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1.
无机纳米材料的合成是纳米科学发展的前提和基础之一。区别于传统的高温湿化学合成法,光化学方法在无机纳米材料的合成中表现出许多优点,并在近年来受到了广泛关注。本文分三个部分综述了近年来光化学方法在无机纳米材料合成中的应用,具体包括贵金属纳米材料的光化学合成与负载,半导体纳米材料的光化学合成以及表面等离子体共振诱导的各向异性金属纳米晶合成。最后,在总结光化学方法在无机纳米材料合成中体现出的优势及目前研究仍存在不足的基础上,我们对其未来可能的发展方向进行了展望。  相似文献   

2.
溶剂交换法制备一维有机纳米材料   总被引:1,自引:0,他引:1  
利用溶剂交换法制备了几种有机小分子化合物的一维纳米材料,并分别用SEM、TEM、XRD等对其结构进行了表征.分析了纳米材料的生长过程,讨论了有关的机理,并研究了其吸收光谱和荧光光谱等光物理行为.结果显示,有机纳米结构的形貌和尺寸对分子聚集体的光谱性质具有调制作用,使得它们展示出不同于溶液和体材料的优良纳米特性.  相似文献   

3.
载体材料的选择对固定化酶的性能有着至关重要的影响。纳米复合材料不仅具有纳米尺寸的特性,而且可以克服单一材料的不足,在固定化酶领域引起了广泛关注。本文就目前在固定化酶领域使用的纳米复合载体分类进行了系统的阐述,重点介绍了目前在固定化酶研究领域运用较为广泛的硅基纳米复合材料、碳基纳米复合材料和纳米纤维复合材料等材料的制备方法及不同材料对酶学性能的影响,并对这些纳米复合材料固定化酶发展前景进行了展望。  相似文献   

4.
载体材料的选择对固定化酶的性能有着至关重要的影响。纳米复合材料不仅具有纳米尺寸的特性,而且可以克服单一材料的不足,在固定化酶领域引起了广泛关注。本文就目前在固定化酶领域使用的纳米复合载体分类进行了系统的阐述,重点介绍了目前在固定化酶研究领域运用较为广泛的硅基纳米复合材料、碳基纳米复合材料和纳米纤维复合材料等材料的制备方法及不同材料对酶学性能的影响,并对这些纳米复合材料固定化酶发展前景进行了展望。  相似文献   

5.
纳米科学和碳纳米科学   总被引:4,自引:0,他引:4  
介绍了纳米材料、纳米科学、碳纳米科学的研究领域及其重要的、潜在的应用价值。  相似文献   

6.
α-Fe_2O_3空心球的水热法制备及其对苯酚的吸附性能   总被引:1,自引:0,他引:1  
以铁氰化钾、磷酸二氢铵等为反应物,采用水热法合成了α-Fe2O3空心球,并用XRD,TEM,FESEM(场发射扫描电镜)、UV-Vis和低温氮吸附脱附对其进行了表征。结果表明,α-Fe2O3空心球直径在200~560nm之间,其BET比表面积为80m2·g-1,平均孔径为8.5nm。考察了反应时间、反应物用量和反应温度等对α-Fe2O3空心球形貌和大小的影响,提出了其可能的形成机理。研究了室温下α-Fe2O3空心球吸附苯酚的性能,吸附达平衡时,其吸附苯酚的量达97mg·g-1。  相似文献   

7.
By utilizing nanomaterials including one-dimensional materials (1DMs) and two-dimensional materials (2DMs), the recent development for the determination of multiple biomolecules has been focused.  相似文献   

8.
王琳  薛卫东  廖义中 《化学教育》2007,28(10):3-4,7
介绍了纳米材料的一些应用和几种主要纳米材料(如纳米TiO2、碳纳米管、纳米铁粉等)目前已取得的部分生物效应及毒理学的研究结果;讨论了纳米材料对人体和环境带来的潜在影响,及纳米颗粒材料未来的毒性研究重点,并对纳米材料安全性进行了展望。  相似文献   

9.
双金属纳米材料作为工业上少见的一类催化剂材料,在合成过程中可通过对其组成、结构晶粒大小尺寸的调控,实现其催化性能的合理调控,因此,近年来备受催化材料化学领域科技工作者的广泛关注.随着纳米材料调控合成方面的技术进步,具有均一小尺寸可控结构的纳米材料对于制备高效催化剂材料和研究催化反应机理具有重要的意义.结合纳米技术探索开发设计新型的双金属纳米催化剂材料颇具挑战性.本文围绕双金属纳米催化剂的合成、结构及其相关催化性能,从不同的双金属纳米催化剂出发,对催化剂的性能提高、催化机理研究的若干问题和分析手段及方法在催化研究中的进展发表一点初浅认识.  相似文献   

10.
The high‐spin electronic states for lithium, sodium, and potassium four‐atom clusters were studied. In particular, we performed coupled cluster geometry optimization of the quintet state in tetrahedral geometry. The quintet state of these systems is characterized by having all the valence electron unpaired, giving rise to the so‐called no‐pair bonding. Single‐point full configuration interaction computations on the equilibrium geometries for the various clusters are also presented. The analysis of the valence orbitals in a localized representation confirms the importance of the p atomic orbitals to explain this unusual type of bond. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010  相似文献   

