等离子是什么_空气净化器等离子是什么

2024-09-05 05:33:18

1.什么叫等离子？

2.等离子化解释一下怎么做到，原理是什么

3.等离子是什么

4.什么是等离子体？火焰是等离子体吗？

等离子是什么_空气净化器等离子是什么

等离子体又叫做电浆，是由部分电子被剥夺后的原子及原子被电离后产生的正负电子组成的离子化气体状物质，它广泛存在于宇宙中，常被视为是除去固、液、气外，物质存在的第四态。等离子体是一种很好的导电体，利用经过巧妙设计的磁场可以捕捉、移动和加速等离子体。等离子体物理的发展为材料、能源、信息、环境空间，空间物理，地球物理等科学的进一步发展提新的技术和工艺。

看似“神秘”的等离子体，其实是宇宙中一种常见的物质，在太阳、恒星、闪电中都存在等离子体，它占了整个宇宙的99％。现在人们已经掌握利用电场和磁场产生来控制等离子体。例如焊工们用高温等离子体焊接金属。

等离子体可分为两种：高温和低温等离子体。现在低温等离子体广泛运用于多种生产领域。例如：等离子电视，婴儿尿布表面防水涂层，增加啤酒瓶阻隔性。更重要的是在电脑芯片中的蚀刻运用，让网络时代成为现实。

高温等离子体只有在温度足够高时发生的。太阳和恒星不断地发出这种等离子体，组成了宇宙的99％。低温等离子体是在常温下发生的等离子体（虽然电子的温度很高）。低温等离子体体可以被用于氧化、变性等表面处理或者在有机物和无机物上进行沉淀涂层处理。

等离子体是物质的第四态，即电离了的“气体”，它呈现出高度激发的不稳定态，其中包括离子(具有不同符号和电荷)、电子、原子和分子。其实，人们对等离子体现象并不生疏。在自然界里，炽热烁烁的火焰、光辉夺目的闪电、以及绚烂壮丽的极光等都是等离子体作用的结果。对于整个宇宙来讲，几乎99．9％以上的物质都是以等离子体态存在的，如恒星和行星际空间等都是由等离子体组成的。用人工方法，如核聚变、核裂变、辉光放电及各种放电都可产生等离子体。分子或原子的内部结构主要由电子和原子核组成。在通常情况下，即上述物质前三种形态，电子与核之间的关系比较固定，即电子以不同的能级存在于核场的周围，其势能或动能不大。

由离子、电子以及未电离的中性粒子的集合组成，整体呈中性的物质状态．

普通气体温度升高时，气体粒子的热运动加剧，使粒子之间发生强烈碰撞，大量原子或分子中的电子被撞掉，当温度高达百万开到1亿开，所有气体原子全部电离．电离出的自由电子总的负电量与正离子总的正电量相等．这种高度电离的、宏观上呈中性的气体叫等离子体．希望这个回答对你有帮助

什么叫等离子？

等离子体

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等离子灯

放大

等离子灯

等离子体（等离子态，电浆，英文：Plasma）是一种电离的气体，由于存在电离出来的自由电子和带电离子，等离子体具有很高的电导率，与电磁场存在极强的耦合作用。等离子态在宇宙中广泛存在，常被看作物质的第四态（有人也称之为“超气态”）。等离子体由克鲁克斯在1879年发现，“Plasma”这个词，由朗廖尔在1928年最早用。

