英文字典中文字典


英文字典中文字典51ZiDian.com



中文字典辞典   英文字典 a   b   c   d   e   f   g   h   i   j   k   l   m   n   o   p   q   r   s   t   u   v   w   x   y   z       







请输入英文单字，中文词皆可：

安装中文字典英文字典查询工具!


中文字典英文字典工具:
选择颜色:
输入中英文单字

































































英文字典中文字典相关资料:


  • What is the difference between reflectivity and reflectance?
    Reflectivity is the square of the magnitude of the ratio of the reflected electric field to the incident electric field at a surface boundary Reflectance is the ratio of the total reflected power to the total incident power For an infinitely thick material, reflectivity and reflectance are the same
  • Why is there emissivity + reflectivity + transmittance = 1?
    Reflectivity, Absorptivity, and Transmissivity are defined as being fractions of the original incident light So you could have 30% reflected, 10% absorbed, and then you would know 60% was transmitted since the remaining light had to go somewhere (conservation of energy), for a total of 100% which is equal to 1
  • optics - Calculating absorption coefficient from Transmittance and . . .
    I have some spectrum data from a sample, specifically the Transmittance and Reflectance of the sample I would like to use this to calculate the absorption coefficient
  • electromagnetic radiation - The rule breaker, emissivity + reflectivity . . .
    So if the emissivity is high for infra-red that doesn't clash with the reflectivity being high for visible light This (or rather it's converse) is exactly why greenhouses heat up in visible light They have a high emissivity and low reflectivity at visible wavelengths but a low emissivity and high reflectivity at IR wavelengths
  • Why do metals have high optical reflectivity?
    You are asking why metals have highly optical reflectivity Now this has too a little bit to do with why metals are often silver The same goes why we use aluminum in our mirrors When a photon interacts with an atom in the metal, three things can happen: elastic scattering, the photon keeps its energy level and phase and changes angle
  • optics - Reflectivity with complex refraction indices - Physics Stack . . .
    As far as I can tell, the equation above gives the reflectivity as long as the norm of the index is known, that is $$ n_1=\sqrt{n_{r_1}^2+k_1^2} \\ n_2=\sqrt{n_{r_2}^2+k_2^2} $$ in the above formula for the reflectivity, I replaced the norms of the complex numbers and not the numbers themselves,obviously
  • UV reflective surfaces - Physics Stack Exchange
    In physics, the reflectivity of a surface is described by Fresnel Equations One of the parameters of this equations is the refractive index which in general depends on the wavelength of light used So surfaces that reflect visible light need not be good reflectors in another wavelength
  • Why did high quality mirrors use aluminum coatings instead of silver?
    The reason for going with silver rather than aluminium is a slightly improved reflectivity in the near- and mid-infrared (99 1 per cent at 10 microns), but also that the emissivity of the silver coating is around 38% that of aluminium, which reduces background in infrared observations
  • Refractive Index and Reflection - Physics Stack Exchange
    Stack Exchange Network Stack Exchange network consists of 183 Q A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers





中文字典-英文字典  2005-2009