亚硝酸

The optimal synthesis conditions are that when the mass ratio of amylum and acrylamide is 3:1; NaOH is 75% of acrylamide; the concentration of ammonium ceric nitrate is 5 mmol/L; the N, N′-methylenebisacrylamide and acrylamide is 0.2%; and the reaction temperature controlled in (60±2)℃, the water absorptivity of produced super absorbent can reach to 750 g/g for tap water.

最佳合成条件是：在淀粉与丙烯酰胺的质量比为3：1、氢氧化钠为丙烯酰胺质量的75%、硝酸铈铵的浓度为5mmol/L、交联剂N，N'-亚甲基双丙烯酰胺与丙烯酰胺的质量比为0.2%、反应温度控制在(60±2)℃的条件下，制得的保水扩蓄剂吸水率可以达到750 g水／g。

Methods: In the presence of hydrochloric acid or nitric acid, geranyl sulfone was prepared from geraniol in isopropyl alcohol or THF under reflux conditions for 18 h or 28 h, respectively.

以异丙醇或THF为溶剂，盐酸或硝酸为催化剂，香叶醇与苯亚磺酸钠回流反应18或28 h得香叶基砜。

CeO2 nanoparticles were prepared using cerium nitrate and hexamethylenetetramine as starting materials, and the prepared powders were collocated into polishing slurry for chemical mechanical polishing of GaAs wafer.

以硝酸铈和六亚甲基四胺为原料制备出不同粒径的纳米CeO2粉体颗粒，将纳米CeO2粉体配制成抛光液并用于砷化镓晶片的化学机械抛光。

By using water bath method that an aqueous solution of zinc nitrate（Zn（NO3）2·6H2O）reacted with an aqueous solution of equimolar methenamine（C6H12N4）,ZnO nanomaterials with controllable morphologies are successfully prepared. The influences of solution concentration and substrates on morphology of ZnO nanomaterials are discussed.

用硝酸锌（Zn（NO3）2·6H2O）与六亚甲基四胺（C6H12N4）以等浓度配制成反应溶液，通过水浴法制备出了形貌可控的棒状ZnO纳米结构，讨论了不同反应浓度及衬底对ZnO表面形貌的影响。

objectiveto analyze the total content of flavonoids in nigella glandulifera preyn et sint by colorimetric method.methodsrutin was used as reference substance and the detection wavelength was 500 nm.

目的采用比色法测定维吾尔药黑种草子中总黄酮的含量。方法以芦丁作对照品，以亚硝酸钠-硝酸铝-氢氧化钠体系为显色剂，检测波长为500 nm。

Nitro-4-methylsulfonylbenzoic acid was prepared from 4-toluene sulfonyl chloride by the reaction of Alkylation (in the condition of sodium sulfite and baking soda), Nitrification (in the condition of nitric acid and vitriol) and Oxidation reaction (in the condition of nitric acid and catalyzer).

研究了以对甲苯磺酰氯为起始原料，首先通过亚硫酸钠和碳酸氢钠的水溶液进行烷基化、其次在浓硝酸和浓硫酸加热回流的条件下峭化、最后在浓硝酸和催化剂的条件下进行氧化，3步反应合成了玉米田高效除草剂甲基磺草酮的重要中间体2-硝基－4-甲磺酰基苯甲酸。

Stable nitritation is realized because the nitrobacter is sensitive to the changing environment. When the dissolved oxygen and pH values in SBRⅠ and SBRⅡ are 2. 4-3. 0mg/L, 7. 0-8. 5, 1. 5-2. 0mg/L and 7. 0-8. 5 respectively, a lot of nitrate isn't found during operation in two months, and nitrosation rate is over 80% in two aerobic reactors.

将SBRⅠ、SBRⅡ好氧反应器的溶解氧、pH分别控制在7.0-8.5、2.4-3.0mg／L及7.0-8.5、1.5-2.0mg／L时，依赖SBR反应器水质波动大、硝酸菌对环境变化敏感的特点，在较高浓度NH〓-N条件下，实现了稳定的亚硝化反应，系统运行近两个月，没有大量硝酸盐的积累，两个好氧反应器的亚硝化率均在80％以上。

Nitrobacter can gradually acclimate to nitrous nitrifying conditions and refreshed, so the sludge should acclimation and the nitrite accumulation disappear.

3低浓度氨氮废水亚硝化系统稳定运行一段时间之后，硝酸菌能逐渐适应亚硝化条件，恢复活性，从而使污泥产生适应性，亚硝化现象消失。

Methods: 2ethyl aniline was used as starting material of the synthesis and was processed by acetic anhydride acylation, strong nitric acid nitraction at low temperature, and desacyl synthesis to produce 2ethyl5nitro aniline. The product was then synthesized to 3methyl6nitro1Hindazole by using ringclosing reaction in the presence of NaNO2, and then ethylated to obtain 2,3diethyl6 nitro2Hindazole. The latter compound was then reduced by SnCl2/Hcl to get target compound 2,3diethyl6nitro2Hindazole.

以2乙基苯胺为原料经醋酐酰化、浓硝酸低温硝化及去酰基保护合成2乙基5硝基苯胺，后用亚硝酸钠关环得3甲基6硝基1H吲唑，经硫酸二甲酯甲基化得2，3二甲基6硝基2H吲唑，最后用氯化亚锡将其还原得到目标产物，通过1H NMR确定结构与目标产物一致。

Methods: 2-ethyl aniline was used as starting material of the synthesis and was processed by acetic anhydride acylation, strong nitric acid nitraction at low temperature, and desacyl synthesis to produce 2-ethyl-5-nitro aniline. The product was then synthesized to 3-methyl-6-nitro-lH-indazole by using ring-closing reaction in the presence of NaNO2, and then ethylated to obtain 2, 3-diethyl-6- nitro-2H-indazole. The latter compound was then reduced by SnC12/Hcl to get target compound 2, 3-diethyl-6-nitro-2H-indazole.

以2-乙基苯胺为原料经醋酐酰化、浓硝酸低温硝化及去酰基保护合成2-乙基－5-硝基苯胺，后用亚硝酸钠关环得3-甲基－6-硝基－1H-吲唑，经硫酸二甲酯甲基化得2，3-二甲基－6-硝基－2H-吲唑，最后用氯化亚锡将其还原得到目标产物，通过1HNMR确定结构与目标产物一致。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。