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1)  vaporization heat
汽化热
1.
Experimental instrument about liquid vaporization heat using electric heating method
电热法液体汽化热实验仪的研制
2.
In this paper,based on the graph theory method,an equation was proposed for the prediction of vaporization heat of alkenes at normal boiling point.
本文以图论法为基础,提出了一个预测链烯烃常沸点汽化热的关系式,应用该式预测了25种链烯烃的常沸点汽化热,与实验值相比较的总绝对平均偏差为1。
3.
A new method for calculating the critical constants from the data of liquid density and vaporization heat at normal boiling point is presented in this paper,The method is discussed on the base of the results obtained by esti- mating the Pc and Tc values of nearly 100 kinds of representative organic matters and shows its reliability and stability.
本文提出了一个由液体比容和正常沸点下汽化热数据推算物质临界参数的新方法。
2)  heat of vaporization
汽化热
1.
A feedforward neural network was used to predict functional relationship of temperature with steam pressure and heat of vaporization of the pure material.
用前向神经网络 ,对纯物质的蒸气压和汽化热与温度的函数关系进行预测。
2.
A flow apparatus for measuring heat of vaporization of liquids under pressure up to 6 MPa,and temperature from 260 K to 480 K is developed.
建立了流动型量热法汽化热测量装置 。
3.
In this article, after the effect of waterdrops on the heat of vaporization is analyzed, the author points out that by using a glass tube with an external protective coating as a steam duct and considering the effect of waterdrops on the heat of vaporization, the accuracy can be greatly improved and errors reduced.
在水的汽化热实验中,通过分析水滴对汽化热的影响,说明采用外加保护层的玻璃管作蒸汽导管且考虑水滴对汽化热的影响,可大大提高实验精度,减小误差。
3)  evaporation heat
汽化热
1.
A modified equation for calculating evaporation heat of liquids;
一个修正的液体汽化热计算式
2.
Structure selectivity of 39 alkanes from C_2 to C_8 is discussed and their boiling point and evaporation heat are related with the topological index M,which helps to the forecast the boiling point and evaporation heat with M.
用此拓扑指数对C2~C8的39种饱和烷烃的结构选择性进行了讨论,对其常压沸点、常沸点汽化热进行了关联,关联结果非常良好,具有很好的预测能力。
4)  vaporization-heat
汽化热
1.
Based on the thermodynamic theory of thermal pressure, the general equa tions for vaporization-heat of pure substances was derived, and then used to calculate the vaporization- heat data for thirty-two substances, including some strongly polar compounds, such as methanol, ethanol and ethylic acid etc.
本文应用热力学基本定律建立了汽化热与热压的关系,然后把立方型状态方程引入上述关系式,从而导出可推算各种物质汽化热的通用公式。
2.
Based on the thermodynamic theory of thermal pressure, the equations for vaporization-heat of pure substances were derived, and then used to calculate the vaporization-heat data for thirty-two substances including some strongly polar compounds, such as, methand, ethanol and acetic acid etc.
基于热力学热压理论,推导出了纯物质的汽化热方程,用此方程计算32种物质,其中包括某些强极性化合物的汽化热数据。
5)  latent heat of vaporization
汽化潜热
1.
Development of measurement system for saturated vapour pressure and calculating software for latent heat of vaporization;
饱和蒸汽压测量及汽化潜热推算系统的开发
2.
Measurement of latent heat of vaporization of liquid nitrogen using computer data acquisition system;
用计算机数据采集系统测量液氮的汽化潜热
3.
And according to the need of the project which author accepted, puts forward a cooling system of new type technics, that is a cooling system of using latent heat of vaporization and compares its advantages with its disadvantages, poses the application occasions of it.
论述了目前已有的各种冷却形式以及它们的机理和特点,并根据作者所承担项目的需要,提出了一种新型工艺冷却方式,即:利用汽化潜热进行吸热而冷却的方式,并对其优缺点进行了比较,提出了其应用的场合。
6)  evaporative heat sink
汽化热阱
1.
Heat transfer enhancement by evaporative heat sink formed at gas liquid interface in the process of Gas Carrying Evaporation is analysed theoretically and proved experimentally.
载气蒸发过程中的界面汽化热阱于志家,徐维勤,沈自求(大连理工大学化学工程研究所大连116012)关键词载气蒸发,汽化热阱,传热强化1前言为解决热敏性物料与易结疤型物料在蒸发浓缩时的热变质与结疤问题,大连理工大学化学工程研究所于八十年代开发出载气蒸发新。
补充资料:汽化热
      一定压强下,每单位质量物质由液相变为同温度的气相所需要的热量。汽化热又称汽化焓、蒸发热。由于汽化热只改变物质的相而不改变物质的温度,所以又称汽化潜热。
  
  物质从液相变为气相的过程叫做汽化。蒸发和沸腾都属于汽化现象。
  
  按照物质分子运动论的观点,气体中的分子平均距离比液体中的大得多。液态时,物质分子之间有较强的吸引力,物质从液相转变为气相,必须克服分子间的引力而做功,这种功称为内功。另外,当物质从液相变为气相时,体积将增大许多倍,因此还必须反抗大气压力而做功,这种功称为外功。做功需要消耗一定的能量。当液体蒸发或沸腾时,保持温度不变,都必须从外界输入能量,这就是液体汽化时需要汽化热的原因。如果液体在绝热下蒸发,则液体的温度将降低,这一现象被用来获得低温。例如,利用液氦的绝热蒸发,可获得约为0.7K的低温。
  
  汽化热因物质的种类而异,见表1。
  
  汽化热与汽化时的温度和压强有关,温度升高时汽化热减小,到临界温度时变为0。这是由于随着温度的升高,液体分子将具有较大的动能,气相与液相之间的差别逐渐减小,液体只需要从外界获得较少的能量就能汽化。而在临界温度下,物质处于临界态,气相与液相之间的差别消失了,因此汽化热为0。表2给出水在一大气压和不同温度下的汽化热的数值。
  
  气相转变为液相的过程称为凝结。气体凝结时向周围环境放热,每单位质量的气体所放出的热量叫做凝结热。在与气相相同的外界条件下凝结时,其数值等于汽化热。
  
  汽化热的量度单位是J/kg(焦耳/千克)、J/g(焦耳/克),或kJ/mol(千焦耳/摩尔)。由于历史原因,至今有些书上仍用cal/g(卡/克)作量度单位。
  

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