氢氧化钠

The method is simpler, rapider and more sensitive than those of the conventional spectrophotometry.

在这个方法中，硫胺素作为荧光试剂和钴离子于0.65%氢氧化钠介质中反应，形成一种具有强荧光性的物质—硫胺荧。

Samples were saponified with 20 g/L sodium hydroxide. The sexual hormones were then extracted with dichloromethane-acetic acetate (40∶1, v/v) under acidic conditions (pH 3, adjusted with 1 mol/L HCl ). An XTerraTMRP18 column was employed and a mixture of water-methanol-acetonitrile (50∶32∶18, v/v) was used as mobile phase. The seven sexual hormones were detected at 230 nm. The average spiked recoveries for the seven sexual hormones ranged from 75.6% to 97.8% with relative standard deviations of 1.9% to 7.2%. The linear ranges of determination were from 5 to 50 mg/L with correlation coefficients of 0.9999, and the limits of detection were from 3.7 to 12 ng.

先在试样中加入20 g/L氢氧化钠溶液与油脂进行皂化反应，然后用二氯甲烷-乙酸乙酯(体积比为40∶1)混合液在酸性条件下(pH 3)萃取，选择XTerraTMRP18色谱柱，以水-甲醇-乙腈(体积比为50∶32∶18)混合液为流动相，在波长230 nm处检测。7种性激素分离良好并排除了样品中杂质峰的干扰，低、高浓度平均回收率范围为75.6%~97.8%；相对标准偏差为1.9%~7.2%；检出限为3.7~12 ng。

Compared with the time, the impact of temperature factors on the layer thickness is greater. The surface hardness of 45 steel is greatly improved for the exist of FeB; the corrosion resistance of boronizing layer is excellent which can resist hydrochloric acid, sulfuric acid and sodium hydroxide.

相比而言，温度对渗硼层厚度的影响大于时间的影响；渗硼层中FeB相使表面硬度显著提高；渗硼层抗盐酸、硫酸、氢氧化钠腐蚀性优良。

Nano-cobalt blue precursor was prepared by mixing two types of microemulsion solutions of oleic acid/butanol/sodium carbonate solution and oleic acid/butanol/sodium hydroxide solution for reaction, into which Co~(2+) and Al~(3+) were solubilized respectively.

将Co2+和Al3+分别溶于油酸/正丁醇/碳酸钠水溶液和油酸/正丁醇/氢氧化钠水溶液制成微乳液，再将2种微乳液混合，反应生成纳米钴蓝前驱体。

Trimethylolheptane was synthesized through consecutive aldol condensation and Cannizzaro reaction of octylaldehyde and formaldehyde, using sodium hydroxide as catalyst.

为制备新型芳香缓释聚氨酯微胶囊合成了两亲性单体三羟甲基庚烷。以氢氧化钠为催化剂，辛醛和甲醛在较低温度下发生羟醛缩合反应生成2，2-二羟甲基辛醛。

Viscose manufacturing process involves the reaction of cellulose with sodium hydroxide to form an alkali cellulose.

粘胶的生产过程包括纤维素与氢氧化钠反应形成碱纤维素的过程。

In this paper, aging time of alkali cellulose was confirmed by researching the effect of aging time of alkali cellulose to its ability of withstanding alkali; The effect of temperature, the mass ratio of intermediate to cellulose, time, NaOH concentration on the mass and capacity of product.

研究了碱纤维的老化时间对抗碱能力的影响，确定了碱纤维的老化时间；研究了氢氧化钠的用量、中间体与纤维素的质量比、反应温度和反应时间对产物质量和产物交换容量的影响，并用红外光谱对产物的结构进行了表征。

Treatment of purified wood pulp with 18% sodium hydroxide solution produces alkali cellulose.

用18%氢氧化钠溶液处理纯化木浆生产出碱性纤维素。

The result showed that aging time of alkali cellulose should he 60℃, the preparation condition optimized of 3-ureido-2-hydroxypropyl cellulose should be the temperature of reaction at 60℃, reaction time 3.5-4h, the mass ratio of intermediate to cellulose should be 5, NaOH concentration should be 1 mol/L.

结果表明：棉纤维的老化时间为10 h，3-脲基－2-羟基丙基纤维素的制备工艺条件以温度60℃，m（3-氯－2-羟丙基脲）／m＝5，反应时间3.5~4 h，氢氧化钠的浓度以1 mol/L为宜。

The factors which mostly affect the quality and output of the product including molar proportion of reagents, reaction temperature, alkaline concentration and reaction time are analyzed. After orthogonal experiment, it is concluded that the optimized reaction condition is that acetone and furfural are charged with equal molar quantities at 40 with sodium hydroxide (0.10 mol/L) and the operation time 5 h.

通过对影响亚糠基丙酮质量和收率的主要因素原料配比、反应温度、碱浓度、反应时间等单因素实验，探索出合成亚糠基丙酮的优化反应条件为：原料配比n：n=1.0：1.0、反应温度40℃、氢氧化钠溶液浓度为0.01 mol/L、反应时间5h。

I can not make it blossom and suits me

我不能让树为我开花

When temperatures are above approximately 80 °C discolouration of the raceways or rolling elements is a frequent feature.

当温度高于 80 °C 左右时，滚道或滚动元件褪色是很常见的特征。