乙酸的

The results of in vitro culture show that sodium fumarate increased NDF digestibility, total volatile fatty acid concentration and propionate proportion, decreased ammonia concentration, and acetate, butyrate, and valerate proportions, and acetate to propionate ratio when using bermudagrass hay as the substrate.

体外培养的结果显示，当使用百慕达乾草为受质时，添加延胡索酸钠，提高了中洗纤维消失率、总挥发性脂肪酸浓度和丙酸的百分比，降低了氨浓度、乙酸、丁酸和戊酸的百分比，乙酸对丙酸的比例降低。

The results show that there were no significant differences among the four forage rations in rumen pH, the concentrations of total volatile fatty acids, acetate, propionate, the ratios of acetate to propionate, butyrate, isobutyrate and valerate（P﹥0.05）. Only in 11:30, the concentrations of isovalerate caused by ration A and B were significantly higher than the other two rations(P﹤0.05).The milk yield caused by the ration C was significantly lower than the others (P﹤0.05). However, there were also no significantly differences among these four rations in the DM, fat, sugar, protein and scc of the milk. The milk fat and sugar of ration B and C were higher than ration A and D in number as well.

试验结果显示：各粗料组合日粮对各个时间点的瘤胃发酵指标：pH、TVFA、乙酸、丙酸、乙酸/丙酸、丁酸、异丁酸、戊酸浓度均无显著差异（P﹥0.05），只在11：30时，日粮A、B的异戊酸浓度显著低于日粮C、D (P﹤0.05)；日粮C的产奶量显著低于其它三个日粮，而在乳干物质、乳脂、乳糖、乳蛋白、体细胞数上，各日粮均无显著差异，从数值上看，日粮B、C的乳脂和乳糖高于A、D。

Given the current complexity of industrial recovery of 3'-methyl-2'-butenyl 3, 3-dimethyl-pentenoate and the decomposition problems with 2-methyl-1-butene, research was conducted on a process for direct recycling of MBDP involving an ester exchange reaction of MBDP with either methanol, trimethyl orthoacetate, or solutions of methanol and trimethyl orthoacetate.

针对目前工业上回收3，3-二甲基－4-戊烯酸－3'-甲基－2'-丁烯酯工艺复杂、异戊烯大量分解问题，研究了MBDP直接返回循环使用工艺，MBDP与甲醇、原乙酸三甲酯或与甲醇原乙酸三甲酯混合溶液进行酯交换反应的回收新工艺，比较了四异丙基钛酸酯、甲醇钠、氢氧化钾用作酯交换催化剂的效果，筛选出回收MBDP&一锅煮&最佳工艺：按照n：n：n：n＝1.0：9.8：9.2：0.05物质的量比投料，74℃~78℃反应21h，MBDP转化为贲亭酸甲酯和异戊烯醇，单程转化率87.7%，用85%的磷酸中和甲醇钠，蒸出甲醇，直接用于合成贲亭酸甲酯。

In order to isolate the active compounds in ethyl acetate fraction of Psoralea corylifolia L., activity-guided isolation was performed along with chromatographic techniques. Four active compounds were isolated from ethyl acetate fraction and identified by their NMR spectral data and physical-chemical properties. They are corylin and bavachin, which showed stimulating effect on osteoblastic proliferation and differentiation, isopsoralen and psoralen exhibited activity of promoting cell differentiation in some degree.

为了追踪分离补骨脂乙酸乙酯萃取物中的活性成分，本实验采用多种色谱分离技术，以活性测试为导向，结合波谱技术及理化数据，从补骨脂乙酸乙酯萃取物中分离并鉴定了4个活性化合物的化学结构，它们是具有促进细胞增殖和分化作用的补骨脂异黄酮和补骨脂二氢黄酮，对细胞分化有一定促进作用的异补骨脂素和补骨脂素。

Those biodegradable materials finally form into CO2 and H2O via culture of tricarboxylic acid cycle, which can be excreted from lung, kidney, and skin. Hydroxyacetic acid is a metabolic product of amino acids. Therefore, velocity of bioldegradable materials can be controlled in vivo. The recent contraception focuses on discover a sustained release system of biodegradable materials.

生物可降解材料包括聚乳酸、聚ε-己内酯、乳酸-羟基乙酸共聚物等，这些材料有很好的生物相容性，植入体内后可经生物降解成乳酸单体，经三羧酸循环后最终成为CO2和H2O，经肺、肾、皮肤排泄，羟基乙酸也是机体氨基酸代谢产物，而且生物可将解材料在体内降解速度是可控的，用生物降解聚合物作为药物载体的缓释避孕系统是目前材料学以及避孕节育研究的一大重点。

The peracetic acid can be used in the disinfection of thermolabile packaging material in the production process.

结论经过氧乙酸灭菌的塑料瓶能达到无菌要求，酸的残留量对ph值的影响不显著，生产上可用过氧乙酸灭菌法对不耐热的内包材进行灭菌。

A series of novel polyethylene glycol derivates was synthesized by esterification of chloroacetic acid with polyethylene glycol. Because of the good reactive activity of α-chlorin in the esters it can react with 5-fluorouracil, thus the conjugate can be obtained .

采用氯乙酸与不同分子量的聚乙二醇进行酯化反应得到氯乙酸聚乙二醇酯，由于酯中的α-氯具有良好的反应活性，将它再与抗癌药物5-氟尿嘧啶结合制备了不同分子量的高分子前药。

Continuous use of a disinfectant solution for long periods eventually results in dilution or decreased activ- ity.89 Commercial test kits are available for chlorine, hydrogen peroxide, glutaraldehyde, and peracetic acid to determine whether an effective concentration of active ingredients is present

消毒溶液的长时间持续使用最终导致溶液的稀释或活性降低。商业测试包可以用于测试氯制剂、过氧乙酸、戊二醛和过氧乙酸在重复使用和稀释后活性成分的有效浓度。但是此类测试包的可靠性尚未确定。

In order to improve the thermal stability of yellow iron oxide pigments, a new balance precipitant coating silicon method with ethyl acetate as potential acid by controlling the dehydrolysis velocity of ethyl acetate was used.

为了改善铁黄颜料的耐热性，运用乙酸乙酯作为潜伏性酸试剂，研究了一种新的铁黄表面均匀包覆二氧化硅的方法，即通过控制乙酸乙酯的水解速率来实现在铁黄表面均匀包覆二氧化硅。

The effects of both molar ratio between reactants and reaction temperature on the products were investigated.

考察了乙酸铅和硫脲的摩尔比以及反应温度对合成产物的影响，发现当乙酸铅和硫脲的摩尔比为1：1时，得到大量的PbS纳米棒束，并初步探讨了其形成机理。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。