查询词典 precursors

The spacecraft's sensitive spectrometer was able to register the chemical signatures not only of water vapor but also of hydrogen cyanide, carbon monoxide, and carbon dioxide--all precursors of the more complex molecules that scientists think eventually gave rise to life on Earth.

斯必泽太空望远镜上敏感的光谱仪不但能够记录水蒸气的化学特征，还能够记录氰化氢、一氧化碳和二氧化碳的化学特征，这些都是更为复杂分子的初级粒子，科学家们认为是这些初级粒子最终导致了地球生命的产生。

The effects of precursors, hydrothermal synthetic conditions and heat treatment on properties of products have been in...

考察前驱物、水热反应及热处理过程中的各因素对产物性能的影响，并对其合成条件进行了探讨。

High yield,well-defined gold nanocrystals with shape of icosahedron were synthesized by the rapid reduction of gold precursors with ethylene glycolin presence of polyunder hydrothermal condition for 1 h.Au icosahedron is one of multiple twinned particleswhich has 20 faces,each were enclosed by {111} facet.

采用水热法在乙二醇体系中成功的制备出了形状规则、尺寸为200-300nm的二十面体金纳米粒子，研究结果表明，所合成的纳米颗粒是面心立方晶型，每个晶面都是{111}面。

No indene was found, clearly showing that indanes and indenes may originate from different precursors, and algae lived in saltwater are important contributors to the indanes.

没检测到茚类化合物，说明二氢化茚和茚可以源自不同的先质，生活于咸水环境的低等生物是二氢化茚类化合物的母质之一。

The pink intranuclear inclusions in the erythroid precursors seen here are characteristic for parvovirus infection.

红细胞前体内的粉红色核内包涵体是微小病毒感染的典型特征。

Enaminones are also valuable precursors for α-iodol enaminones, 3-amino sugar derivatives, azo-compounds,β-aminoketone, as well as tetrahydropentalenes, tetrahydroindenes, and hexahydroazulenes.

烯胺酮类化合物同时也是α-碘代烯胺酮类化合物、3-氨基糖衍生物类化合物、氮杂化合物、β-氨基衍生物类化合物和四氢并环戊二烯类化合物和四氢茚类化合物的重要前体。

Hydroxyl ketene dithioacetals were treated under diversely catalyzed conditions, and a wide range of significant compounds and synthetic precursors thus were obtained.

羟基二硫缩烯酮类化合物可以通过各种不同的反应条件进行多种转化，能够获得许多有意义的化合物和合成潜体。

It was demonstrated that the reason of spiramycin production increased creased by vitamins was the promotion of synthesis of precursors and the formation of lactone.

由此表明维生素的添加促进螺旋霉素发酵合成可能是因为维生素促进了过程中前体物质的合成，从而增进了内酯环的形成。

Based on the detailed analysis of a variety of factors affecting stability of taxol production in Taxus cells, it was discovered that initial cell density and the relevant concentrations of substrates, elicitors and precursors significantly affected stability of taxol production; farther study showed that addition of elicitors at appropriate cellular state was the key to steadily improve taxol yield, especially, the proper cellular state was at the end of lag phase and at the beginning of the stationary phase, which was also proved by the cellular ultrastructure.

对影响红豆杉细胞紫杉醇产量稳定性的各类因素进行详细分析，发现细胞的接种密度以及与之相适应的培养基的基质浓度、诱导子浓度和前体浓度是影响紫杉醇产量稳定的重要因素；进一步研究发现，选择细胞处于合适的状态时加入诱导子是稳定提高紫杉醇产量的关键，细胞合适状态特别是延迟期末和稳定期初最合适，细胞状态的超微结构观察结果也证明了这一点；同时研究发现采用合适的同步化处理获得的细胞初始周期时相加入诱导子与紫杉醇产量稳定密切相关，且以低温同步化处理得到的细胞周期的分裂中期相的细胞加入诱导子不仅大大提高了紫杉醇的产量，而且诱导子加入时间大大缩短，有利于大大提高紫杉醇生产率。

The results showed that there were two kinds of grains in the cells,one was large and had low electron density,Gl for short,while the other was small and had high electron density,Gh for short.The latter ones had a circle around it which can be seen through the microscope.During the aroma releasing period,the shape of the two grains changed distinctly,which led to the inference that Gl was the leucoplast,the store-room of aroma precursors or energe substances,and that the Gh was probably the lysosome which is related to the enzyme system?s aroma producing.The circle around Gh is the formed fragrant constituents and the aroma forming is the result of the interaction of Gh and Gl .

结果发现，茉莉花瓣细胞中存在电子密度较低、体积较大的颗粒和电子密度较高、体积较小的颗粒（分别简称为Gl和Gh颗粒），并在Gh颗粒周围存在清晰的晕圈；在茉莉花释香过程中，两种颗粒在形态上均发生明显的变化，推测Gl颗粒可能是白色体，是茉莉花香气前体物或能量物质的贮存器，Gh颗粒可能为溶酶体，与香气形成的酶系统有关，Gh颗粒周围存在的晕圈可能是香气物质，香气物质的形成是Gl和Gh颗粒相互作用的结果。

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性，但我大喊，并在他们的方向扔石头让他们过的线索，远离我，以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。