[隐藏]

o 2.1 电离

o 2.3 速率分布

* 3 参见

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常见的等离子体

等离子体是存在最广泛的一种物态，目前观测到的宇宙物质中，99%都是等离子体。

* 人造的等离子体

o 荧光灯，霓虹灯灯管中的电离气体

o 核聚变实验中的高温电离气体

o 电焊时产生的高温电弧

* 地球上的等离子体

o 火焰（上部的高温部分）

o 闪电

o 大气层中的电离层

o 极光

* 宇宙空间中的等离子体

o 恒星

o 太阳风

o 行星际物质

o 恒星际物质

o 星云

* 其它等离子体

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等离子体的性质

等离子态常被称为“超气态”，它和气体有很多相似之处，比如：没有确定形状和体积，具有流动性，但等离子也有很多独特的性质。

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电离

等离子体和普通气体的最大区别是它是一种电离气体。由于存在带负电的自由电子和带正电的离子，有很高的电导率，和电磁场的耦合作用也极强：带电粒子可以同电场耦合，带电粒子流可以和磁场耦合。描述等离子体要用到电动力学，并因此发展起来一门叫做磁流体动力学的理论。

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组成粒子

和一般气体不同的是，等离子体包含两到三种不同组成粒子：自由电子，带正电的离子和未电离的原子。这使得我们针对不同的组分定义不同的温度：电子温度和离子温度。轻度电离的等离子体，离子温度一般远低于电子温度，称之为“低温等离子体”。高度电离的等离子体，离子温度和电子温度都很高，称为“高温等离子体”。

相比于一般气体，等离子体组成粒子间的相互作用也大很多。

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速率分布

一般气体的速率分布满足麦克斯韦分布，但等离子体由于与电场的耦合，可能偏离麦克斯韦分布。

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参见

* 等离子体物理学

取自"://zh.wikipedia.org/wiki/%E7%AD%89%E7%A6%BB%E5%AD%90%E4%BD%93"

Category: 等离子体物理学

Plasma (physics)

From Wikipedia, the free encyclopedia.

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This article is about plasma in the sense of an ionized gas. For other uses of the term, such as blood plasma, see plasma (disambiguation).

A Plasma lamp, illustrating some of the more complex phenomena of a plasma, including filamentation

Enlarge

A Plasma lamp, illustrating some of the more complex phenomena of a plasma, including filamentation

In physics and chemistry, a plasma is an ionized gas, and is usually considered to be a distinct phase of matter. "Ionized" in this case means that at least one electron has been removed from a significant fraction of the molecules. The free electric charges make the plasma electrically conductive so that it couples strongly to electromagnetic fields. This fourth state of matter was first identified by Sir William Crookes in 1879 and dubbed "plasma" by Irving Langmuir in 1928, because it reminded him of a blood plasma Ref.

Contents

[hide]

* 1 Common plasmas

* 2 Characteristics

o 2.1 Plasma scaling

o 2.2 Temperatures

o 2.3 Densities

o 2.4 Potentials

* 3 In contrast to the gas phase

* 4 Complex plasma phenomena

* 5 Ultracold Plasmas

* 6 Mathematical descriptions

o 6.1 Fluid

o 6.2 Kinetic

o 6.3 Particle-in-cell

* 7 Fundamental plasma parameters

o 7.1 Frequencies

o 7.2 Lengths

o 7.3 Velocities

o 7.4 Dimensionless

o 7.5 Miscellaneous

* 8 Fields of active research

* 9 See also

* 10 External links

[edit]

Common plasmas

A solar coronal mass ejection blasts plasma throughout the Solar System. ://antwrp.gsfc.nasa.gov/apod/ap020516.html Ref & Credit

Enlarge

A solar coronal mass ejection blasts plasma throughout the Solar System. ://antwrp.gsfc.nasa.gov/apod/ap020516.html Ref & Credit

Plasmas are the most common phase of matter. The entire visible universe outside the Solar System is plasma, since all we can see are stars. Since the space between the stars is filled with a plasma, although a very sparse one (see interstellar- and intergalactic medium), essentially the entire volume of the universe is plasma. In the Solar System, the planet Jupiter accounts for most of the non-plasma, only about 0.1% of the mass and 10-15 of the volume within the orbit of Pluto. Alfvén also noted that due to their electric charge, very small grains also behe as ions and form part of a plasma (see dusty plasmas).

