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| The term phase transition (or phase change) is most commonly used to describe transitions between solid, liquid, and gaseous states of matter, as well as plasma in rare cases. A phase of a thermodynamic system and the states of matter have uniform physical properties. During a phase transition of a given medium, certain properties of the medium change, often discontinuously, as a result of the change of external conditions, such as temperature, pressure, or others. For example, a liquid may become gas upon heating to the boiling point, resulting in an abrupt change in volume. The measurement of the external conditions at which the transformation occurs is termed the phase transition. Phase transitions commonly occur in nature and are used today in many technologies. | | The term phase transition (or phase change) is most commonly used to describe transitions between solid, liquid, and gaseous states of matter, as well as plasma in rare cases. A phase of a thermodynamic system and the states of matter have uniform physical properties. During a phase transition of a given medium, certain properties of the medium change, often discontinuously, as a result of the change of external conditions, such as temperature, pressure, or others. For example, a liquid may become gas upon heating to the boiling point, resulting in an abrupt change in volume. The measurement of the external conditions at which the transformation occurs is termed the phase transition. Phase transitions commonly occur in nature and are used today in many technologies. |
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− | '''<font color="#ff8000"> 相变Phase transition (or phase change)</font>'''一词常用于描述物质固态,液态和气态之间的转变,在极少数情况下还涉及到等离子体。热力学系统的相和物质的状态一样,均具有统一的物理特性。由于外部条件(例如温度,压力或其他)的变化,在给定介质的相变过程中,它的某些属性通常会发生不连续地变化。例如,液体在加热到沸点的时候可能会变成气体,导致体积大小突然改变。'''<font color="#32CD32">当这种转变发生时,外部条件的度量称为相变</font>'''。相变通常发生在自然界,不过如今越来越多地被用于科技行业。 | + | '''<font color="#ff8000"> 相变Phase transition (or phase change)</font>'''一词常用于描述物质固态,液态和气态之间的转变,在极少数情况下还涉及到等离子体。热力学系统的相和物质的状态均具有统一的物理特性。由于外部条件(例如温度,压力或其他)的变化,在给定介质的相变过程中,介质的某些属性会发生通常是不连续的变化。例如,液体在被加热到沸点时可能会变成气体,导致体积大小突然发生改变。'''<font color="#32CD32">当这种转变发生时,外部条件的度量称为相变</font>'''。相变通常发生在自然界,不过如今越来越多地被用于科技行业。 |
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| *The transitions between the solid, liquid, and gaseous phases of a single component, due to the effects of temperature and/or [[pressure]]: | | *The transitions between the solid, liquid, and gaseous phases of a single component, due to the effects of temperature and/or [[pressure]]: |
− | 由于温度和/或压力的影响,单个成分物质的固态,液态和气态之间会产生相互变化: | + | 由于温度和/或压力的影响,单个成分物质在固态,液态和气态之间的转换: |
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| [[文件:物质的相变big.png|500px|thumb|centre|参见蒸汽压和相图]] | | [[文件:物质的相变big.png|500px|thumb|centre|参见蒸汽压和相图]] |
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| * A [[eutectic]] transformation, in which a two-component single-phase liquid is cooled and transforms into two solid phases. The same process, but beginning with a solid instead of a liquid is called a [[eutectoid]] transformation. | | * A [[eutectic]] transformation, in which a two-component single-phase liquid is cooled and transforms into two solid phases. The same process, but beginning with a solid instead of a liquid is called a [[eutectoid]] transformation. |
− | '''<font color="#ff8000"> 共晶转变Eutectic transformation</font>'''指的是一类互溶液体(由两种不同成分组成的单相液体)经过冷却后,转变成为两个不同的固相。同样的过程,由一类固相开始转变成为两个不同的固相,则称为共析转变。 | + | '''<font color="#ff8000"> 共晶转变Eutectic transformation</font>''',即互溶液体(由两种不同成分组成的单相液体)经过冷却后,转变成为两个不同的固相。同样的过程,由一类固相开始转变成为两个不同的固相,则称为'''<font color="#ff8000"> 共析转变 Eutectoid transformation</font>'''。 |
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| * A [[metastable]] to equilibrium phase transformation. A metastable polymorph which forms rapidly due to lower surface energy will transform to an equilibrium phase given sufficient thermal input to overcome an energetic barrier. | | * A [[metastable]] to equilibrium phase transformation. A metastable polymorph which forms rapidly due to lower surface energy will transform to an equilibrium phase given sufficient thermal input to overcome an energetic barrier. |
