改性效果的影响。结果表明,以乙醇和水混合液为分散介质,KH570可以对Nano-SiO2进行接枝改性;KH570用量对Nano-SiO2-g-KH570的粒径、粒径分布及亲油化度有明显的影响:KH570用量为5%时,Nano-SiO2-g-KH570的粒径最小,为103nm,粒径分布较窄,亲油化度为32%。  相似文献   
995.
Solid-state polymer electrolytes (SPEs) have attracted significant attention owing to their improvement in high energy density and high safety performance. However, the low lithium-ion conductivity of SPEs at room temperature restricts their further application in lithium-ion batteries (LIBs). Herein, we propose a novel poly (ethylene oxide) (PEO)-based nanocomposite polymer electrolytes by blending boron-containing nanoparticles (BNs) in the PEO matrix (abbreviated as: PEO/BNs NPEs). The boron atom of BNs is sp2-hybridized and contains an empty p-orbital that can interact with the anion of lithium salt, promoting the dissociation of the lithium salts. In addition, the introduction of the BNs could reduce the crystallinity of PEO. And thus, the ionic conductivity of PEO/BNs NPEs could reach as high as 1.19 × 10−3 S cm−1 at 60°C. Compared to the pure PEO solid polymer electrolyte (PEO SPEs), the PEO/BNs NPEs showed a wider electrochemical window (5.5 V) and larger lithium-ion migration number (0.43). In addition, the cells assembled with PEO/BNs NPEs exhibited good cycle performance with an initial discharge capacity of 142.5 mA h g−1 and capacity retention of 87.7% after 200 cycles at 2 C (60°C).  相似文献   
996.
Elastomeric nanoparticles (ENPs) are rubber nanoparticles that have different effects than carbon black (CB) when added to rubber composites. To further understand the effects of ENPs on rubber composites, the morphologies, viscoelasticity, mechanical properties, and interactions with rubber were carefully studied. The results revealed that ENPs and CB differed in terms of their dispersion states and reinforcing effects on rubber. The addition of ENPs can reduce the free chain ends of rubber composites, which helps reduce the rolling resistance, making it a possible way to develop energy-saving tires. Compared with current techniques for lowering the free chain ends of vulcanisates, it is easier and simpler to add ENPs to rubber composites. The results also show that ENPs and CB had a synergistic effect on rubber reinforcement. The optimal ENP content, considering the vulcanisate characteristics, was approximately 10 phr.  相似文献   
997.
《Ceramics International》2023,49(12):20118-20126
When nanomaterials with antibacterial properties were sent to the infected area, it was predicted that infection and related complications could be prevented. The nanoparticles can be designed to possess magnetic and luminescence (magneto-luminescent) properties to be effectively targeted and localized at the infection foci without dispersing into the body. Simultaneously, the magneto-luminescent characteristic of particles allows visualization and confirmation of localized particles at the desired area. In this regard, there are no studies on the use of antibacterial magneto-luminescent bioactive glass for orthopedic applications and the treatment of orthopedic device-related infections. In this study, antibacterial magneto-luminescent 58S bioactive glasses were synthesized by the modified Stöber using coupled with a layer-by-layer assembly approach to possess core/shell particle morphology. SPION/Bioactive glass nanoparticles had an average size of 50 nm and displayed superparamagnetic behavior. While the saturation magnetization value (σs) of the undoped 58S sample was 25.32 emu/g, that of the co-doped sample (2% Eu, 2% Zn) was 21.74 emu/g; this showed that the doping slightly reduced the magnetization value. Europium (Eu) doping of SPION/Bioactive glass nanoparticles induced characteristic red emission originating from Eu emissions belonging to 5D07FJ (J = 1–4) transitions and the strongest peak was at 612 nm (electric-dipole transition, 5D07F2). Color chromaticity coordinates confirmed emission in the red region. XPS spectrum revealed the existence of Eu and Zn dopant elements in 58S bioactive glass. After soaking characteristic peaks at 31.74° and 45.43° belonging to the hexagonal hydroxyapatite phase were detected in the XRD data, confirming the SEM images. 2% Eu doped SPION/Bioactive glass nanoparticles had the highest osteoblast viability up to 7 days in vitro, while doping the samples with 2% zinc did not yield bone cell viability as high as the Eu doped ones. Importantly, Eu doped SPION/Bioactive glass nanoparticles inhibited gram-positive Staphylococcus aureus (S. aureus) and gram-negative Escherichia coli (E. coli) growth up to 48 h in vitro. The results showed that Eu doping of SPION/Bioactive glass nanoparticles increased osteoblast viability and inhibited bacterial growth, while possessing superparamagnetic properties and exhibiting red luminescence.  相似文献   
998.
