成核

The synthetic reactions of sobitol acetals from sobitol and benzadehyde were considered being exothermic according to the bond energy changes of the reaction and the reaction mechanisms were described.

介绍了多元醇缩醛类成核剂的发展历程和合成工艺。从键能变化的角度分析了反应的热效应，认为在标准状态下该反应属于放热反应。

Synthetic progresses of the sorbitol acetals in process routes, the molar ratios of aldehyde to sorbitol, the reaction temperature, the types and the amount of acid catalysts, the types of acromatic aldehyde, reaction solvents and purification methods of products were reviewed at domestic and aboard with 46 references.

讨论了缩醛反应机理。从反应工艺路线、反应物醛与醇物质的量比、反应温度、酸催化剂的种类和用量、芳香醛的种类、反应溶剂及产物的纯化方法等方面全面综述了国内外山梨醇缩醛类成核剂合成研究进展。

That accounts forwhy Ga clusters occupy both the half unit cells of the 7×7 in thegrowth process.

初步的第一原理计算表明单个Ga原子吸附在7×7单胞的两半具有几乎相同的吸附能(差别仅为5meV)，这意味着Ga原子会随机地占据7×7单胞的任意一半成核生长，从而Ga团簇对7×7单胞不存在优先占据的特性。

The experiment indicates that the disks may result from the spontaneous, free organization and gathering of the iron atoms and atomic clusters driven by the internal stress.

实验证明，此类有序结构是在薄膜内应力作用下，铁原子及原子团簇在液体表面自由扩散迁移，并最终在硅油基底表面某些区域成核凝聚所致。

Bubble nucleating and porosity were improved by adding lignin granule, and cell size of the polyurethane foam was decreased. Not only physical property but also thermal property of the material were enhanced. Compared with soft polyurethane foam, tensile strength of lignin reticulated polyurethane foam was raised by 140% at most which lignin content was 5%, and the heat-degradation temperature at the first stage was 50℃ more than soft polyurethane foam which lignin content was 10%. There had been a great improvement in heat resistance of the material. It was showed that weight of biological film reached to 10000 mg/L and 12100 mg/L when the lignin content of the polyurethane foams was 5% and 8% respectively via 30-day biofilm formation testing.

实验结果表明：1，4-二氧六环对木质素的溶解能力是最好的，可使木质素均匀分散在聚氨酯泡沫塑料中；木质素颗粒的加入可改善发泡过程的成核作用，提高聚氨酯泡沫的开孔率，降低泡沫孔径，并且能提高材料的力学、热学性能，与软质聚氨酯泡沫塑料相比，木质素含量5%的聚氨酯泡沫塑料拉伸强度最大可提高140%，木质素含量10%的聚氨酯泡沫塑料发生第一阶段失重的温度提高了50多度，材料的热稳定性大大提高；经过30 天的挂膜测试，木质素含量5%和8%的聚氨酯泡沫塑料的挂模量可分别达到10000 mg/L和12100 mg/L。

The high quality nanocrystalline diamond film is successfully deposited by double bias voltage nucleation and grid bias voltage growth.

在HFCVD系统中施加栅极偏压和衬底偏压，采用双偏压成核和栅极偏压生长的方法成功制备了高质量的纳米金刚石薄膜。

A positive grid bias and a negative substrate bias voltage s are applied to the self-made hot filament chemical vapor deposited system.

在HFCVD系统中施加栅极偏压和衬底偏压，采用双偏压成核和栅极偏压生长的方法成功制备了高质量的纳米金刚石薄膜。

Therefore, small addition of halogens can promote deposition rates of diamond thin films.

这一区域的存在，将导致金刚石的淀积，而石墨的成核受到抑制。

Japan has studied the dynamic ice Making and storage system for more than 10 years, and made great amounts of research work.

对冰晶成核理论的研究和过冷水过冷度的影响因素的研究，是设计该连续制冰系统稳定工作的基础，其中过冷却器的设计尤为关键。

When citrate ions were introduced to manipulate the nucleation and growth process, star-shaped icosahedra and nanorods with pentagram cross-sections were obtained.

通过向溶液中引入柠檬酸离子调控纳米颗粒的成核与生长过程，我们首次合成出了星状钯二十面体和截面为五角星形的钯纳米棒。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。