Commonly encountered forms of plasma include:

* Artificially produced

o Inside fluorescent lamps (low energy lighting), neon signs

o Rocket exhaust

o The area in front of a spacecraft's heat shield during reentry into the atmosphere

o Fusion energy research

o The electric arc in an arc lamp or an arc welder

o Plasma ball (sometimes called a plasma sphere or plasma globe)

* Earth plasmas

o Flames (ie. fire)

o Lightning

o The ionosphere

o The polar aurorae

* Space and astrophysical

o The Sun and other stars (which are plasmas heated by nuclear fusion)

o The solar wind

o The Interplanetary medium (the space between the planets)

o The Interstellar medium (the space between star systems)

o The Intergalactic medium (the space between galaxies)

o The Io-Jupiter flux-tube

o Accretion disks

o Interstellar nebulae

[edit]

Characteristics

The term plasma is generally reserved for a system of charged particles large enough to behe as one. Even a partially ionized gas in which as little as 1% of the particles are ionized can he the characteristics of a plasma (i.e. respond to magnetic fields and be highly electrically conductive).

In technical terms, the typical characteristics of a plasma are:

1. Debye screening lengths that are short compared to the physical size of the plasma.

2. Large number of particles within a sphere with a radius of the Debye length.

3. Mean time between collisions usually is long when compared to the period of plasma oscillations.

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Plasma scaling

Plasmas and their characteristics exist over a wide range of scales (ie. they are scaleable over many orders of magnitude). The following chart deals only with conventional atomic plasmas and not other exotic phenomena, such as, quark gluon plasmas:

Typical plasma scaling ranges: orders of magnitude (OOM)

Characteristic Terrestrial plasmas Cosmic plasmas

Size

in metres (m) 10-6 m (lab plasmas) to:

102 m (lightning) (~8 OOM) 10-6 m (spacecraft sheath) to

1025 m (intergalactic nebula) (~31 OOM)

Lifetime

in seconds (s) 10-12 s (laser-produced plasma) to:

107 s (fluorescent lights) (~19 OOM) 101 s (solar flares) to:

1017 s (intergalactic plasma) (~17 OOM)

Density

in particles per

cubic metre 107 to:

1021 (inertial confinement plasma) 1030 (stellar core) to:

100 (i.e., 1) (intergalactic medium)

Temperature

in kelvins (K) ~0 K (Crystalline non-neutral plasma[2]) to:

108 K (magnetic fusion plasma) 102 K (aurora) to:

107 K (Solar core)

Magnetic fields

in teslas (T) 10-4 T (Lab plasma) to:

103 T (pulsed-power plasma) 10-12 T (intergalactic medium) to:

107 T (Solar core)

[edit]

Temperatures

The central electrode of a plasma lamp, showing a glowing blue plasma streaming upwards. The colors are a result of the radiative recombination of electrons and ions and the relaxation of electrons in excited states back to lower energy states. These processes emit light in a spectrum characteristic of the gas being excited.

Enlarge

The defining characteristic of a plasma is ionization. Although ionization can be caused by UV radiation, energetic particles, or strong electric fields, (processes that tend to result in a non-Maxwellian electron distribution function), it is more commonly caused by heating the electrons in such a way that they are close to thermal equilibrium so the electron temperature is relatively well-defined. Because the large mass of the ions relative to the electrons hinders energy transfer, it is possible for the ion temperature to be very different from (usually lower than) the electron temperature.

The degree of ionization is determined by the electron temperature relative to the ionization energy (and more weakly by the density) in accordance with the Saha equation. If only a small fraction of the gas molecules are ionized (for example 1%), then the plasma is said to be a cold plasma, even though the electron temperature is typically several thousand degrees. The ion temperature in a cold plasma is often near the ambient temperature. Because the plasmas utilized in plasma technology are typically cold, they are sometimes called technological plasmas. They are often created by using a very high electric field to accelerate electrons, which then ionize the atoms. The electric field is either capacitively or inductively coupled into the gas by means of a plasma source, e.g. microwes. Common lications of cold plasmas include plasma-enhanced chemical vapor deposition, plasma ion doping, and reactive ion etching.

