stellar photometry星体光度学This formation, called an accretion disk, may be very important in some stellar birth sequences.这种构成物即所谓吸积盘, 它在恒星诞生的某些阶段可能是非常重要的.If the stellar spectrum is known, the albedo of the dust can be obta...
Many forest tree species have multiple archegonia which, after fertilization produce a number of proembryos.许多林木树种都有颈卵器, 受精以后便产生许多原胚.A similar section through the female plant reveals several bottle - shape archegonia , ...