查询词典 accretion

Several feedback effects determine the final mass of a first star25: Photodissociation of H2 in the accreting gas reduces the cooling rate, but does not stop accretion.

几种反馈效应决定了一个第一代恒星最终的质量：被吸积气体中的H_2的离解降低了冷却速率，但是并不能终止吸积。

We argued that in the accretion disk around a black hole, it is significant in principle for considering the release of the internal energy of the accreting materials.

而且，当盘内物质的辐射机制是黑体辐射时，不论粘滞机制属于何种类型，结果都一样；对于自由—自由辐射，采用a粘滞律模型，与我们在文[1]中所得的结果十分类似。这表明文[1]中所取的近似足合适的。

We set up the angular momentum conservation model of wind accretion of Ba stars, and then derive the change equations of the orbital elements. Finally, combining the heavy element nucleosynthesis of AGB stars, we creatively calculate the heavy-element overabundances of barium stars in a self-consistent manner adopting accreting and mixing on successive occasions.

我们建立了Ba星形成的星风吸积的角动量守恒模型，推导出其轨道根数的变化方程，并结合AGB星的重元素核合成，通过逐次脉冲吸积与混合，自洽地计算出Ba星的重元素超丰。

In general , ba stars belong to binary system , and their heavy - element overabundances are due to the accreting material from the companions ( the former tp - agb stars and the present white dwarfs ). carrying out a series of monte - carlo simulations , the changes of orbital elements of binaries are recalculated for wind accretion scenario of the total angular momentum conservation

研究表明，钡星应该属于双星系统，其重元素超丰来自双星吸积，它的伴星已经经历了s -过程核合成，而且由在以前发生的同其伴星(以前是agb星，现已演化为白矮星)的质量传输过程中，从伴星那里获得了富含重元素的物质，这样造成了钡星的重元素超丰。

The present crustal accretion model at a fast spreading ridge predicts at least an order of magnitude difference on average in the crystallization time, the time for a crystal to cool itself to a given temperature, between the upper gabbros and lower gabbros.

通过海洋地壳生成模型得到的典型快速扩张的太平洋中脊处海洋地壳内的热结构和速度场，推算出海洋地壳内的辉长岩层上、下组的成岩时间存在大于一个数量级的差异(成岩时间是指岩浆降温到某一指定温度时所经历的时间)。

Then, we analyse in detail the mass-accretion histories and structural properties of dark haloes in high-resolution N-body simulations.

本文利用高分辨率的N体数值模拟仔细分析了暗晕的质量吸积历史和内部结构演化历史。

Dwarf novae , explosions of light from the accretion disk around a white dwarf in a binary system, are examples of this phenomenon.

在双星系统中，环绕白矮星的吸积盘产生光爆而造成的矮新星，就是此现象的例子。

After analyzing the impacting factors of natural vulnerability along the Pearl River mouth, the paper divides the coastline of approximately 412km into 25 15-minute gird cells. For assessment purposes, the six variables including geography, relative sea-level change, average tide range, regional slope, shoreline erosion or accretion rates and tropic cyclone impacting frequency are selected as assessed variables. Once each section of coastline is assigned a risk value for each specific data variable, the costal vulnerability index can be useto calculate the natural vulnerability of the areas along the Pearl River mouth. After that, the paper develops a database for assessment of coastal vulnerability to sea-level rises and protracts a 1:2,000,000 vectors CVI map of the coastlines along the Pearl River mouth.

为了探讨不同海岸带对未来海平面上升的自然脆弱性，本文以珠江口沿岸作为研究个案，在分析珠江口沿岸自然脆弱性的影响因子的基础上，把珠江口沿岸412km岸线划分为25个15′×15′的网格单元，选取了地质、海平面上升率、平均潮差、区域海岸坡度、海岸侵蚀/堆积率、热带气旋影响频率6个评价指标，应用CVI指数评价公式对珠江口地区进行海岸脆弱性评价，并建立海岸脆弱性评价数据库，绘制了珠江口沿岸1：2，000，000的数字化CVI图。

Early Mesozoic: The accretion of thickness of continental lithosphere in eastern part of North China block took place because Yangzi block subducted beneath North China block in NW direction in early Mesozoic.

中生代早期：因扬子地块向北西方向俯冲，造成了华北地块东部大陆岩石圈曾存在一次重要的加厚过程，随之而来的是俯冲板片的断离和岩石圈根的拆沉。

Besides, it can avoid the direct flow of steam and air mixture to air extraction outlet, in case of the load accretion for air ejector.

设置当汽板，防止主凝结区的蒸汽与空气冷却区的空气混合，影响传热效果；并防止蒸汽不经过主凝结区直接进入空气冷却区而增大该区域的热负荷；还可防止蒸汽-空气混合物不经过空气冷却区，直接流入抽气口，而使抽气器负荷增大

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。