A hot plasma, on the other hand, is nearly fully ionized. This is what would commonly be known as the "fourth-state of matter". The Sun is an example of a hot plasma. The electrons and ions are more likely to he equal temperatures in a hot plasma, but there can still be significant differences.

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Densities

Next to the temperature, which is of fundamental importance for the very existence of a plasma, the most important property is the density. The word "plasma density" by itself usually refers to the electron density, that is, the number of free electrons per unit volume. The ion density is related to this by the erage charge state \langle Z\rangle of the ions through n_e=\langle Z\rangle n_i. (See quasineutrality below.) The third important quantity is the density of neutrals n0. In a hot plasma this is small, but may still determine important physics. The degree of ionization is ni / (n0 + ni).

[edit]

Potentials

Lightning is an example of plasma present at Earth's surface. Typically, lightning discharges 30 thousand amps, at up to 100 million volts, and emits light, radio wes, x-rays and even gamma rays [1]. Plasma temperatures in lightning can roach 28,000 kelvins and electron densities may exceed /m3.

Enlarge

Since plasmas are very good conductors, electric potentials play an important role. The potential as it exists on erage in the space between charged particles, independent of the question of how it can be measured, is called the plasma potential or the space potential. If an electrode is inserted into a plasma, its potential will generally lie considerably below the plasma potential due to the development of a Debye sheath. Due to the good electrical conductivity, the electric fields in plasmas tend to be very small, although where double layers are formed, the potential drop can be large enough to accelerate ions to relativistic velocities and produce synchrotron radiation such as x-rays and gamma rays. This results in the important concept of quasineutrality, which says that, on the one hand, it is a very good roximation to assume that the density of negative charges is equal to the density of positive charges (n_e=\langle Z\rangle n_i), but that, on the other hand, electric fields can be assumed to exist as needed for the physics at hand.

The magnitude of the potentials and electric fields must be determined by means other than simply finding the net charge density. A common example is to assume that the electrons satisfy the Boltzmann relation, n_e \propto e^{e\Phi/k_BT_e}. Differentiating this relation provides a means to calculate the electric field from the density: \vec{E} = (k_BT_e/e)(\nabla n_e/n_e).

It is, of course, possible to produce a plasma that is not quasineutral. An electron beam, for example, has only negative charges. The density of a non-neutral plasma must generally be very low, or it must be very small, otherwise it will be dissipated by the repulsive electrostatic force.

In astrophysical plasmas, Debye screening prevents electric fields from directly affecting the plasma over large distances (ie. greater than the Debye length). But the existence of charged particles causes the plasma to generate and be affected by magnetic fields. This can and does cause extremely complex behior, such as the generation of plasma double layers, an object that separates charge over a few tens of Debye lengths. The dynamics of plasmas interacting with external and self-generated magnetic fields are studied in the academic discipline of magnetohydrodynamics.

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In contrast to the gas phase

Plasma is often called the fourth state of matter. It is distinct from the three lower-energy phases of matter; solid, liquid, and gas, although it is closely related to the gas phase in that it also has no definite form or volume. There is still some disagreement as to whether a plasma is a distinct state of matter or simply a type of gas. Most physicists consider a plasma to be more than a gas because of a number of distinct properties including the following:

Property Gas Plasma

Electrical Conductivity Very low

Very high

1. For many purposes the electric field in a plasma may be treated as zero, although when current flows the voltage drop, though small, is finite, and density gradients are usually associated with an electric field according to the Boltzmann relation.

2. The possibility of currents couples the plasma strongly to magnetic fields, which are responsible for a large variety of structures such as filaments, sheets, and jets.