− | 由于较低的表面能而迅速形成的'''<font color="#ff8000"> 亚稳多晶体Metastable polymorph</font>'''会逐渐趋向一种平衡相,前提是需要足够的热输入以克服能量位垒。
| + | <font color="#32CD32">平衡态的亚稳转换</font>。由于较低的表面能而迅速形成的'''<font color="#ff8000"> 亚稳多晶体Metastable polymorph</font>''',在有足够的热输入以克服能量位垒时,会逐渐转换为一种平衡相。 |
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| * A [[peritectic]] transformation, in which a two-component single-phase solid is heated and transforms into a solid phase and a liquid phase. | | * A [[peritectic]] transformation, in which a two-component single-phase solid is heated and transforms into a solid phase and a liquid phase. |
− | '''<font color="#ff8000"> 包晶转变Peritectic transformation</font>''',指的是一类单相固体(包含两种不同成分)经过加热后转变为一种固相和一种液相的过程。 | + | '''<font color="#ff8000"> 包晶转变Peritectic transformation</font>''',即包含两种不同成分的单相固体经过加热后转变为一种固相和一种液相的过程。 |
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| * A [[spinodal decomposition]], in which a single phase is cooled and separates into two different compositions of that same phase. | | * A [[spinodal decomposition]], in which a single phase is cooled and separates into two different compositions of that same phase. |
− | '''<font color="#ff8000"> 亚稳相分解Spinodal decomposition</font>''',指的是一个单相经过冷却后分离为同相的两种不同成分的物质。 | + | '''<font color="#ff8000"> 亚稳相分解Spinodal decomposition</font>''',即一个单相经过冷却后分离为同相的两种不同成分的物质。 |
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| * Transition to a [[mesophase]] between solid and liquid, such as one of the "[[liquid crystal]]" phases. | | * Transition to a [[mesophase]] between solid and liquid, such as one of the "[[liquid crystal]]" phases. |
− | 在固体和液体之间过渡的'''<font color="#ff8000"> 中间相Mesophase</font>''',例如“'''<font color="#ff8000"> 液晶Liquid crystal</font>'''”相之一。
| + | 向在固体和液体之间过渡的'''<font color="#ff8000"> 中间相Mesophase</font>''',例如一种“'''<font color="#ff8000"> 液晶Liquid crystal</font>'''”相,的转换。 |
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| * The transition between the [[ferromagnetism|ferromagnetic]] and [[paramagnetism|paramagnetic]] phases of [[magnet]]ic materials at the [[Curie point]]. | | * The transition between the [[ferromagnetism|ferromagnetic]] and [[paramagnetism|paramagnetic]] phases of [[magnet]]ic materials at the [[Curie point]]. |
− | 磁性材料在'''<font color="#ff8000"> 居里点Curie point</font>'''(居里温度)时,'''<font color="#ff8000"> 铁磁Ferromagnetism</font>'''和'''<font color="#ff8000"> 顺磁Paramagnetism</font>'''相之间的转变。 | + | 磁性材料在'''<font color="#ff8000"> 居里点Curie point</font>'''(居里温度)时,在'''<font color="#ff8000"> 铁磁Ferromagnetism</font>'''和'''<font color="#ff8000"> 顺磁Paramagnetism</font>'''相之间的转变。 |
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| * The transition between differently ordered, [[ANNNI model|commensurate]] or [[commensurability (mathematics)|incommensurate]], magnetic structures, such as in cerium [[antimonide]]. | | * The transition between differently ordered, [[ANNNI model|commensurate]] or [[commensurability (mathematics)|incommensurate]], magnetic structures, such as in cerium [[antimonide]]. |
− | 在各种有序,'''<font color="#ff8000"> 相称Commensurate</font>'''或'''<font color="#ff8000"> 不相称Incommensurate</font>'''的磁性结构(如'''<font color="#ff8000"> 锑化铈Antimonide</font>'''中)之间的转变。
| + | 在不同方式组织的,'''<font color="#ff8000"> 相称Commensurate</font>'''或'''<font color="#ff8000"> 不相称Incommensurate</font>'''的磁性结构(如在'''<font color="#ff8000"> 锑化铈Antimonide</font>'''中)之间的转变。 |
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| * The [[martensitic transformation]] which occurs as one of the many phase transformations in carbon steel and stands as a model for [[displacive phase transformations]]. | | * The [[martensitic transformation]] which occurs as one of the many phase transformations in carbon steel and stands as a model for [[displacive phase transformations]]. |
− | '''<font color="#ff8000"> 马氏体转变Martensitic transformation</font>'''是碳钢的众多相变之一,是典型的'''<font color="#ff8000"> 位移相变Displacive phase transformations</font>''' | + | '''<font color="#ff8000"> 马氏体转变Martensitic transformation</font>''',碳钢的众多相变之一,也是典型的'''<font color="#ff8000"> 位移相变Displacive phase transformations</font>''' |
