最佳值

The results show that the yield of compound 5 reached a maximum of 65% under the optimum reaction conditions, where the pH of the reaction medium was 3.8~4.0, the reaction temperature was 85~90 ℃, and the molar ratio of zinc powder to compound 1 was 2.6:1. The optimum oxidant for the selective oxidation of α-methyl on compound 5 was sulfuryl chloride, and the yield of the product was 52.5%.

结果表明，合成化合物5的最佳反应条件为：反应介质pH值为3.8~4.0，反应温度85~90℃，锌粉与反应物1之间的摩尔比2.6：1，产物收率达到65%；化合物5中α-甲基选择性氧化反应的最佳氧化剂为硫酰氯，产物收率达到52.5%。

Each of cores were carried on NMR measurement after each of six or seven different centrifugal force, author can got that 200 psi was suitable to be best centrifugal force calibrating T_2 cutoff value for glutenite cores, and 400 psi was suitable for carbonatite and vulcanite cores in this ***, and corresponding lower limit of valid throat is 0.1μm for glutenite and 0.05μm for carbonatite and vulcanite.

对本文实验选取的岩心而言，低孔、低渗砂砾岩岩心T_2截止值标定时适合的最佳离心力均大致可取200psi，而碳酸岩和火山岩岩心最佳离心力均大致可取400psi，对应的有效渗流喉道半径下限砂砾岩为0.1μm，碳酸岩和火山岩为0.05μm。

Aspergillus WQ is selected to explore the factors which affect producing enzymes. The best carbon source is crystallitic cellulose+straw powder, the best nitrogen source is peptone+yeast abstract cream, the best growing temperature is 35℃and the best initial pH is 5.5. WQ can produce the largest quantity of enzymes after being cultivated eight days.

从50℃左右牛粪自然堆肥中筛选了一株产酶量较高的曲霉WQ，对影响其产纤维素酶的因素和酶的热稳定性进行了初步研究，结果表明：液体发酵时，该菌最佳碳源是微晶纤维素+稻草粉组成的复合碳源，最佳氮源是蛋白胨+酵母膏的复合氮源，最适生长温度为35℃，最适起始pH值为5.5，在生长第8天产酶量最高。

Firstly, polyacrylamide with 26 million molecular weight was compounded in lab through establishing optimum compounding initiator proportionality of 1:1. 3 and mass concentration of 170 mgL^(-1), temperature of 10 ℃, acrylamide mass percentage of 25%, electrical conductivity of 3.6 μSm^(-1) and pH value of 6.57. The salt-resistance, thermal endurance and shear-resistance of polyacrylamide could be enhanced b introducing sulfonic acid group or styrene sulfonate group or drawing the two groups above at the same time. Secondly, chelator HEDP, bactericide isoquinoline ketone and oxygen scavenger thiourea were optimized to improve the compatibility of polyacrylamide and formation water.

在由室内试验确定了复合引发剂最佳比值1：1.3和质量浓度170 mgL^(-1)、合成最佳温度10℃、丙烯酰胺单体质量分数25%、电导率3.6μSm^(-1)和pH值6.57后，合成出相对分子质量高于2.6×10^7的聚丙烯酰胺，同时通过丙烯酰胺单体复配引入磺酸基团、苯乙烯磺酸基团或同时引入此两种基团，提高了聚合物的抗盐、抗温、抗剪切性能；后针对聚丙烯酰胺与地层水配伍性差的问题，优选出HEDP螯合剂、异噻唑烷酮杀菌剂和除氧剂硫脲，对聚合物稳定效果明显。

The results show that the optimal parameters of esterification are as follows: 4% of SO42-/ZrO2, molar ratio of methanol to litsea cubeba kernel oil 101, 68 ℃ of reaction temperature and 4 h of reaction time, the acid value decreases to 2.52 mg/g. Compared with the traditional acidic-catalyzed method, this method has the advantages of no acid proof equipment, easy to recycle catalyst and no acidic waste water emission. The optimal parameters of transesterification are as follows: 25 ℃ of reaction temperature, 0.5% of hexadecyl-trimethyl-ammonium bromide, 1% of NaOH, molar ratio of methanol to the oil 61 and 15 min of reaction time. The ester exchanging rate is 97.6%. This method adopts phase transfer catalyst and produces industry prospect, which has many advantages such as energy-saving and time-saving under room temperature.