3. Collective phenomena are common because the electric and magnetic forces are both long-range and potentially many orders of magnitude stronger than gritational forces.

Independently acting species One Two or three

Electrons, ions, and neutrals can be distinguished by the sign of their charge so that they behe independently in many circumstances, hing different velocities or even different temperatures, leading to new types of wes and instabilities, among other things

Velocity distribution Maxwellian May be non-Maxwellian

Whereas collisional interactions always lead to a Maxwellian velocity distribution, electric fields influence the particle velocities differently. The velocity dependence of the Coulomb collision cross section can amplify these differences, resulting in phenomena like two-temperature distributions and run-away electrons.

Interactions Binary

Two-particle collisions are the rule, three-body collisions extremely rare. Collective

Each particle interacts simultaneously with many others. These collective interactions are about ten times more important than binary collisions.

[edit]

Complex plasma phenomena

Tycho's Supernova remnant, a huge ball of expanding plasma. Langmuir coined the name plasma because of its similarity to blood plasma, and Hannes Alfvén noted its cellular nature. Note also the filamentary blue outer shell of X-ray emitting high-speed electrons

Enlarge

Plasma may exhibit complex behiour. And just as plasma properties scale over many orders of magnitude (see table above), so do these complex features. Many of these features were first studied in the laboratory, and in more recent years, he been lied to, and recognised throughout the universe. Some of these features include:

* Filamentation, the striations or "stringy things" seen in a "plasma ball", the aurora, lightning, and nebulae. They are caused by larger current densities, and are also called magnetic ropes or plasma cables.

* Double layers, localised charge separation regions that he a large potential difference across the layer, and a vanishing electric field on either side. Double layers are found between adjacent plasmas regions with different physical characteristics, and can accelerate ions and produce synchrotron radiation (such as x-rays and gamma rays).

* Birkeland currents, a magnetic-field-aligned electric current, first observed in the Earth's aurora, and also found in plasma filaments.

* Circuits. Birkeland currents imply electric circuits, that follow Kirchhoff's circuit laws. Circuits he a resistance and inductance, and the behiour of the plasma depends on the entire circuit. Such circuits also store inductive energy, and should the circuit be disrupted, for example, by a plasma instability, the inductive energy will be released in the plasma.

* Cellular structure. Plasma double layers may separate regions with different properties such as magnetization, density, and temperature, resulting in cell-like regions. Examples include the magnetosphere, heliosphere, and heliospheric current sheet.

* Critical ionization velocity in which the relative velocity between an ionized plasma and a neutral gas, may cause further ionization of the gas, resulting in a greater influence of electomagnetic forces.

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Ultracold Plasmas

It is also possible to create ultracold plasmas, by using lasers to trap and cool neutral atoms to temperatures of 1 mK or lower. Another laser then ionizes the atoms by giving each of the outermost electrons just enough energy to escape the electrical attraction of its parent ion.

The key point about ultracold plasmas is that by manipulating the atoms with lasers, the kinetic energy of the liberated electrons can be controlled. Using standard pulsed lasers, the electron energy can be made to correspond to a temperature of as low as 0.1 K ? a limit set by the frequency bandwidth of the laser pulse. The ions, however, retain the millikelvin temperatures of the neutral atoms. This type of non-equilibrium ultracold plasma evolves rapidly, and many fundamental questions about its behiour remain unanswered. Experiments conducted so far he revealed surprising dynamics and recombination behiour that are pushing the limits of our knowledge of plasma physics.

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Mathematical descriptions

Plasmas may be usefully described with various levels of detail. However the plasma itself is described, if electric or magnetic fields are present, then Maxwell's equations will be needed to describe them. The coupling of the description of a conductive fluid to electromagnetic fields is known generally as magnetohydrodynamics, or simply MHD.

