Then second class are the macroscopic models describing directly macroscopic quantities such as charge density , charge current density , energy density and temperature etc . 另一类是宏观模型，其直接描述电荷密度，电流密度，能量密度和温度等一些宏观量。
After obtaining optimized laser frequency 5hz accepted - pulse - times 10 / second by experiments , laser power density increased little by little is focused on study 实验在优化频率为5hz ，受光次数10次秒时，重点研究了激光能量密度由小到大对晶化性能的影响。
The researchers think they have devised a biofuel that has a 40 % higher energy density than ethanol , that repels water and that can be made relatively speedily 研究人员们认为设计出了一种比乙醇的能量密度高出40的生物燃料，而且它排斥水并能在制造速度上相对快捷。
But when theorists try to compute the energy density associated with the quantum vacuum , they come up with values that are at least 55 orders of magnitude too large 然而，当理论学家尝试计算这个量子真空的能量密度时，他们得到的结果比目前的观测值至少大55个数量级。
The lithium ion batteries ( lib ) are regarded as the best one , because they have high working voltage , long cyclic life , high energy density and no environmental pollution 锂离子电池以其工作电压高、循环寿命长、能量密度高、无环境污染等优势而成为人们的首选。
If the dark energy density decreases as the universe expands , then the switch - over point occurs earlier in time than it would for a model assuming constant dark energy density 暗能量密度会随宇宙膨胀而递减的模型，相较于暗能量密度是常数的模型，其转变的时间点将较早发生。
When designed , the high - speed generator with a permanent magnet ( pm ) rotor is preferred because of its simple structure , without excitation high energy density of the pm material 永磁转子式高速发电机由于具有结构简单、不需励磁、效率高和能量密度大等优点成为高速发电机设计时的首选。
Therefore , data from a wide variety of independent cosmological and astrophysical observations strongly suggest that most of the energy density of the universe today may be contained in empty space 换言之，不同的研究和观测数据皆表明，现时宇宙中大部份的能量密度很可能隐藏于虚空之中！
I find that the crystallization performance is the best at laser power density 300mj / cm2 . it means crystallization degree is the best , grains are the most uniformity and film stress is the least 实验发现在能量密度为300mj cm ~ 2时晶化性能较好，即晶化度最高，晶粒最大且均匀，薄膜应力最小。
The latest supernova results are consistent with theories positing a constant dark energy density , but they also agree with most of the models that assume a varying dark energy density 虽然最新的超新星观测结果，与暗能量密度为常数的理论不相抵触，但它也符合大多数假设暗能量密度为变数的理论。