研究结果表明，固体酸SO42-/ZrO2催化酯化反应的最佳条件为：油重4%的SO42-/ZrO2，醇油摩尔比为101，温度为68 ℃，反应时间为4 h，原油酸值降到2.52 mg/g；该法相对浓硫酸催化酯化法具有不需耐酸设备、催化剂易回收、无废水排放等优点；相转移催化酯交换反应的最佳条件为：温度为 25 ℃，0.5%的十六烷基三甲基溴化铵，油重1%的NaOH，醇油摩尔比为61，反应15 min，原油酯交换率达到97.6%；采用相转移催化技术，反应在常温下进行，大大减少了能耗，缩短了反应时间，具有的产业化前景。

Results The optimum conditions for the extraction of Peucedanum praeruptorum Dunn was as follow: 80 % alcohol was used as solvent, and 8 times the amount of alcohol was added, the mixture was kept refluxing for 1.0 h for the first time; then 6 times the amount of alcohol was added and the mixture was kept refluxing for 0.5 h for the second time; Four times the amount of alcohol for 0.5 h for the last time.

结果 白花前胡的最佳提取工艺为用质量分数80 %的乙醇提取3次，提取时间分别为1.0、0.5、0.5 h，3次所用溶媒量分别为药材质量的8、6、4倍；按照筛选出的最佳工艺条件进行的3次重复性实验，测得浸膏中8-甲氧基补骨脂素含量质量分数为0.094 %，折合1 g生药中含量为0.171 2 mg，与预测值基本一致。

With routine method, from having elected contents higher one RNA bacterial strain among several saccharomycetes, beer yeast, and the method with Shan factor experiment have studied an experiment being bacterial strain's turn to produce more proper RNA culture medium made up of , optimum the pH value fermenting and the best fermentation time.

本实验用常规方法从数株酵母菌中选出了一株RNA含量较高的菌株——啤酒酵母，并用单因素实验的方法研究了该菌株产RNA较适宜的培养基组成、最佳发酵pH值和最佳发酵时间。

Organic surface modification of silver-loaded TiO2 with stearyl amine is investigated. Effects of reaction conditions such as modification time, modification temperature, pH value and content of stearyl amine on the surface modification of silver-loaded TiO2 are systematically determined.

采用十八烷胺为改性剂对载银二氧化钛进行改性，考察了十八烷胺添加量、改性时间、改性温度及pH值对表面改性的影响，从而确定了最佳用量和最佳改性条件。

This changes the costs and profit of the common oreand vanadic and titanic ore. The rate of the common ore and vanadic and titanic orechanges with the profit's change.

因此，找到普通矿冶炼和钒钛矿冶炼二者最佳的比例值，根据生产成本及市场价格的变化，及时调整普通矿冶炼和钒钛矿冶炼的比例，以获取最佳的经济效益是非常有意义的工作。

Theresults indicated that the initial desorption rate of As was higher than As, but thefinal desorption percentage of As was two times higher than As; that in therange of pH(6.5-8.5), the desorption of As was the lowest（pH=6.5）,and thepercentage increased with the pH value increasing or deescalating, but for the As,thepercentage increased with the increase of pH; that the supersonic accelerated desoptionof arsenic and the final percentage was lower than non-supersonic; that on the conditionof UV-light ,in a word, it took negative effect to desorption The"reproduced process"has been used in the procedure of regeneration.

实验结果表明，初始阶段，三价砷的脱附率高于五价砷，但最终脱附率三价砷低于五价砷；三价砷、五价砷在不同温度下的脱附实验表明三价砷的最佳脱附温度低于五价砷的最佳脱附温度；在pH=5.5-8.5时，随着pH的增大，五价砷的脱附率具有先减小再增大的趋势，在pH为6.5时脱附率降至最小；在pH=5.5-8.5时，三价砷的脱附率随pH的增大而增大；不论是三价砷还是五价砷的脱附过程，超声波条件都会促进脱附速率(来源：ecABC论a4文网www.abclunwen.com)的增加，并且最终的脱附率要高于无超声波条件下的脱附率；紫外光照条件下，随着光照时间的增加，两种价态砷的脱附率会达到一个较高的值，再降低。总体而言，紫外光照的存在不利于脱附的进行。

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％。