为改善聚偏氟乙烯(PVDF)膜的抗污性能,以聚乙二醇2000接枝的GO/TiO2(PEG/GO/TiO2)纳米复合材料为添加剂,通过非溶剂诱导沉淀相分离法制备了一系列PEG/GO/TiO2/PVDF复合超滤膜。采用FTIR、SEM和接触角测试仪对其结构和形貌进行了表征,采用超滤法评价其纯水通量和抗污性能。结果表明,当PEG/GO/TiO2纳米复合材料质量分数为0.60%时,制备的PEG/GO/TiO2/PVDF复合超滤膜(记为0.60%PEG/GO/TiO2/PVDF)表现出最佳的亲水性和抗污性能,其接触角比PVDF膜下降8.2°,总孔隙率增加13.40%,PEG/GO/TiO2纳米复合材料在PVDF膜中分散较均匀。在0.08 MPa的工作压力下,0.60%PEG/GO/TiO2/PVDF的纯水通量高达282.44 L/(m2·h),对腐植酸溶液的过滤通量为131.96 L/(m2...  相似文献   
999.
The blooming requirement of high-performance energy storage systems has aroused the thirst for advanced energy storage materials. As a high capacity anode, however, the application of NiO nanoparticles (NiO NPs) is hindered by intractable issues of dramatic volume change, intrinsic low electronic conductivity, and severe aggregation tendency during lithiation/delithiation. Herein, a polydopamine (PDA) assisted bi-functionalization strategy for fabricating of PDA@NiO-CNT composites for fast and durable lithium storage is reported. In this composite, CNTs intertwine to form a network to ensure sufficient electrolyte infiltration and act as a highly conductive system to motivate fast charge transmission. The strong binding affinity of PDA facilitates bonding between NiO NPs and CNTs, which not only forms uniform and flexible PDA coating but also ensures homogeneous distribution of NiO NPs on CNTs network. Therefore, the bi-functional modified PDA@NiO-CNT electrode possesses high conductivity, alleviates volume change and aggregation of NiO NPs during cycling, achieves a reversible capacity of 1326 mAh g−1 at 100 mA g−1, a rate capability of 215 mAh g−1 at 2000 mA g−1 and a cycling stability with 78% capacity retention after 250 cycles. This bi-functional modification approach manifests its prospective potential for architecting other electrode materials toward high-performance electrochemical devices.  相似文献   
1000.
构建基于磁荧光纳米材料的免疫层析试纸模式,弥补现在免疫层析技术的不足,为更灵敏的免疫学快速检测提供技术支撑。以呕吐毒素(deoxynivalenol,DON)为靶标,采用溶剂热法制备羧基修饰的超顺磁颗粒,碳二亚胺法将磁颗粒、绿色荧光蛋白及DON单克隆抗体进行偶联,一步法制备磁荧光抗体探针,以DON人工抗原(DON-BSA)为检测线建立磁荧光免疫层析试纸。同时用胶体金标记DON单克隆抗体,以DON-BSA为检测线建立胶体金免疫层析试纸;制备的磁荧光抗体探针具有很好的磁性、荧光特性及抗体反应性,基于该探针成功制备了DON磁荧光免疫层析试纸,该试纸回归方程为y=-0.562x+0.921,R2=0.990,IC50为5.611 ng/mL,检出限为1.089 ng/mL;制备了DON胶体金免疫层析试纸,该试纸裸眼检测灵敏度为500 ng/mL;定量检测回归方程为y=-0.543x+1.485,R2=0.991,IC50为65.16 ng/mL,检出限为11.94 ng/mL。DON磁荧光免疫层析试纸的灵敏度是胶体金免疫层析试纸的10.96 倍。本实验建立的磁荧光免疫层析试纸模式可以同时实现样品的富集及荧光信号检测,提高检测灵敏度,并成功用于DON的检测,为磁荧光纳米颗粒广泛应用于免疫层析领域提供参考。  相似文献   
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