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101.
Zahra Mohammadpour Zahra Sadat Hashemi Fatemeh Malekian Jebeli Sahel Ghasemzadeh Esfandyar Askari Mandana Akbary-Yekta Ramin Sarrami-Forooshani 《Particle & Particle Systems Characterization》2021,38(12):2100162
Iron oxychloride (FeOCl) is known for reactive oxygen species (ROS) generation through Fenton chemistry. The activity of FeOCl is preserved in the slightly acidic pH value of the tumor microenvironment (pH 6.5−6.9). Such property can be advantageous in biobased systems, where ROS generation can be modulated in slightly acidic conditions, which is characteristic of the solid tumor microenvironment. In the present study, BSA-stabilized FeOCl nanosheets (NSs) are synthesized and characterized by transmission electron microscope, Fourier transform infrared spectroscopy, zeta potential analysis, dynamic light scattering, and UV–vis spectroscopy. The morphology of the nanoparticles is flake-like, and their hydrodynamic diameter is around 200 nm. MTT, apoptosis assay, and trypan blue staining evaluate the toxicity of FeOCl NSs toward the 4T1 cell line. It is found that the toxicity of the NSs is higher in physiological conditions of solid tumors (pH 6.5, H2O2 100 × 10−6 m ) than in the conditions of healthy organs (pH 7.4). Specifically, cancer cells are in their late apoptotic stage by more than eight times higher at pH 6.5 than pH 7.4. The toxicity results are in agreement with the in vitro catalytic assay of the NSs. Therefore, the FeOCl NSs can be the building blocks for constructing chemodynamic therapy agents. 相似文献
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利用水热法制备得到NaYbF4:0.01%Tm3+,20%Eu3+上转换材料,利用X射线衍射分析、扫描电子显微镜及光谱测试技术分别对其进行了结构、形貌以及光谱性质的表征。在980 nm近红外激光激发下,得到了Eu3+的可见到紫外范围的上转换荧光发射。分析表明:共掺杂NaYbF4纳米材料中Tm3+到Eu3+离子的能量传递对布居Eu3+离子的激发态能级,获得Eu3+的上转换发光起着至关重要的作用。另外,在实验中首次获得了Eu3+对应于3P0→7Fj (j=0,1,2)能级跃迁的上转换光发射。 相似文献
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105.
Xiangrong Xu Lee Koetzner Jamie Boulet Harry Maselli Jessica Beyenhof Gary Grover 《Biomedical chromatography : BMC》2009,23(9):973-979
A simple and sensitive analytical method using liquid chromatography–tandem mass spectrometry (LC/MS/MS) for determination of acetylsalicylic acid (aspirin, ASA) and its major metabolite, salicylic acid (SA), in animal plasma has been developed and validated. Both ASA and SA in plasma samples containing potassium fluoride were extracted using acetonitrile (protein precipitation) with 0.1% formic acid in it. 6‐Methoxysalicylic acid was used as the internal standard (IS). The compounds were separated on a reversed‐phase column. The multiple reaction monitoring mode was used with ion transitions of m/z 178.9 → 136.8, 137.0 → 93.0 and 167.0 → 123.0 for ASA, SA and IS, respectively. The lower limits of quantification for ASA and SA were 3 and 30 ng/mL, respectively. The developed method was successfully applied for the evaluation of pharmacokinetics of ASA and SA after p.o. and i.v. administration of 1 mg/kg to rats. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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采用化学气相沉积方法,在无催化剂的条件下,通过改变衬底位置在Si(100)衬底上制备出了高取向的磷掺杂ZnO纳米线和纳米钉.测试结果表明,当衬底位于反应源上方1.5 cm处时,所制备的样品为钉状结构,而当衬底位于反应源下方1 cm处时样品为线状结构.对不同形貌磷掺杂ZnO纳米结构的生长机理进行了研究.此外,在ZnO纳米结构的低温光致发光谱中观测到了一系列与磷掺杂相关的受主发光峰.还对磷掺杂ZnO纳米结构/n-Si异质结I-V曲线进行了测试,结果表明,该器件具有良好的整流特性,纳米线和纳米钉异质结器件的开启电压分别为4.8和3.2 V. 相似文献
108.
This article outlines state-of-the-art energy technologies, including production and storage, available to us through semiconductor nanomaterials. The nanostructure growth processes have been illustrated in detail, with emphasis on the latest developments in hierarchical and radial-composition modulated nanostructures. On the energy efficiency and generation part, light-emitting diodes, photovoltaics, photoelectrochemistry, thermoelectric, and fuel cells have been discussed. In the energy storage part, supercapacitors and lithium batteries have been discussed. 相似文献
109.
在光电子学应用中,器件性能主要取决于半导体纳米材料中的光生载流子动力学过程. 但是,受反应速率、材料表面积、材料组成等多种因素影响,描述其中的动力学过程非常具有挑战性. 模拟光生载流子动力学过程可以通过绝热分子动力学方法实现,即求解包含非绝热耦合项的含时薛定谔方程. 在众多绝热分子动力学方法中,面跳跃方法出色地平衡了计算精度和计算成本,因而成为描述半导体纳米材料中不同非绝热过程间竞争的有力工具,已被用来模拟材料中的超快动力学过程和其他复杂效应,如Janus过渡金属二硫族化合物范德华异质结中的电荷分离. 本综述通过介绍该领域代表性的理论及实验工作,阐述了光生载流子对半导体纳米材料性能的重要影响,以及面跳跃方法在描述其动力学行为中的重要作用. 由于日趋复杂的材料体系对理论工作提出了巨大的挑战,本综述重点介绍了最近用于模拟这些复杂材料的一些开创性的新方法,包括高精度的电子结构方法和与之相结合的绝热分子动力学方法. 相似文献
110.
Akshay Mathkar T. N. Narayanan Lawrence B. Alemany Paris Cox Patrick Nguyen Guanhui Gao Patricia Chang Rebeca Romero‐Aburto Sendurai A. Mani P. M. Ajayan 《Particle & Particle Systems Characterization》2013,30(3):266-272
The richly functionalized basal plane bonded to polar organic moieties makes graphene oxide (GO) innately hydrophilic. Here, a methodology to synthesize fluorinated graphene oxide by oxidizing the basal plane of fluorinated graphite, allowing for tunable hydrophobicity of GO, is reported. Fluorine exists as tertiary alkyl fluorides covalently bonded to graphitic carbons, and using magic‐angle spinning (MAS) 13C NMR as a primary tool chemical structures for the two types of synthesized fluorinated graphene oxides (FGOs) with significantly different fluorine contents are proposed. The low surface energy of the C–F bond drastically affects GO's wetting behavior, leading to amphiphobicity in its highly fluorinated form. Ease of solution processing enables the fabrication of inks that are spray‐painted on various porous/non‐porous substrates. These coatings maintain amphiphobicity for solvents with surface tensions down to 59 dyn/cm, thus bypassing existing lithographic means to create similar surfaces. The approach towards fluorinating GO and fabricating graphene‐based surfaces with tunable wettability opens the path towards unique, accessible, carbon‐based amphiphobic coatings. 相似文献