英语翻译Magnetic nanoparticles are of great interest for researchersfrom a wide range of disciplines,including magneticfluids,catalysis,biotechnology/biomedicine,[4] magneticresonance imaging,data storage,and environmentalremediation.While a numb

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英语翻译Magnetic nanoparticles are of great interest for researchersfrom a wide range of disciplines,including magneticfluids,catalysis,biotechnology/biomedicine,[4] magneticresonance imaging,data storage,and environmentalremediation.While a numb

英语翻译Magnetic nanoparticles are of great interest for researchersfrom a wide range of disciplines,including magneticfluids,catalysis,biotechnology/biomedicine,[4] magneticresonance imaging,data storage,and environmentalremediation.While a numb
英语翻译
Magnetic nanoparticles are of great interest for researchers
from a wide range of disciplines,including magnetic
fluids,catalysis,biotechnology/biomedicine,[4] magnetic
resonance imaging,data storage,and environmental
remediation.While a number of suitable methods have
been developed for the synthesis of magnetic nanoparticles of
various different compositions,successful application of such
magnetic nanoparticles in the areas listed above is highly
dependent on the stability of the particles under a range of
different conditions.In most of the envisaged applications,the
particles perform best when the size of the nanoparticles is
below a critical value,which is dependent on the material but
is typically around 10–20 nm.Then each nanoparticle
becomes a single magnetic domain and shows superparamagnetic
behavior when the temperature is above the so-called
blocking temperature.Such individual nanoparticles have a
large constant magnetic moment and behave like a giant
paramagnetic atom with a fast response to applied magnetic
fields with negligible remanence (residual magnetism) and
coercivity (the field required to bring the magnetization to
zero).These features make superparamagnetic nanoparticles
very attractive for a broad range of biomedical applications
because the risk of forming agglomerates is negligible at room
temperature.
However,an unavoidable problem associated with particles
in this size range is their intrinsic instability over longer
periods of time.Such small particles tend to form agglomerates
to reduce the energy associated with the high surface area
to volume ratio of the nanosized particles.Moreover,naked
metallic nanoparticles are chemically highly active,and are
easily oxidized in air,resulting generally in loss of magnetism
and dispersibility.For many applications it is thus crucial to
develop protection strategies to chemically stabilize the
naked magnetic nanoparticles against degradation during or
after the synthesis.These strategies comprise grafting of or
coating with organic species,including surfactants or polymers,
or coating with an inorganic layer,such as silica or
carbon.It is noteworthy that in many cases the protecting
shells not only stabilize the nanoparticles,but can also be used
for further functionalization,for instance with other nanoparticles
or various ligands,depending on the desired
application.

英语翻译Magnetic nanoparticles are of great interest for researchersfrom a wide range of disciplines,including magneticfluids,catalysis,biotechnology/biomedicine,[4] magneticresonance imaging,data storage,and environmentalremediation.While a numb
磁性纳米粒子的研究人员的极大兴趣
从学科门类齐全,包括磁
液体,催化,生物技术/生物医药,[4]磁
磁共振成像,数据存储和环境
整治.虽然有一些合适的方法
已开发了磁性纳米颗粒的合成
各种不同的成分,这样的成功应用
在上述领域的磁性纳米粒子的高度
对粒子的稳定性依赖于下一个范围
不同的条件.在最设想的应用,
表现最佳的颗粒时,颗粒大小
低于临界值,这是在物质依赖,但
一般约为10-20纳米.然后每个纳米粒子
成为一个单一的,并显示超顺磁畴
行为当温度高于所谓的
截止温度.这种个别颗粒有
大恒定磁场的时刻,像一个巨大的
具有快速反应顺磁性原子的应用
领域的微不足道剩磁(剩磁)和
矫顽力(需要把磁化到外地
零).这些特性使得超顺磁性纳米粒子
非常有吸引力的一个医学领域的应用范围广泛
因为形成结块的风险可以忽略不计,在室温
温度.
然而,一个不可避免的问题与粒子
在这个尺寸范围是他们内在的不稳定性在更长
期间的时间.这样容易形成小颗粒团聚
减少与高表面积相关的能源
以纳米级颗粒的体积比.此外,赤裸
金属纳米粒子的化学性质非常活跃,并
在空气中易氧化,造成的损失一般在磁
和分散性.对于许多应用,因此它的关键
制定保护战略,化学稳定
赤裸裸的磁性纳米粒子对降解过程中或
之后的合成.这些战略包括嫁接或
涂料用有机物种,包括表面活性剂或聚合物,
或涂层与无机层,如硅或
碳.值得注意的是,在许多情况下,保护
贝壳不仅稳定的纳米颗粒,但也可以用于
为进一步功能化与其他粒子的实例,
或者,根据不同的配体所希望的
申请.