11.
The chiroplasmonic and chiroexcitonic platform constructed from noble metal and semiconductor nanomaterials have significantly advanced enantioselective analysis. In this paper, we summarized the exciting progresses and contributions by the peers in the field.  相似文献   

12.
The spread of antimicrobial resistance and lesser development of new antibiotics have intensified the search for new antimicrobial and diagnostic vehicles. Carbon nanomaterials (CNMs), which broadly include carbon dots, carbon nanotubes, and graphene/graphene oxide nanostructures, have emerged as promising theranostic materials exhibiting, in many instances, potent antibacterial activities and diagnostic capabilities. Ease of synthesis, tunable physicochemical properties, biocompatibility, and diverse modes of action make CNMs a powerful class of theranostic nanomaterials. This review discusses recent studies illuminating innovative new CNMs and their applications in bacterial theranostics. We particularly emphasize the relationship between the structural parameters and overall chemical properties of CNMs and their biological impact and utilization. Overall, the expanding work on the development and use of CNMs in therapeutic, sensing, and diagnostic applications in the microbial world underscores the considerable potential of these nanomaterials.  相似文献   

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15.
Studying the excited-state decay process is crucial for materials research because what happens to the excited states determines how effective the materials are for many applications, such as photoluminescence and photocatalysis. The high computational cost, however, limits the use of high-accuracy theoretical approaches for analyzing research systems containing a significant number of atoms. Time-dependent density functional theory is a practical approach to investigate the photorelaxation processes in these systems, as demonstrated in the studies of the excited-state decays of heptazine-water clusters and adenine in water described in this review. Here, we highlight the importance of conical intersections in the excited-state decay processes of these systems using the aforementioned examples. In the heptazine-water and adenine-water systems, these intersections are associated with the photocatalytic water splitting reaction, caused by a barrierless reaction called water to adenine electron-driven proton transfer. We expect the result would be helpful for researching the excited-state decays of graphitic carbon nitride materials and DNA nucleotides.  相似文献   

16.
Black phosphorus (BP), the latest addition to the family of 2D layered materials, has attracted much interest owing to potential optoelectronics, nanoelectronics, and biomedicine applications. Little is known about its toxicity, such as whether it could be as toxic as white phosphorus. In response to the possibility of BP employment into commercial products and biomedical devices, its cytotoxicity to human lung carcinoma epithelial cells (A549) was investigated. Following a 24 h exposure of the cells with different BP concentrations, cell viability assessments were conducted using water‐soluble tetrazolium salt (WST‐8) and methylthiazolyldiphenyltetrazolium bromide (MTT) assays. The toxicological effects were found to be dose‐dependent, with BP reducing cell viabilities to 48 % (WST‐8) and 34 % (MTT) at 50 μg mL?1 exposure. This toxicity was observed to be generally intermediate between that of graphene oxides and exfoliated transition‐metal dichalcogenides (MoS2, WS2, WSe2). The relatively low toxicity paves the way to utilization of black phosphorus.  相似文献   

17.
基于脂质体的纳米基因载体的研究进展   总被引:1,自引:0,他引:1  
基因治疗是指将外源基因导入目标细胞,用以修正因基因缺陷和异常导致的疾病,达到治疗疾病的目的。 外源基因在细胞中高效、持续地表达是基因治疗成功的关键,这与载体的选择息息相关。 随着科技的发展,脂质体纳米复合物作为基因载体受到人们广泛关注,其具有功能多样、易于修饰、生物相容性好、转染效率高等优点。 本文介绍了脂质体的结构特点,并对磁性纳米、金纳米、量子点、壳聚糖、上转换纳米与脂质体的复合物作为基因载体进行综述和展望。  相似文献   

18.
孔状Co_3O_4纳米片和纳米棒的选择性合成和表征(英文)   总被引:1,自引:0,他引:1  
利用两步实验选择性合成孔状Co3O4纳米片和纳米棒:首先,以Co(NO3)2·6H2O,NaOH和不同量的NH4F为原料在120℃水热6h的条件下合成了Co(OH)2-Co3O4纳米片(S1)和Co(OH)F-Co3O4纳米棒(S2);然后将所得纳米片和纳米棒在400℃时加热2h即得到多孔的Co3O4纳米片和纳米棒。所得产物用X射线衍射(XRD)、场发射扫描电子显微镜(FE-SEM)和透射电子显微镜(TEM)进行了表征。此外电化学测试表明Co3O4纳米棒的电容量比Co3O4纳米片的更大。  相似文献   

19.
在过去的几十年时间里,纳米材料已经被广泛运用到美容、食品、工程、医疗等领域.伴随着纳米材料的普及,这些材料对人体、环境展现出的毒理特征也逐渐引起了人们的关注.本文就纳米材料进入人体的传播途径(皮肤传递、呼吸和消化系统)、纳米材料对机体的毒性、纳米材料的理化性质(尺寸、形状、表面修饰、表面电荷)对纳米材料毒理性的影响以及现有的纳米毒理学研究方法进行概括与总结.该论述可为国内纳米材料研究工作者提供参考与借鉴.  相似文献   

20.
A simple scheme, with special terms and symbols useful in categorizing various nanostructures, is introduced. Using “n-D in/on m-D” composite nanomaterials where n,m ≤ 2 as examples, we illustrate how these terms and symbols can be used to represent various hetero nanostructures. This simple nomenclature system also allows a systematization of a wide variety of multi-dimensional nanocomposite heterostructures.  相似文献   

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