查询词典 rings

A range of oligoaryls having alternating para- or meta-benzene-furan rings is synthesized by rapid convergent/divergent method from the annlation of a propargylic dithioacetal and an aldehyde having a propargylic dithioacetal moiety as the substituent.

中文摘要结合分流法/汇集法，利用炔丙基硫缩酮单体和另一具有醛基的单体进行环化反应，可以迅速合成对位及间位取代苯环呋喃交错寡聚物。

In order to search for the new pyrazolyl-heterocycles lead compounds, eight pyrazolyl- were synthesized from 3-ethyl-1-methyl- 4-substituted-5-pyrazolecarboxylic acid chloride and nitrogen heterocyclic rings such as 3-methyl-5-pyrazolone, 1H-3-ethyl-5-pyrazole ester, etc.

为了寻求新的含吡唑双杂环先导化合物，用 4 取代 1 甲基 3 乙基 5 吡唑甲酰氯与 3 甲基 5 吡唑酮、3 乙基 5 吡唑甲酸乙酯等含氮杂环反应得到了 8个新的含吡唑环的双杂环类化合物。

The nitrogen in the coal exists in the forms of pyridine (N-6), pyrrolic and pyridone (N-5), quaternary nitrogen and nitrogen oxides. The N-Q near 401.5eV is assigned to a protonated or oxide form of pyridinic nitrogen. On this basis, the nitrogen in six-membered rings is the dominant in Yibin coal.

研究结果表明，宜宾煤中氮的官能团有4种，即吡啶(N-6)、吡啶(N-5)、质子化吡啶和氮氧化物，其中吡咯含量最大，煤中的N-X就是N-O，是煤中吡啶结构氮与氧直接结合的结果。

There are extensive works on chalcones and azachalcones has been reported. However, there are very few reports on azachalcones, especially the azachalcones with two pyridyl rings.

关于查尔酮的报道已经很多，但有关氮杂查尔酮特别是带有两个吡啶环的氮杂查尔酮的报道却为数不多。

Two ending pyrylium rings showed a quinonoid structure.

甲川链取代基对分子的晶体结构和宏观性质有很大的影响。

You can often find teddy bear rattles or teething rings that have teddy bears on them.

你可以经常发现泰迪熊摇铃或暂时性的戒指有泰迪熊玩具，对他们的影响。

"In such a case, the only way to get the engine Back into good operation condition is to refinish the cylinders and fit new piston s and new rings to them."

在这样的情况下，要使发动机保持良好的工作状态，只有整修气缸表面，并配装新的活塞和活塞环。

"In such a case, the only way to get the engine Back into good operation condition is to refinish the cylinders and fit new pistons and new rings to them."

在这样的情况下，要使发动机保持良好的工作状态，只有整修气缸表面，并配装新的活塞和活塞环。

What are the three most popular types of retaining rings?

最流行的护环是那三种类型的？

The dental alloy component, the wax patterns invested with rings or ringless can affect the

缩不同，铸圈的使用与否影响基底合金的铸造收缩。

The labia have now been sutured together almost completely.The drains and the Foley catheter come out at the top.

此刻阴唇已经几乎完全的缝在一起了，排除多余淤血体液的管子和Foley导管从顶端冒出来。

To get the business done, I suggest we split the difference in price.

为了做成这笔生意，我建议我们在价格上大家各让一半。