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Fluid

The simplest possibility is to treat the plasma as a single fluid governed by the Nier Stokes Equations. A more general description is the two-fluid picture, where the ions and electrons are considered to be distinct.

[edit]

Kinetic

For some cases the fluid description is not sufficient. Kinetic models inc

等离子化解释一下怎么做到，原理是什么

等离子体是物质的一种存在状态，通常物质以固态、液态、气态三种状态存在，但在一些特殊的情况下有第四种状态存在，如地球大气中电离层中的物质。等离子体状态中存在下列物质：处于高速运动状态的电子；处于激活状态的中性原子、分子、原子团（自由基）；离子化的原子、分子；未反应的分子、原子等，但物质在总体上仍保持电中性状态。

人造等离子最常用的设备有

1、常压（大气等离子清洗机）给它接入气体与能量，气体压力达到0.2mpa左右、与足够的能量，通俗来讲就是高频高压产生等离子体。再通过等离体子体轰击被清洗产品表面，以达到清洗目的。优点：（大气型快速量产）

2、（真空等离子清洗机）原理也是一样的，在真空腔体里，通过射频电源在一定的压力情况下起辉产生高能量的无序的等离子体，通过等离子体轰击被清洗产品面，以达到清洗目的。优点：（真空型精密全面）

等离子是什么

等离子的定义是“是由部分电子被剥夺后的原子及原子团被电离后产生的正负离子组成的离子化气体状物质，尺度大于德拜长度的宏观电中性电离气体，其运动主要受电磁力支配，并表现出显著的集体行为“。说白了，就是通过某些方法讲原子的外层电子从原子核附近电离，成为可以自由运动的电子和带正电的原子实。

为了做到这一点，一般有三种手段可以做到，首先是热电离，在足够的高温下，外层电子具有足够的动能可以脱离原子核的束缚（宇宙中的绝大多数可见物质都处于热电离状态，例如我们的太阳）；此外还有辐射电离和放电电离，能量的来源从热能转变为辐射能和放电，但是最终目的是一致的，使外层电子获得能量，脱离既有的轨道。

://baike.baidu/view/1277.htm

什么是等离子体？火焰是等离子体吗？

等离子是由部分电子被剥夺后的原子及原子团，被电离后产生的正负离子组成的离子化气体状物质。

等离子体（等离子）是不同于固体、液体和气体的物质第四态。物质由分子构成，分子由原子构成，原子由带正电的原子核和围绕它的、带负电的电子构成。当被加热到足够高的温度或其他原因，外层电子摆脱原子核的束缚成为自由电子，就像下课后的学生跑到操场上随意玩耍一样。

电子离开原子核，这个过程就叫做“电离”。这时，物质就变成了由带正电的原子核和带负电的电子组成的、一团均匀的“浆糊”，因此人们戏称它为离子浆，这些离子浆中正负电荷总量相等，因此它是近似电中性的，所以就叫等离子体。等离子体是由部分电子被剥夺后的原子及原子团，被电离后产生的正负离子组成的离子化气体状物质。

等离子的构成

等离子体由离子、电子以及未电离的中性粒子的集合组成，整体呈中性的物质状态。等离子体可分为两种：高温和低温等离子体。等离子体温度分别用电子温度和离子温度表示，两者相等称为高温等离子体；不相等则称低温等离子体。低温等离子体广泛运用于多种生产领域。

例如：等离子电视，婴儿尿布表面防水涂层，增加啤酒瓶阻隔性。更重要的是在电脑芯片中的蚀刻运用，让网络时代成为现实。

高温等离子体只有在温度足够高时发生的。恒星不断地发出这种等离子体，组成了宇宙的99%。低温等离子体是在常温下发生的等离子体（虽然电子的温度很高）。低温等离子体可以被用于氧化、变性等表面处理或者在有机物和无机物上进行沉淀涂层处理。

