查询词典 yields

Maximum yield research can help point the way to improved yields through better management of all yield components.

最高产量研究有助于通过更好地协调所有产量构成因素来指明提高产量的途经。

An primary optimization for medium composition in shake flask showed the best carbon source, nitrogen source , culture volume , incubating quantity and pH after having completed studying the relation between thalli form,zymotic condition and metabolized yields .

通过摇瓶培养，研究发酵条件对菌体形态、产物产量的影响，初步优化了发酵培养基组成，确定了最佳碳源、氮源、装液量、接种量、pH等。

A series of methyl 2,7,7-trimethyl-5-oxo-4-aryl1,4,5,6,7,8- hexahydroquinoline -3-carboxylate were synthesized by the reaction of aromatic aldehydes,dimedone and methyl acetoacetate using ammonium acetate as catalyst in glycol under microwave irradiation with 82%～98% yields in 4～6 min.

微波辐射下以芳醛、达咪酮、乙酰乙酸甲酯为原料，乙二醇为溶剂，醋酸铵为催化剂合成了一系列2，7，7-三甲基-5-氧代-4-芳基-1，4，5，6，7，8-六氢喹啉-3-羧酸甲酯化合物，反应时间4~6 min，产率82%~98%。

The experimental results showed that the partition coefficients and yields of 2,3-butanediol and acetoin reached 11.9,9.10,83.48%, 79.37%,respectively,when the concentration multiple was 70%,the concentration of K_2HPO_4 added was 45%,and the concentration of 2,3-butanediol in top phase reached

结果表明：当发酵液浓缩70%后，加入45%的磷酸氢二钾，乙偶姻、2，3-丁二醇的分配系数最高，分别为11.9、9.10；回收率较高，分别为83.48%、79.37%；上相中2，3-丁二醇浓度最高可达420g/L。

Gas chromatography was employed to quantify the output of metabolization,and it was found that the yield of diacetyl for the mutant UV-3 was 18.7 fold to the wild-type 10293,up to 1.045g·L~(-1).Acetoin and ethanol yields were decreased by 48.4%and 71.4%,respectively.The yield of acetate was increased by 34.6%.

利用气相色谱测定代谢产物量，分析诱变前后菌株代谢途径中碳源的流向，结果表明突变株UV-3的丁二酮产量提高18.7倍，达到1.045g/L，乙偶姻产量降低48.4%，乙醇产量降低71.4%，乙酸产量提高34.6%，且遗传性质稳定。

Yields from chiral bisoxazolines (5a) with diethyl oxalate using NaOCH〓 as base for the first time. The structures of chiral multioxazolines and their intermediates, multi (β-hydroxylamide) s, were characterized by 〓H NMR, IR, mass spectra and elemental analysis. The catalytic activities and enantioselectivities of chiral multi (β-hydroxylamide) s (4) and chiral multioxazolines (5～8) were investigated by using acetophenone and β-acetonaphthone as former chiral ketone, KBH〓 or NaBH〓 as reductive reagent in chapter three.

在此基础上，对合成方法作了创新，以羧酸或酯为原料，在无催化剂的条件下与手性α-氨基醇反应，通过回流分水或脱醇的方法，一步反应合成了手性多噁唑啉（5～8），产率为89.2%～98.4%；以手性双噁唑啉（5a）为原料，在NaOCH〓的作用下，与草酸二乙酯反应，首次合成了呋喃类双嗯唑啉（6a），产率为72.9%～75.6%。

N-substituted pyrroles are synthesized by reacting acetonylacetone with carbamic ester , catalysted by p-toluenyl sulfonic acid, heated at reflux temperature for 6h, collecting evolved water, giving to 75% yields, which is 26% more than the literature value.

以对甲苯磺酸为催化剂，用甲苯作溶剂，使2，5-己二酮与氨基甲酸酯在110℃反应6h，合成了5种氮取代吡咯衍生物，其中两种未见文献报道，反应产率均达到75％以上，比文献值高出了26％。

Organozinc reagents can react with a variety of α,β-acetylenic ketones and aldehydes in the absence of any catalyst. The one-pot reaction affords β-branched Baylis-Hillman type adducts, the multifunctionalized alkenes, in excellent yields with high stereoselectivity.

这种顺式亲核加成反应的发生是由于该类有机锌试剂既具有较强的亲核性，又具有Lewis酸的特性，使有机锌中R基团从同位进攻中心碳原子而形成新的碳碳键。

Family Acipenseridae: Beluga, the largest and most rare, yields large translucent golden-grey eggs.

鲟科中的欧洲鳇体形巨大，产量很少，其生产的鱼籽透明，个儿大，具有金灰的色泽，乃鱼子酱至尊。

Half the amount of cylinder power is added algebraically to the sphere power , and this yields the resulting spherical equivalent power.

即用球面镜光度与一半柱镜光度的代数和，计算结果就是等效球面的光度。

It's bell can reach over a meter in diameter.

它的身体最大可以达到直径1米多。

Now they are overdue and I shall have to pay a fine.

现在他们过期了，我不得不付罚款。