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| * Changes in the [[crystallographic]] structure such as between [[Allotropes of iron|ferrite]] and [[austenite]] of iron. | | * Changes in the [[crystallographic]] structure such as between [[Allotropes of iron|ferrite]] and [[austenite]] of iron. |
− | 晶体结构的变化,例如铁在不同温度,不同处理方式下'''<font color="#ff8000"> 铁素体Ferrite</font>'''铁素体Ferrite和'''<font color="#ff8000"> 奥氏体Austenite</font>'''之间的转变。
| + | 晶体结构的变化,例如铁在'''<font color="#ff8000"> 铁素体Ferrite</font>'''和'''<font color="#ff8000"> 奥氏体Austenite</font>'''之间的转变。 |
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| * Order-disorder transitions such as in alpha-[[titanium aluminide]]s. | | * Order-disorder transitions such as in alpha-[[titanium aluminide]]s. |
− | 有序到无序的转变,例如α-钛铝化物。
| + | 有序到无序的转变,在α-钛铝化物中发生着这种转变。 |
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| * The emergence of [[superconductivity]] in certain metals and ceramics when cooled below a critical temperature. | | * The emergence of [[superconductivity]] in certain metals and ceramics when cooled below a critical temperature. |
− | 当冷却到临界温度以下时,某些金属和陶瓷会出现'''<font color="#ff8000"> 超导Superconductivity</font>'''现象。
| + | 当冷却到临界温度以下时,某些金属和陶瓷中'''<font color="#ff8000"> 超导Superconductivity</font>'''现象的出现。 |
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− | * The transition between different molecular structures ([[Polymorphism (materials science)|polymorphs]], [[allotropy|allotropes]] or [[polyamorphism|polyamorphs{{not a typo}}]]), especially of solids, such as between an [[amorphous solid|amorphous]] structure and a [[crystal]] structure, between two different crystal structures, or between two amorphous structures. | + | * The transition between different molecular structures ([[Polymorphism (materials science)|polymorphs]], [[allotropy|allotropes]] or [[polyamorphism|polyamorphs]]), especially of solids, such as between an [[amorphous solid|amorphous]] structure and a [[crystal]] structure, between two different crystal structures, or between two amorphous structures. |
| 不同分子结构('''<font color="#ff8000"> 同质多形体Polymorphs</font>''','''<font color="#ff8000"> 同素异形体Allotropes</font>'''或'''<font color="#ff8000"> 非晶多形体Polyamorphs</font>''')之间的转变,特别是固体之间的转变,例如非晶结构和晶体结构之间,两种不同晶体结构之间或两种非晶结构之间的转变。 | | 不同分子结构('''<font color="#ff8000"> 同质多形体Polymorphs</font>''','''<font color="#ff8000"> 同素异形体Allotropes</font>'''或'''<font color="#ff8000"> 非晶多形体Polyamorphs</font>''')之间的转变,特别是固体之间的转变,例如非晶结构和晶体结构之间,两种不同晶体结构之间或两种非晶结构之间的转变。 |
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| * The [[Symmetry breaking|breaking of symmetries]] in the laws of physics during the early history of the universe as its temperature cooled. | | * The [[Symmetry breaking|breaking of symmetries]] in the laws of physics during the early history of the universe as its temperature cooled. |
− | 早期的宇宙随着温度的降温,物理学定律的'''<font color="#ff8000"> 对称性破裂Breaking of symmetries</font>'''。
| + | 早期的宇宙中随着降温而发生的,物理学定律的'''<font color="#ff8000"> 对称性破裂Breaking of symmetries</font>'''。 |
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| * [[Isotope fractionation]] occurs during a phase transition, the ratio of light to heavy isotopes in the involved molecules changes. When [[water vapor]] condenses (an [[equilibrium fractionation]]), the heavier water isotopes (18O and 2H) become enriched in the liquid phase while the lighter isotopes (16O and 1H) tend toward the vapor phase. | | * [[Isotope fractionation]] occurs during a phase transition, the ratio of light to heavy isotopes in the involved molecules changes. When [[water vapor]] condenses (an [[equilibrium fractionation]]), the heavier water isotopes (18O and 2H) become enriched in the liquid phase while the lighter isotopes (16O and 1H) tend toward the vapor phase. |
− | '''<font color="#ff8000"> 同位素分馏Isotope fractionation</font>'''发生在相变过程中,所涉及分子中的轻同位素与重同位素的比率会发生变化。当水蒸气冷凝(平衡分馏)时,较重的水同位素(18O和2H)在液相中富集,而较轻的同位素(16O和1H)则趋向于气相。 | + | '''<font color="#ff8000"> 同位素分馏Isotope fractionation</font>''',发生在相变过程中,所涉及分子的轻同位素与重同位素的比率发生变化。当水蒸气冷凝(<font color="#32cd32">平衡分馏</font>)时,较重的水同位素(18O和2H)在液相中富集,而较轻的同位素(16O和1H)则趋向于气相。 |