以上内容参考百度百科-等离子体

火焰一般可以看作等离子体，不过构成火焰的粒子的电离程度并不高。这将在后面进行详细讨论。那什么是等离子体呢？下面就来先为大家介绍它。

什么是等离子体？

等离子体又叫做电浆，被视为物质的第4种形态，或者称为“超气态”。简单来说就是电离了的“气体”，由离子、电子以及未电离的中性粒子组成，整体呈电中性。等离子体并不需要完全由离子构成。

等离子体属于非凝聚态，构成等离子体的粒子之间游离程度较高，粒子间的相互作用不强。至于凝聚态，就是由大量处于聚集状态的粒子构成的物态，液体和固体就是最常见的凝聚态。

等离子体并不神秘。气体通常都是由分子或原子构成的，而等离子体就是被电离（电离就是原子得到或者失去核外电子形成离子的一种过程，离子都带电）的气体。几乎所有气体都存在一定程度的电离，只是电离程度极低，因此并不能算作等离子体。并且物体要称之为等离子体，还需要具备等离子体所具备的特性，比如存在等离子体振荡、会受电磁场影响等。等离子体振荡是等离子体中的电子在惯性和离子的静电力作用下发生的简谐振动。

等离子体是宇宙中最常见的物态。宇宙中最常见的天体就是恒星，星系也是由恒星构成的，像太阳等恒星就是一个巨大的等离子体，它占了整个宇宙中物质形态的99%。自然界中的闪电就是等离子体。用人工方法，如核聚变、核裂变，也可产生等离子体。

不同等离子体在温度和密度方面差异巨大。以温度划分，等离子体可分为高温等离子体和低温等离子体。等离子体的温度分别用电子温度和离子温度表示，两者相等（或者说相差不多）则称为高温等离子体，不相等则称为低温等离子体。

最常见的等离子体是高温等离子体。处于核聚变状态的物质、电弧、闪电、极光等都是高温等离子体。高温等离子体在切割、冶炼、焊接等领域都有广泛的应用。

低温等离子体又叫做非平衡态等离子，可以存在于常温状态。辉光放电、电晕放电等现象都可以产生低温等离子体。日光灯（又叫做荧光灯）就是通过低压状态的汞蒸气通电后会发生辉光放电，并发射出紫外线，激发荧光粉发光的。在日常生活中大家耳熟能详的等离子电视，就是利用低温等离子体制成的显示器。除此之外还有等离子体涂层。

（上图为电晕放电现象）

为什么火焰属于等离子体？

火焰也是物质，是燃烧时的产物，能够发光发热。在太空中，没有重力作用，火焰会呈现为球形。

火焰的温度有高有低，不同材质燃烧时所形成的火焰，具有不同的温度。打火机火焰的温度大约在400度左右，酒精灯火焰的温度在600~700度，普通炉火的温度大约在800度左右，一般的纸张燃烧时产生的火焰温度仅为200多度。

此外，火焰又分为焰心、中焰和外焰，其中外焰由于与氧气或者氧化剂接触更充分，燃烧反应也更充分，因此温度更高。当可燃物与氧化剂接触时，温度达到着火点就会产生火焰。

一些材质燃烧时还会产生一些固体小颗粒，在热气上升的带动下夹杂在火焰中。不同的材质在燃烧时，火焰的颜色也各不相同。

一般来说温度越高，火焰中粒子的电离程度也就越高，火焰的温度一般都很高，属于高温等离子体。一些温度较低的火焰，由于电离程度太低，因此并不能完全算作等离子体，只能算是处于激发态（原子或者分子吸收能量后，被激发到高能级，尚未电离的状态）的高温气体。

上面已经说过，磁场能够影响等离子体。如果高温火焰是等离子体的话，必然会受到强磁场的影响。实验证明，火焰会受到磁场影响。

（如上图实验所示，磁场的变化能够对蜡烛火焰产生影响）

通过对等离子体有了一定的了解，相信大家也明白为什么火焰属于等离子体了。

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