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| Phase transitions occur when the thermodynamic free energy of a system is non-analytic for some choice of thermodynamic variables (cf. phases). This condition generally stems from the interactions of a large number of particles in a system, and does not appear in systems that are too small. It is important to note that phase transitions can occur and are defined for non-thermodynamic systems, where temperature is not a parameter. Examples include: quantum phase transitions, dynamic phase transitions, and topological (structural) phase transitions. In these types of systems other parameters take the place of temperature. For instance, connection probability replaces temperature for percolating networks. | | Phase transitions occur when the thermodynamic free energy of a system is non-analytic for some choice of thermodynamic variables (cf. phases). This condition generally stems from the interactions of a large number of particles in a system, and does not appear in systems that are too small. It is important to note that phase transitions can occur and are defined for non-thermodynamic systems, where temperature is not a parameter. Examples include: quantum phase transitions, dynamic phase transitions, and topological (structural) phase transitions. In these types of systems other parameters take the place of temperature. For instance, connection probability replaces temperature for percolating networks. |
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− | 当一个系统的热力学自由能对于某些热力学变量(参见相)选择不解析时,就会发生相变。这种情况通常是由于系统中存在大量粒子相互作用,如果系统太小,则不太会出现。值得注意的是,相变的发生和定义同样可以针对于非热力学系统,并且不将温度作为参数。例如:量子相变,动态相变和拓扑(结构)相变。在这些类型的系统中,其他参数代替了温度。例如,连接概率代替'''<font color="#ff8000"> 渗滤网络Percolating networks</font>'''的温度。
| + | 当一个系统的热力学自由能对于某些热力学变量(参见相)选择<font color="#32cd32">不解析</font>时,就会发生相变。这种情况通常是由于系统中存在大量粒子相互作用,如果系统太小,则不会出现。值得注意的是,相变的发生和定义同样可以针对于温度不是参数的非热力学系统。例如:量子相变,动态相变和拓扑(结构)相变。在这些类型的系统中,其他参数代替了温度。例如,在'''<font color="#ff8000"> 渗滤网络Percolating networks</font>'''中,连接概率代替了温度。 |
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| At the phase transition point (for instance, boiling point) the two phases of a substance, liquid and vapor, have identical free energies and therefore are equally likely to exist. Below the boiling point, the liquid is the more stable state of the two, whereas above the gaseous form is preferred. | | At the phase transition point (for instance, boiling point) the two phases of a substance, liquid and vapor, have identical free energies and therefore are equally likely to exist. Below the boiling point, the liquid is the more stable state of the two, whereas above the gaseous form is preferred. |
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− | 在相变点(例如,沸点)下,一种物质的两个相(液体和蒸气)具有相同的自由能,因此它们可以同时存在。而当温度低于沸点时,液体在两者中状态更稳定,因此相比较气态更趋近于液态存在。
| + | 在相变点(如沸点)下,一种物质的两个相(液体和蒸气)具有相同的自由能,因此它们有相同的可能性存在。而当温度低于沸点时,液态在两者中状态更稳定,同时,温度高于沸点时,气态更占优。 |
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| It is sometimes possible to change the state of a system diabatically (as opposed to adiabatically) in such a way that it can be brought past a phase transition point without undergoing a phase transition. The resulting state is metastable, i.e., less stable than the phase to which the transition would have occurred, but not unstable either. This occurs in superheating, supercooling, and supersaturation, for example. | | It is sometimes possible to change the state of a system diabatically (as opposed to adiabatically) in such a way that it can be brought past a phase transition point without undergoing a phase transition. The resulting state is metastable, i.e., less stable than the phase to which the transition would have occurred, but not unstable either. This occurs in superheating, supercooling, and supersaturation, for example. |
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− | 有时可以通过传热方式(注意不是绝热方式)改变系统状态,使系统状态可以通过相变点而不会经历相变。因此该系统会处于亚稳态,是指比较于相变发生过后的状态没有那么稳定,但也不是说不稳定。
| + | 有时可以通过传热方式(与绝热方式相对)改变系统状态,使系统状态可以通过相变点而不会经历相变。因此该系统会处于亚稳态(相对于相变发生过后的状态没有那么稳定,但也并非不稳定)。例如,过热、过冷以及过饱和时会发生这种现象。 |
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| == Classifications 分类== | | == Classifications 分类== |